Anyone here working on any interesting building projects?

[Neven]

Jim, thanks a lot for the suggestions, I really appreciate it. At the same time I want to do more than just build things the conventional way, as it generally annoys me quite a bit (without throwing out the baby with the bathwater, of course).

I'm not into tiles because they take too much energy to make and you still have to take measures to make sure a leak isn't immediately disastrous. Oh yeah, and the bloody silicone sealants that don't work.

I'm not into water-resistant paints that require respirators either.

I know EPDM isn't the holy grail of sustainability, but it's pretty eco-friendly and doesn't take that much energy to produce. It's extremely sturdy and can withstand most substances, except for oils. Right now - with the criteria of sustainability, level of DIY and cost in mind - I can't think of a better material than EPDM to line the walls of the U-shaped shower. I thought about gluing the EPDM to the shower tray, but I don't like glue much either. I will put more thought into the connection part between EPDM and shower tray. But I'm also going to test the clamp idea on a smaller scale. It doesn't necessarily need to be clamps. I could also just screw boards together, and make it very tightly fixed, although I like to be able to take things apart again easily (hence the clamps).

Two further important points:

1) My wife and I are willing to take risks and experiment (up to a certain point, and if it doesn't compromise the entire house). If I were to build this EPDM shower cabin, I would build it in such a way that it can easily be fixed or replaced. I know that if I'm going to build the bathroom in a conventional way, I'm going to regret it later.
2) My family is pretty unconventional. For us a shower is all about function, rather than comfort or aesthetics. I shower every other day very quickly. My wife and daughter only shower twice a week. At the same time, you're right that the shower must not look scummy. Otherwise I would just built some hippie shower like this:



 

You said your wife was a warranty manager for large scale home builders. I know from experience that these contractors fear nothing more than reclamations. This is why they oversize everything, just to make 200% sure that nothing can happen. From a business POV this makes sense, not from an eco-sustainability POV.

In this case it's about just some European schmuck who is willing to take the responsibility for his own f***-ups, on the off chance that something might work and be more sustainable. So, forgetting about warranty and that kind of stuff, is there anything out-of-the-box that your wife might have seen during her career that didn't seem too crazy? You know, I can always tile the shower and bathroom in 4-5 years, if things aren't working.

Sorry for being so stubborn! I like doing extreme eco-stuff that hasn't been tried or done before (like building wooden low-power computers) without going all-out back-to-medieval-times. 

[sidd]

Re:EDPM

Gluing it correctly is impotrant. I have put it in in some places, and overlapping like shingles at the joins helps. But if you dont get EDPM that incorporates fungicide, and it is exposed to both air and water, it will grow a green coating, or a multicolored coating of small live things. I can see this on EDPM that was originally covered by fill in a water diversion project down the road, the guy that owned the property was giving me chapter and verse. I dunno if the fungicide/EDPM product meets code for indoor residential install, i do know that such a construct in a shower would not meet code in most USA/Canada residential zoning jurisdiction. Of course, if you are zoned agricultural, hey, do what you please, nobody will bother you. Except mebbe the fungus. Or the fungicide on bare skin. I shall try to find out what they use to retard fungus, but i fear it will turn out to be poisonous.


sidd

[JimD]

Neven

Not to worry as I am just tossing out info.

If you are going to pursue very unusual alternatives then it does behoove you to rethink the osb in the bathroom.  High humidity and condensation, not to mention potential leaks from unusual construction techniques kind of argue strongly against the osb.  Cement board is very durable and can save a lot of rot and extra expense in having to tear walls down to the framing to replace rotted osb.  Under the best of conditions osb  does not have a real long life span if exposed to a lot of moisture compared to many other materials so one does need to be careful with using it.  But as always this is just info for you to think about. 

An alternate idea  for the shower is to eliminate the shower pan normally used and install a wooden slat floor which the water passes right thru.  Design the floor to be able to pull it up for maintenance (so you need some kind of non-corrosive frame for it to sit on that is attached to the water pan described below).  Run your EPDM sheets below the wood floor about 6-8 inches and then fold them back upwards about 6 inches before you clamp and have your clamping arrangement be at a slight uphill angle away from the shower so moisture can only wick up there and not flow up there.  The folded bottom of the EPDM hangs down into a metal sealed seam non-corrosive pan which has walls that rise up to the clamp location.  The pan directs the water into a drain hole and on to your water catchment system.   (you would need to use a wood which can handle being wet frequently such as teak or the kind of wood used in steam sauna's or the manufactured deck wood (Trex is one brand).  This arrangement would keep the water away from the clamped location and also ensure that water does not pool or splash on the clamped location.  And you can grab the floor lift it out and easily clean any crud off any surfaces and also inspect your installation occasionally. 

[Neven]

Re:EDPM

Gluing it correctly is impotrant. I have put it in in some places, and overlapping like shingles at the joins helps. But if you dont get EDPM that incorporates fungicide, and it is exposed to both air and water, it will grow a green coating, or a multicolored coating of small live things.

Now that would be a show stopper!

I would think that as long as it has enough time to dry out, there won't be a problem. But perhaps not. Darn it. I'll have to look into this.

Neven

Not to worry as I am just tossing out info.

If you are going to pursue very unusual alternatives then it does behoove you to rethink the osb in the bathroom.  High humidity and condensation, not to mention potential leaks from unusual construction techniques kind of argue strongly against the osb.  Cement board is very durable and can save a lot of rot and extra expense in having to tear walls down to the framing to replace rotted osb.  Under the best of conditions osb  does not have a real long life span if exposed to a lot of moisture compared to many other materials so one does need to be careful with using it.  But as always this is just info for you to think about. 

You're absolutely right. If I'll use OSB for building a stall, I will make sure it doesn't get in contact with moisture.

An alternate idea  for the shower is to eliminate the shower pan normally used and install a wooden slat floor which the water passes right thru.  Design the floor to be able to pull it up for maintenance (so you need some kind of non-corrosive frame for it to sit on that is attached to the water pan described below).  Run your EPDM sheets below the wood floor about 6-8 inches and then fold them back upwards about 6 inches before you clamp and have your clamping arrangement be at a slight uphill angle away from the shower so moisture can only wick up there and not flow up there.  The folded bottom of the EPDM hangs down into a metal sealed seam non-corrosive pan which has walls that rise up to the clamp location.  The pan directs the water into a drain hole and on to your water catchment system.   (you would need to use a wood which can handle being wet frequently such as teak or the kind of wood used in steam sauna's or the manufactured deck wood (Trex is one brand).  This arrangement would keep the water away from the clamped location and also ensure that water does not pool or splash on the clamped location.  And you can grab the floor lift it out and easily clean any crud off any surfaces and also inspect your installation occasionally. 

These are some very interesting suggestions. Thanks.

I need to think about this some more and do a couple of extra rounds of Google, before proceeding. There is still time...


[/quote]

[skanky]

Hi Neven,

I remember using tile-less walk in showers in some hot countries in the distant past (eg Mexico) but don't know what they used instead (I was some sort of treated render). I tried to look it up but found this instead:

https://designnsuch.wordpress.com/2011/02/13/alternative-to-stone-and-tile-in-the-shower/

Also this with the early discussion of the pasters:
http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=3297

The shower panels they talk about come from many manufacturers, here's a couple of examples:
http://www.bathroommarquee.co.uk/
https://www.wetwall.com/

Re the sealant, I have seen someone use an extrusion (I think the term is) frame over the top of the sealant (the base is embedded in it). While it doesn't remove the need, it tends to keep it dry, so it doesn't develop mould and need replacing.

Finally, if you are still going down the EPDM route, you can get EPDM tiles that are designed for children's play areas. They could make a durable, soft and non-slip base.

Just a few ideas - I doubt any are completely new.

[Neven]

Thanks a lot for sharing this, skanky.

Hi Neven,

I remember using tile-less walk in showers in some hot countries in the distant past (eg Mexico) but don't know what they used instead (I was some sort of treated render).

Somehow it's difficult to find much info on this (tadelakt was mentioned earlier), at least if you want to do it without all the plastic stuff.

A couple of days ago I found one picture of a back-to-the-land-style shower that I forgot to share here. Some kind of plaster full of black stains (probably mold).

Somehow I think that a render/plaster/stucco will turn problematic over time, but it's useful at joints and corners.

I tried to look it up but found this instead:

https://designnsuch.wordpress.com/2011/02/13/alternative-to-stone-and-tile-in-the-shower/

Looks nice, but this turned me off:

The shower process went like this…
Install water resistant durock (it’s purple) to form walls of shower.
A cementitious waterproofing system called Acryl Thoroseal was applied on top of the durock and all joints were taped with a special membrane tape.
Then the Deco-Poz was applied. We are now going to seal that with a two part Epoxy sealer from V-SEAL called StoneLok E3 used in tandem with StoneLok E2.

The shower pan is a rubberized shower pan and concrete was applied over that to create the slope of the shower floor. It was then finished with the Deco-Poz.

Reduce, reuse, recycle? 

Also this with the early discussion of the pasters:
http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=3297

That's an interesting forum, thanks.

The shower panels they talk about come from many manufacturers, here's a couple of examples:
http://www.bathroommarquee.co.uk/
https://www.wetwall.com/

Panels are interesting, but still need sealants at joints and corners. That Wetwall site made me chuckle a bit. First they have this:

Our panels are constructed by bonding High Pressure Laminate (HPL) to a Medite MR MDF core using a PVA (D4 rate) adhesive system to give a completely waterproof surface. This meets all the requirements of EN438. A balancing laminate is bonded to the reverse of the panel also using the PVA adhesive system.

Followed by:

Ecological

Laminated panels feel much warmer than tiles and have a significantly lower u value (Thermal insulation) 3.4 typically compared to 5.9 (tiles). This means that Wetwall helps to keep your bathroom or shower room cosy - our panels lose less heat and are therefore more efficient. Also because our panels are guaranteed for 10 years, which is significantly greater than alternative materials, this reduces their need to be replaced as frequently hence the obvious environmental effect.

Pretty smart. They probably know that a percentage of potential customers are a bit like me. All in all it doesn't sound very eco, but I'm not an expert. And like I said, it's not like EPDM and an acrylic shower pan are panacae. If they were, I'd start a company called Shower Panacea. 

That Bathroom Marquee website had a very nice no-nonsense pre-fab alcove shower cabin though:



Not so cheap.   

I've looked a bit into EPDM and mildew, but apart from a lot of info on how to keep your rubber RV roof clean, couldn't find that much. Except that a squeegee (a word I had never heard or read before) would be useful in wiping the EPDM so that it dries out quicker.

[skanky]

We use a squeegee on the tiles in our very standard UK bathroom, to reduce mould, so it's not overly arduous. 

I think you're basically going to have to make an ecological compromise one way or another with a bathroom in cold climates. There are trade-offs though and you might find that the best you can do is go for the longest lasting stuff. Finding the right expert is perhaps the best approach?

Good luck anyhow. Wish I'd looked into this before I bought my house years back.

[ccgwebmaster]

I think you're basically going to have to make an ecological compromise one way or another with a bathroom in cold climates. There are trade-offs though and you might find that the best you can do is go for the longest lasting stuff. Finding the right expert is perhaps the best approach?

Given the energy and resource inputs of manufacturing involved in even more environmentally friendly options, I'd tend to agree longevity might be the most environmentally friendly choice - even if the materials and processes used to make it aren't quite so much?

I don't even have a shower as being discussed per se yet though, so I can't really comment 

http://www.duckworksbbs.com/gear/shower/index.htm

[Neven]

I think you're basically going to have to make an ecological compromise one way or another with a bathroom in cold climates. There are trade-offs though and you might find that the best you can do is go for the longest lasting stuff. Finding the right expert is perhaps the best approach?

Given the energy and resource inputs of manufacturing involved in even more environmentally friendly options, I'd tend to agree longevity might be the most environmentally friendly choice - even if the materials and processes used to make it aren't quite so much?

I agree, and that's why I'm thinking of EPDM. Take this for instance (found here):

What material can support a vehicle going 120 mph through a steaming desert and still be flexible at -45 degrees C. (-49 degrees F.)? For roofing applications, materials must also have a high degree of weatherability – especially resistance to water, pollutants, UV rays, and impact and general traffic resistance.

Materials that meet these requirements are called elastomers. ASTM D-1079 defines an elastomer as “a macromolecular material that returns rapidly to its approximate initial dimensions and shape after substantial deformation by a weak stress and subsequent release of that stress.”

EPDM has advantages over other elastomers in that its weathering resistance is extraordinary and its raw materials are highly cost effective.

(...)

LEED
EPDM has proven to be extremely durable and maintainable. Warranties have recently been increased to 30 years in many cases; with proper maintenance, life can be extended even longer. Single-ply membranes are thinner than BUR and modified bituminous membranes (45 to 90 mils compared to one-quarter inch or more) so, at the ultimate end of life, there is less volume headed to the landfills. The ballast is recyclable, whereas roofing gravel is embedded in asphalt and can’t be reused (except with great difficulty). From a transportation point of view, ballast and pavers can be produced locally while shipping of large EPDM rolls from the few U.S. factories is not overly burdensome. There has been some success in recycling the rubber membranes, with more than 5 million square feet of membrane recycled in the past 3 years. So far, recyclers will only accept un-adhered membrane – the adhesives and attached insulation facers are too difficult to process.


I found this graph in this PDF on EPDM life cycle analysis:



The production process is dependent on oil (byproducts), though.

[ccgwebmaster]

The production process is dependent on oil (byproducts), though.

Using oil for manufacturing things - materials and chemicals - is arguably substantially better than using it simply to burn. Of course avoiding it's use in manufacture is desirable, but some materials and pharmaceuticals I think cases can be made pending organic alternatives (possibly the organic waste to oil processes could yield suitable feedstock - not sure offhand).

I'm curious though - the above figures - how are they calculating global warming potential? Is that the carbon embedded in the product (which is necessarily bound up for a long time, albeit not perhaps as long as the oil before it was pumped from the ground), or does it include a big hit for manufacturing processes etc on the assumption they are fossil powered?

You've inspired me to look up the figures for steel (my boat being steel) and apparently the new steel I've added likely makes me responsible for several tonnes of carbon dioxide. If one included the rest of the vessel in my footprint (as though I had built it all rather than bought the hull) it would need to last rather a long time to give an acceptable figure (and of course making it last entails painting and maintenance all of which consume energy and materials based on oil).

How do you think your total emission figures will stack up for your house in the end? How does that play out over the expected lifespan of the structure? (mild steel is capable of being maintained and repaired almost indefinitely if you keep on top of things - but the keeping on top of it is critical).

[sidd]

Over many centuries tile/concrete has been used because it is better than alternates. One way to reduce fossil use is scavenging. Last bathroom i put in was entirely built with tiles and concrete board scavenged from other construction and demolition projects. So much left, that next bathroom on the list is covered. (I have plenty of storage space, these are farm properties.)

If you play your cards right, they will pay you to haul the (usable debris/leftover) from demolition or new build sites. The fossil burden is already incurred, you add nothing by repurpose, and save landfill volume. Downside is that i still get fonecalls from contractors who would love me to haul more such (to them) junk away, since their waste haulage/landfill tipping fees are exploding. If you have access to, say, a triaxle hauler, you may never need to buy construction material again.

Good luck, let us know how it turns out.

sidd

[Neven]

How do you think your total emission figures will stack up for your house in the end?

I want to calculate this when we're done. I think we did OK. We used as little concrete as possible, by putting the house on concrete pillars instead of a slab (I think I posted pictures at the start of the thread). More than 90% of total materials is wood and cellulose (recycled paper). A lot of the materials have been sourced regionally. We're buying as much second hand stuff as we can.

And if everything turns near to what I expect/hope, we should be needing very little energy. Relatively speaking, that is. My estimation is about 4000 kWh per year for a family of 3, and that includes hot water and heating. Our solar panel array will produce around 6000 kWh per year. Oh, and we stole this plot back from a corn field. We're planning to grow around 10 trees and lots of plants.

Either way, it's much better emission-wise than a brick and concrete home, but how much better, I don't know yet.

What's disappointing, is that there's a young lad we know, who comes around every now and then to pick up ideas for the house he plans to build this year. He's quite eco-conscious, but still adamant about building a brick house. It depresses me a bit, because I'm also building this house to show others what can be done. But everyone builds brick houses, here in Austria. It's so ingrained in the mentality (from the 50's-90's) , although there's a fantastic wood working tradition here.

How does that play out over the expected lifespan of the structure? (mild steel is capable of being maintained and repaired almost indefinitely if you keep on top of things - but the keeping on top of it is critical).

When keeping on top, the lifespan should be more than 80 years. But that's my guess, could be much more, especially as we're building in such a way that everything can be replaced. Some luck is needed though. There might be big construction mistakes or and accident.

Over many centuries tile/concrete has been used because it is better than alternates. One way to reduce fossil use is scavenging. Last bathroom i put in was entirely built with tiles and concrete board scavenged from other construction and demolition projects. So much left, that next bathroom on the list is covered. (I have plenty of storage space, these are farm properties.)

If you play your cards right, they will pay you to haul the (usable debris/leftover) from demolition or new build sites. The fossil burden is already incurred, you add nothing by repurpose, and save landfill volume. Downside is that i still get fonecalls from contractors who would love me to haul more such (to them) junk away, since their waste haulage/landfill tipping fees are exploding. If you have access to, say, a triaxle hauler, you may never need to buy construction material again.

Good luck, let us know how it turns out.

sidd

Thanks, sidd. I will.

My favourite place is the local garbage dump. It's mindboggling to see what people throw away! I often take my daughter with me who finds stuff she likes there, so we don't have to buy toys. When she's done, we bring it back again.

A couple of weeks ago the guys working there approached me (slightly aggressively) to tell me that scavenging was now against the law. I understood their problem: 1) people coming from Hungary to sell the Austrian garbage back home, and 2) potential accusations of them doing business on the side. But still I tried to make clear that I was a local, and that it was a shame to let those things go to waste. They even have big signs promoting stufff like 'reduce, re-use, recycle'!

One argument was so silly. The guy told me that they got complaints from people who were actually annoyed that their stuff was re-used, rather than destroyed. Austrians are like that with their stuff (not all of them, of course). So I asked if I could take the non-personal stuff, like bricks and wood and metal scraps. No, I couldn't.

In the end the guy said: "OK, I'll let you take that table, but it's the last time!" To which I replied: "OK, I'll pay you later!". Unfortunately, Austrians don't get my sense of humour yet. 

But I'm going to have to talk to the boss, or even the mayor. I need my garbage dump. Where else can I scavenge? I'm so not ashamed about that! 

[ccgwebmaster]

One argument was so silly. The guy told me that they got complaints from people who were actually annoyed that their stuff was re-used, rather than destroyed. Austrians are like that with their stuff (not all of them, of course). So I asked if I could take the non-personal stuff, like bricks and wood and metal scraps. No, I couldn't.

This is all too common, and I think a sad reflection of the modern mentality of wealth and entitlement where someone feels they paid for the item and therefore nobody else should use it even after they have finished with it as obviously they should go out and work and buy another. One of the worst forms of petty envy, surely (usually it is directed at someone of lesser means - I generally find poorer people much faster to share or pass on things that still have value left as they understand the benefits of cooperation here better).

I've used quite a considerable number of pieces of "scrap" or "someones trash" myself for my vessel quite happily. Too broke to do otherwise and most of that stuff has a minimum of many years of good service left in it.

[sidd]

Don't need  to go so far down the chain as landfill or dump site. Look at the local ads in the paper, see who the construction guys are, offer to come in an haul away whatever you can use. They are paying for every cubic yard of waste they got to have hauled and tipped, you gonna save em money.

Incidentally, incredible tool for concrete board and tile scavenging, just came out a couple years ago, look at "Rotozip" .

The bits cost, US$80 or so, and (gotto wear breathing protection for concrete board, and of course, eye shield all the time), but it is a pretty thing to see it going thru tile and masonry. closest thing i seen to freehand. Beats the hell outta screwing with grinders or tilesaw for small work. Of course, tile is an art, if you design and execute right there is very little small work. (I'm not nearly that good.) But checkout rotozip, if you scavenge tile, or for that matter concrete board.

sidd

[bligh8]

 

I'm not sure if wood would work. I have a friend who makes furniture and we discussed making a shower cabin out of larch, but I think it would look less and less welcoming very quickly. And I'm not sure about how water-proof it is, especially at the seams (which are always the problem areas in construction). Oh, and it would be mucho expensive
[/quote]

Neven
This customer had a ongoing and continuous mold/moister problem.
I’ve done this to several bathroom ceilings where power ventilation was not economically feasible. The wood is Knotty Pine tongue and grove, 5/16thx6in,
Pin nailed through the tongue to the rafters. The entire job is inexpensive, attractive (depending on one’s taste). It works well for moister control as the wood absorbs excess moister and over time releases it. I coated this ceiling with a hand rubbed thin coat of Shellac; this ceiling is 4 yrs old.  I would not use wood where there was direct water contact.

[idunno]

I have it on several good authorities that the best wood to use anywhere damp is chestnut. It never rots.

I am tired. Solar thermal, Neven. Solar thermal. Scavenge some old radiators, paint 'em black, enclose in insulated boxes, under old scavenged windows, litter these around your roof; and when you've worked out how to stop them boiling and exploding, you could always use these pages to post up some advice that is so simple that even tired people can follow it.

Seriously, solar thermal works; so damned well that there is nobody making enough profit installing it to make it worthwhile to publicise it via the interthingy. Solar thermal is just better than;

1. Photovoltaic

2. Microwind

3. Tidal

4. Macrowind offshore or on

5. Conventional nuclear

etc, etc...

47. Coal

Unless you're holding out for micro-thorium, solar thermal. You need a clever plumber.

[bligh8]

Id
Trust me, all wood rots…except teak. Your, however correct in that chestnut is a higher density wood, and would be less likely to rot than say pine. In a low moister environment like a bath, the 5/16in. pine has worked fine for years, without mold or degradation. The down side of chestnut is expense where pine is relatively cheap. I posted this, as an alternative to power ventilation, but none of this may be necessary, if I remember correctly there’s a window in the room in question.

I like your idea of solar thermal…sounds as if it would work. Providing the structural integrity of the roof was designed for that kind of weight. Standard 2x6 framing rafters on 18in centers are not designed for load bearing items. Commercial grade buildings where heat/a/c units are on the roof there’s 2/12 box framing over a load-bearing wall, supporting these items.

Best,
Bligh

[Neven]

Solar thermal is just better than;

1. Photovoltaic

Personally, I'm not sure of that, idunno. Solar thermal always was a no-brainer for me, as it's cheap and everything. But then, when I started investigating, it occurred to me that you need quite a bit of material, there's quite a bit of plumbing, there's a pump that uses electricity. And then when someone told me about his problems with solar thermal (and this is a smart and very handy guy), about leakage because things would get just too hot in summer. Way too much hot water in summer, barely anything in winter (meaning you need a second system to heat your water).

I agree, it used to be true that solar thermal was the way to go, but PV has overtaken now. It's smaller, simpler (relatively, still need an inverter), lasts longer, and combined with a good heat pump, very hard to beat when it comes to energy efficiency. Besides, electricity is much more versatile than heat, and can always be used for something. Add some batteries (modern ones, not lead acid) and things really start to get interesting.

PV shares solar thermal's winter problem though. I'm starting with a PV array and a high-quality heat pump, and then want to see how that works for a year or two. If needed, I will add a water-heating wood oven (80% water - 20% air) for those couple of winter weeks where electricity isn't enough. I hope that in a year or 2, 3 something really interesting gets developed for storage.

In my case solar thermal wasn't the best option.

As for your other points:

2. Microwind

3. Tidal

4. Macrowind offshore or on

5. Conventional nuclear

etc, etc...

47. Coal

I'm not a fan of either of these energy sources, and also would pick take solar thermal. Energy efficiency and practical minimalism are the best energy sources.

[idunno]

Hi Neven,

thanks for your typically thoughtful response to my typically thoughtless post (forgot you'd aready picked option 1)

please read above as me writing a memo to self; its one of the next tasks on my list. I hope to collect rainwater into a header tank, with a stopcock, and have the whole fandango gravity-powered and not pressurised; thus avoiding explosions.

meanwhile, all this cultiver le jardin has me done up, mais il faut...

[TerryM]

Idunno
Watch out for anything but copper tubing to connect your system. Any of the plastics, (PVC or ABS) expand enormously with temperature change and will pull themselves apart. A tight loop of soft drawn copper allows expansion and can keep everything dry (thats supposed to be dry).
Good lock with your build & keep us informed.
Terry

[ghoti]

I have both solar PV and solar domestic hot water. In North America solar domestic hot water is as expensive to install as PV now.

In Canada solar hot water cannot supply enough hot water during the winter because of a combination of short days and rather cold temperature of input water. This is even the case with a system with angles optimized for winter and sized too large for summer (have to dissipate excess heat) with a 300 liter storage tank. So back up heating is required.

In general people also use more electrical energy than hot water energy so the electrical energy generated by PV is likely a more important offset. Like solar hot water winter generation of PV electricity is very low for several months a year but huge excesses in generation (relative to my consumption) are provided to the grid for my neighbours to use.

Despite my solar hot water not being as cost efficient as my PV it results in more CO₂ reduction since hot water is otherwise heated by a high efficiency natural gas heater and electricity here is over 50% nuke and maybe 25% hydro and 0 coal generated. As such the best part of my roof is used by the hot water system.

If you are going for a homemade solar water system you can likely do it for less than solar PV but building code requirements here make the whole design/installation/inspection process quite expensive. If those don't constrain you I'd suggest you look into the very inexpensive and simple systems used for heating swimming pools. They aren't usable in the winter but in my opinion the winter can be considered a write off. Overall annual gain is probably increased if the system is focused on the non-winter months anyway.

I'm not positive home made solar water would be significantly less than PV as well. The vast majority of the cost of PV now is installation and meeting code and local electricity requirements. If you purchase and install PV yourself in an environment without high soft costs it is a bargain relative to the return.

[Neven]

Good points, ghoti.

Let me re-stress: Until not too long ago solar thermal was the way to go here in Europe (Germany and Austria), and probably still is in other places, depending on the area. I think PV combined with a heat pump for warm water is the way to go for our situation, because it's just as cheap in the long run and (relatively) simpler.

They're both good.

[SATire]

I think PV combined with a heat pump for warm water is the way to go for our situation

I concur to that. The only more efficient combination is wind and heat pump. But for that you need 99 neighbours needing such a solution at the same time. So practically PV is the way to go for individuals.

[ghoti]

I love heat pumps. Technically I still have one but it is air to air and by today's standards very inefficient. Now mine can only be used as an air conditioner but it hasn't been powered up since the major power outage of 2003 that struck many millions of people in North America.

I've considered a ground sourced heat pump but they cost scandalously huge amounts of money. They don't make any sense here if you don't air condition your house. There isn't a good reason for their very high price other than the money they save - the price isn't based on the cost of manufacture and installation.

Since you own a field next to your house you probably could install a ground loop for a less outrageous price than us city folk. I venture to say if you want it for heating water a heat pump is much more costly than any other method including the fanciest Solar domestic hot water system.

[Neven]

I venture to say if you want it for heating water a heat pump is much more costly than any other method including the fanciest Solar domestic hot water system.

Perhaps this is true. I must say that I haven't calculated very precisely. Basically my calculation boiled down to this: Solar thermal costs about 3500 Euros over here (subsidy subtracted). Heat pumps for heating water and air are very expensive, although relatively cheaper than oil or gas heaters. But as our house has pretty good insulation values, we decided to go for just water heating. The air-water heat pump (300 l/75 gallon tank) we ordered is Austrian-made, very efficient, high quality, and costs around 2250 Euros. We could've taken a Chinese version, which would've cost about 500-750 Euros less, but I try not to do that, if I can. There are additional costs for the PV solar array (costs: approx. 7500 Euros), of course, but it's difficult to say how much of that would need to go to the heat pump.

Although solar thermal modules would've fitted on our roof, it gets a bit crowded with the PV. I also wasn't thrilled about all the piping involved, having to go through the roof twice (thermal bridge), and then from the front of the house to the back of the house (albeit under the roof, not downstairs). The system we have now is much simpler, and easier for me to visualize, which is good, as I want to be in control and do a lot myself. One other minor advantage: the heat pump cools the air in the attic in Summer.

So, again, I think this was the best option for us. But we'll have to see how things work out in practice.

[Neven]

The other two options I investigated:

1) Just simple electric boilers (one for each bath room) with 100-150 l capacity (25-40 gallons), but the heat pump is 4 times more efficient. I get a kick out of efficiency, and I also have less of a problem during winter, when PV will at times not be enough to heat water.

2) Tankless heaters are the most efficient way of heating water, in the sense that you don't have any losses and water can't calcify. You also need very a lot less material than for other options, and no additional plumbing required. BUT, these babies need at least 10 kilowatts to do their thing. That amount of energy cannot be supplied by my 5.25 kWp PV solar array under the best circumstances (5000 W is the max, maybe a bit more), let alone during winter. That was the deal breaker for me, although this was my first option for quite a while.

And so we opted for the heat pump. If our house were less well-insulated, solar thermal + wood oven (50% water, 50% air), might have been the best way to go.

[ghoti]

I hadn't even considered an air to water heat pump just for heating water. I don't think they even exist here. The cost you list is the same or lower than tankless natural gas systems sold here (though rarely because of the high cost) and certainly sounds preferable.

Your winter temperatures are clearly much warmer than ours. Many winter nights with sub -20C temperatures here make air source heat pumps rather less efficient than they otherwise might be.

[Lucas Durand]

Hi Neven,
Not to confuse your plans but I had a few thoughts while catching up with some of this discussion.

With respect to solar thermal heating...
I will be installing a solar thermal system on my own house - despite the fact that this is now considered to make very little sense in a market now dominated by cheap PV and increased availability of heat pumps.
The reason I choose to do so is that a solar thermal system contributes a lot of resilience by virtue of being very simple and reliable (possibly more "maintainable" than a more complicated PV/heat pump combination) - especially when using flat-plate collectors, ground mounted in a closed-loop system using a DC pump directly wired to a small PV module.
In my climate, I will almost certainly not get all the bulk hot water I want from solar thermal, but I know that if the grid is down I should always have at least some bulk hot water for occasional use.
If you are adventurous you can always experiment with thermosyphon heat exchangers between a wood burning appliance and the water tank to make up the extra heat missing on cloudy/short days (these can be done quite well but a constant eye towards safety is very important).

[Neven]

You're right, Lucas, and I should've mentioned it: PV is more complex than Solar thermal (although I probably couldn't do much with the latter either). I was surprised at how big my inverter was. Solar thermal is better if you want to be even more independent.

I'm experimenting a bit with loam and wood shavings to fill the interior walls, as I can't get the hemp insulation boards I wanted, and frankly, it's too costly at this point. I'll report if things work out (with emphasis on work ;-) ).

[Tor Bejnar]

I've not been following your homebuilding project hardly at all, but you are smart to get so much input from others. 

I built a ~1 KwHr/day solar-electric (off grid) reused timber-framed house in New Hampshire, USA in the 1980's.  Wanting simple systems, I heated the house and DHW (domestic hot water) with a wood cook stove (Amish designed stainless steel construction - loved it).  For summer DHW, I put a 5 gallon tank in a black box with a single pane of glass over it to pre-heat water for a traditional (free-used-old) propane DHW tank that didn't come on very often.  Although I had an inverter, I also used 24 volt DC lighting where I most needed it.  (Today, of course, PVs are much cheaper and better!)  I did keep two 55 gallon barrels in the attic for when my water pump wouldn't work (low batteries wouldn't provide enough juice to start the pump 200' down the well)- the water siphoned into the home's system when the valve was opened.

I loved raising my daughters in an environment where they could connect life's chores (like fetching firewood from the wood shed) with life (it's cold without heat). 

When I moved to Florida, I gained weight (no more shoveling/plowing the 0.8 km driveway [or walking it when it closed due to ice buildup and then mud season] or cutting/splitting wood) and I'm back to earning money to pay for mains electricity and a switch on the wall that kicks in the AC (ground sourced heat pump).  My persistent winter cough went away though: breathing some smoke, it seems, was worse for me than our intense pollen season.

A neighbor family had their shower stall lined with cedar shingles; I presume it grew moss if they didn't use chemical cleaners.  (I installed a "seconds" fiberglass shower stall.)

[JimD]

Neven

You have competition!

This couple built their own tiny home for $10,000

http://finance.yahoo.com/news/this-couple-built-their-own-tiny-home-for-less-than--10-000-162920658.html

[yan]

Hi Neven

I discover your "excellentissimo" Sea Ice Blog a few mouths ago but just today the forum on "ecological house" and "gardening".

Following 2 images:
- my solar house that y build in 2010

- the garden designed with the principes of Permaculture

I live in South France near Aix-en-Provence. The house is larger enouth for 2 familys, it's a kind of "little community house", we share electricity sources and hot water. Each family need less than 25 kWh / m2 / year for heating+cooling+electricity.  My family is at the floor. The garden in Permaculture is very resilient when we have high temperature , ex. 38°C for several days in summer.

If you or anyone have any questions on solar house or ecological gardens I will be happy to describe my experiences on this topics. (excuse my limited english)

[Laurent]

Hello Yan,

That's an interesting experience. Don't you have a website ? If you want to show us your experience with your garden in the garden thread...thanks in advance.

[Neven]

Seconded. I'd like to hear more about high temperatures and your mulching techniques.

Very nice house, Yan! How do you heat and cool, and how many kWp is there mounted on the roof? 25 kWh per m2 is very sharp. Well done.

I've been doing some stuff (filling inner walls with loam and wood shavings) that I'll share some images of soon.

[yan]

Neven and laurent I will be happy if I can help 

Neven, we have 22,6 kWp of solar pv on the roof. The solar generator produce 20 times (!!) the need for the 2 familys so we resale electricity to the national operator (price 60 cent / kWh). Electricity consumption for the 2 familys: 1600 kWh / year.
Monitoring pv production since 2010: http://www.bdpv.fr/fiche_utilisateur.php?util=yan13

The house is solar passiv so during the winter solar is enough for about 60% of heating need. For additional heating each family has a little wood furnace of 4 kW. For the entire cold season each family burne 2 m3 of local pinwood (we cut it before buiding the house because we are in the forest). During the hot days of summer we need...nothing to cold the house  . Bulkhead inside the house are made of heavy compressed mud brick which accumluate the fresh during the night  (we just need ventilation and we open windows) and restitute it during the day. Compressed bricks have a interesting capacity of "thermal phase displacement" during 12hours and it works both for the refresh in summer and heating in winter.
About the house and its construction: http://habitat-et-environnement.net/
(sorry only french) but you have numeros photos and videos in the subnail "Galeries photo et video" 


Garden in Permaculture.
The main advantage for us with Permaculture approch is to reduce water consomption. We estimate that we can divide by 2 or 3 the need for water compare to a traditionnal garden with no protection of the soil. Secondly we need no chemical treatments, we appreciate organic food. And of course we respect natural process of soil, animals (worms) and plants.
I founded a non-profit association in my village (20 km north of Aix en Provence) to learn, share and develop experiences in Permaculture with the other inhabitants of the village.
On the website you will see plenty of photos of Permaculture: http://jardiniersdepeyrolles.over-blog.com/
Slideshow "how to build a mound of soil" with Permaculture:
http://www.e-quilibres.net/espaces/paysdaixentransition/index.php?Esp=8&p=../inc/inc_description_article.php&Id=199


I'm a local member of "Transition Network", a worlwide movement founded by Rob Hopkins. Anyone have been hearing about ?

[Laurent]

Thank you,

We know hopkins of course. We had a discussion recently with the recent call of David Holmgren for an economic crash and the answer of hopkins.
http://forum.arctic-sea-ice.net/index.php/topic,723.0.html

Do you plan to have small trees in your garden ?

[Neven]

Oh wow, I have only read and not looked at any images yet, but I love your house, Yan! Fantastic work. A house of the future.

But 1600 kWh/yr for two families?! That's amazing. I believe pets in the US already consume that amount of electricity. 

Do both families live there all year round? How do you cook?

I'm hoping we can keep our electricity consumption below 3500-4000 kWh per year, although we have to heat and cook with electricity, and at one point we will also start using electric vehicles (bikes, perhaps scooter, car will be difficult). 60 cents per kWh is also nice, by the way, here in Austria we get 6-10 cents!

Bulkhead inside the house are made of heavy compressed mud brick which accumulate the fresh during the night  (we just need ventilation and we open windows) and restitute it during the day. Compressed bricks have a interesting capacity of "thermal phase displacement" during 12hours and it works both for the refresh in summer and heating in winter.

This is really awesome. We wanted to do the same as a house built of wood and cellulose as insulation doesn't have that much heat retention capacity. But then the gentleman who planned our house said that the weight would be too much (we built the house on concrete posts). If I would've known this beforehand I would've let them make a couple of extra concrete posts to support the walls.

What we're doing now, is mix loam from our plot with water and wood shavings, let that dry and then put it in the walls that are closed off with laths, which will be plastered with loam in a couple of weeks. This way we still get some mass in the house. The materials are ultra-cheap, very eco, but a lot of work, of course.

Here are some images...

Making of:



Drying outside when weather permits:



Drying inside when weather forbids:



In the wall when dry:



Close-up 1:



Close-up 2:



I'm hoping for satisfying results with regards to acoustics, and good temperature+humidity compensating properties.

[Neven]

And after watching this video I like your house even more (especially the toilet and the constructed wetland; I hope to have something similar up in a year or two):

[yan]

Neven

Oups    I mistake ! 1600 kWh / year of electricity consump it is for each family ...so for both it is near 4000 kWh / year. We do not make particular efforts: just class A++ appliances, led and fluorescent lights, laptop computers, electric bike. And now we have one 250 Wp solar panel (with micro inverter) directly plug into the house, production is not sold to operator. During the daylight electrcity feed directly the house and we buy almost nothing to the network (so we buy electricity for cloudy days and nignt). You can see the panel on the photo of the garden published above.

I m quiet confident  you can achieve 4000 kWh / year even with a heat pomp.

Questions on your solar-roof: do you sell your surplus production to the operator or your entire production ?  How much cost the electricity you buy ?
Yes the feed in tarif is very hight for us and it helps a lot to pay the house (near 18 000 euros / year !). Our contract with operators was delivred in 2009, now the conditions have decreased for the newcomers: resale tarif is only between 14 and 27 cet / kWh, depends on the size.

The question of thermal inertia is very important for passive house and we choose a concrete basement at the conception for this reason: or interior brick walls at the flor weight 20 Tons and of course it would have been impossible to suppport it on a wood flor. At the first floor we partially do same as you did: mix loam with little piece of straw, thickness between 2 and 4 cm. Result: not only it is nice for the eyes but it is quiet good for vapor regulation and inertia. Not as good as big wall of bricks of course, but clearly better than classical houses with polysterene bulkead . Anyway you should obtain a good vapor "natural" regulation and you will also appreciate a good sensation of comfort, thurthermore it is good for health (no cold), acoustic should be good too.

Question for heating: what will you use ? heat pomp or wood stove or else ?

My motivation for the dry toilets was partially induced by that joke:  "When you affirm to an African that every day you use toilets with drinkable water, guess what does he answer you ? He answer: I don't believe you !"


Laurent
I did not know that there was a litlle "controversy" between Holmgreen and Hopkins about "How can we save us and the planet". I'am fan of both men but...perhaps a little more fan of Hopkins who is so positive and federate this powerful worlwide movement. My point of view is that the most important is to be able to hear deeply inside you and do things that fit you the more, not suffering from the others. In my case I am very conscious that I Love Mother Earth, resilience and solar energy so I simply act in that way and I appreciate a lot to exchange experiences with others.

[Neven]

Oups    I mistake ! 1600 kWh / year of electricity consump it is for each family ...so for both it is near 4000 kWh / year.

That is still a very decent number, to put it mildly.

Questions on your solar-roof: do you sell your surplus production to the operator or your entire production ?  How much cost the electricity you buy ?

I sell the surplus. Electricity costs around 20 cts per kWh here. I hope in a year or 2-3 to add a battery system to increase our use of self-generated electricity from 35% to around 75%.

Question for heating: what will you use ? heat pomp or wood stove or else ?

We will try infrared heating for a winter or two. If we're not happy with that we'll add a wood stove that also heats water that can be stored in the 300L tank attached to our warmwater heat pump.

The question of thermal inertia is very important for passive house

Indeed. One interesting aspect I read about while designing the house, is that you really need heat retention capacity (if that's the right word) if your passive house has a lot of windows. Less windows means less heat retention capacity needed, but not too little windows, of course. Because windows are more expensive than walls (that have better insulation), and because in this part of Austria we get long periods of overcast skies during autumn and winter - and also a lot of fog where we live - I've tried to find a balance between the two. I'll have to see how it works out, because I found it impossible to calculate.

One last question, Yan: do you use any ventilation system with heat recovery?

[jai mitchell]

I am very favorable to dry toilets, I know a family that has used this technique for years.  They produce almost 3 cubic meters of soil per year, good for gardening (after 2 years) using a method developed here:  http://humanurehandbook.com/

they are 4 in their family.

1600kwh per family per year is very good. 

I use an air to water heat pump it uses 1/2 of normal electricity to heat water http://www.hotwater.com/water-heaters/residential/conventional/electric/voltex-hybrid-electric/

for heating I like to use passive heat (windows, good insulation, large thermal mass (concrete subfloor, etc.)  however I have found a new type of design that uses passive solar for rooftop heating, very innovative they use recycled aluminum cans. 

If you heat with electricity and have a contract with your operator for 60 cents you will make money with this kind of system: 

If I was to make this for myself I would make the collector area airtight and install a fitting so that I could pressurize it with sulfur hexafluoride so that it is thermally insulated.  This should be able to produce significant heating on even cloudy days.

I am very impressed with your beautiful home!

[icefest]

Sulfur Hexaflouride is also one of the most potent GHGs yet discovered, and IIRC banned for several uses in the EU.

Argon conducts only slightly more heat and is much, much better for the environment.

[yan]

Neven,

You are absolutely right, it's almost impossible to calculate heat retention/inertia for a individual house. In our case we follow the advises of a very experience thermician man (he design compressed brick houses since 1982 !) who never use computer for his calculation, juste simple ratio, ex: % of glass / mass of ground floor.

Thermal inertia is link with heating system. I understand that it is not the sun that will heat a lot your house during winter, so the infrared will come from "something" inside the house and will have to be stacked has much has possible in your heavy loam walls. My feeling is that a small wood stove will probably be the best solution for that kind of fonction, you just have to chose correctly where you install it, much possible at the center of the house and much possible near a wall with thermal inertia.  I suppose that in Austria it is commun to see wood stove in recent houses ?

We have a simple ventilation system. Air comes from the basement and is evacued with un extractor (manually adjustable 30 to 100 m3 /h) situated in the bathroom of each family. And we have an extracting surplus with the fireplace leads during the winter. Contrary to traditionnal non-ecological houses we don't have a lot of humididy to extract mechanicaly because all our peripharal walls allow vapor to come through and it will be the same thing in your house, humidy will be partly absorb by your loam walls and partly exchanged with exterior through your wall in wood and cellulose wadding. On the over side ventilation don't make us loose to much eat or fresh because wall have lot of inertia. Humidity is a fondamental parameter for the "sense of comfort" and good health of people who lived inside the house.

I'm also interested by a battery system, not this year but soon I hope. I expect good news for price decrease with multiplication of new electric cars and Tesla Giga-factory...and in he same time it would help solve CO2 emissions in transports. I'm quiet confident that solar pv + battery storage is going to be one major solution to AGW all other the world. What do you think ?

[Jim Hunt]

Hi Yan,

I'm quiet confident that solar pv + battery storage is going to be one major solution to AGW all other the world. What do you think ?

I have much professional interest such matters, but I'd describe my view as "hopeful" rather than "confident". Based on my experience here in the UK, the politicians that wax lyrical about "Enabl[ing] new low carbon technology to be deployed" have no idea what they are talking about. See for example:

http://www.V2G.co.uk/2014/03/uk-smart-grid-vision-lukewarm-on-v2g/

[yan]

Hi Jim,
Yes sometimes I 'm very positive about difficult subject such has CO2 emissions from transport. I recognize and assume that "confident" is rather optimistic. I have friends who have electric vehicule and a few who recharge it with a solar roof, it works pretty well. I'm not shure that V2G or V2H will be necessery, it seems complicated. I would prefer 1 small battery pack for home (5 to 10 kWh, connected with grid), and 1 electric car without V2G fonction.  I think that it will greatly depens on battery prices in the near future and political/strategical decisions from grid operators and governements.  Several variables...the future is never written in advance.

In real life for transportation, since 8 years I mostly use a lovely hybrid electric+human vehicule, photo below...

[etienne]

Hello,

I have two questions regarding humidity management.

The first one  about the humidity sealing of the house. I heard both therories, that humidity should be able to go through the walls to allow you to see if water finds a way in, or that the house should be totaly sealed because when humidity leaves the house on the outside walls, it uses the heat of the house to evaporate. I have always prefered the first option, but I would like to hear what other people think about it. If you choose the first option, you also have to select materials that support humidity for the house finish.

The second question is about the ventilation and humidity. My house is a traditionnal concrete house with an ouside insulation built in 1999. I have an Aldes both ways ventilation that's very basic but already with a heat exchanger. Excepted when the temperature is permanently under 5°C, I am very happy to get the humidity out of the house. I get so much humidity from cooking, drying clothes, taking showers... I need a humidification maybe 3 weeks a year, excepted this year that was soo warm that I didn't need it at all.

Best regards,

Etienne

[Jim Hunt]

I'm not shure that V2G or V2H will be necessery, it seems complicated.

Some sort of (low cost!) distributed energy storage will be necessary, or so it seems to me at least. Surely having two battery packs is even more complicated than just having one?!

In real life for transportation, since 8 years I mostly use a lovely hybrid electric+human vehicule, photo below...

I largely rely on just human power! If I want to go long distances the UK EV infrastructure in this neck of the woods isn't up to the job as yet, unfortunately.

[Bruce Steele]

Yan, Your completed green living applications are truly inspiring. Gardens, electric bicycle, wood stove, solar electricity in amounts adequate to sell to the grid, multi-family habitation and even sharing your vision are, as a package ,as complete as anything I have ever seen. Kudos and something to strive for.  May there always be peace in your home. 

[icefest]

Jim I see your public transport even come with horns.. 

Personally, what I'm hopeful for is the combination of PV + storage for domestic use.  With wind taking up a significant amount of slack in winter (when it has a higher CF anyhow). By the time batteries are cost efficient solar panels should be cheap enough that most small to medium businesses will switch as they mainly use daytime electricity. I'm expecting most hydro to be used for load leveling. The grid will probably survive but I'm expecting major restructuring of the generation giants.
A misfortunate side effect is that this will probably result in either curtailment of energy production in times of high supply, or a development of a niche industry using the intermittent but cheap excess electricity. 

[jai mitchell]

When using a wood stove it is very important that the air intake to the fire comes from outside the house.  Or else you take the warm air from the room where the firebox is and send it up the chimney!

when I installed my external air source (drilled a hole through the floor) I reduced my wood consumption by 15% and raised my comfort levels significantly.