I know this guy trying to get Platinum LEED certification for the house he and his family are remodeling. He built an interesting above-ground rainwater catchment system that he was telling me about on the phone a couple weeks ago.
We also talked about insulation. The fab Gf and I are using a closed-cell polyurethane-based expanding foam. This is not nice stuff, but it is extremely energy efficient (R value of 6.87/inch), seals as well as insulates, has a low vapor permeance, and it’s not a food for anything, so it discourages critters from settling in. Part of the challenge of building is making these kinds of compromises---it saves energy, but it’s not the greatest thing for the environment; it’s got a lot of recycled content but uses a lot of embodied energy; it has great performance but isn’t recyclable; it’s amazing, but it’s made in sweatshops; it’s amazing, but so expensive, we’d have to grind down the installers to afford it…
Anyway, Robert was also using a foaming insulation product, but his was soy-based and he claimed it was better for the environment. I checked the data on the product and he was right---but the product only used a percentage of soy, not all, and it also had some bad stuff in it. Also, it was open-celled and had a lower R-value. Didn’t quite fit our needs. But he liked it enough to invest in the spray equipment that lets you lose some of the bad chemicals (the propellants account for a lot of them) and saves you some money since it’s more efficient. I was hoping he’d let me use it.
A week or so ago, I got a call from our heating guy, Colin, telling me that Robert had had to hire a crew of Mexican guys to scrape out all of the foam insulation they had sprayed.
After spraying the whole house, Robert had had what appeared to be a massive allergic reaction to the foam.
He’s okay. Physically. But this is a $21,000 (and counting) mistake, a mistake hard to rectify when you’re out of money. I told Colin that if Robert needed a sympathetic ear, I’d come over with a bottle and a box of recycled tissues. Colin said that he didn’t think Robert should start drinking.
This is terrible for Robert. Trying to do the right thing and it bites him in the ass.
I’m allergic to everything. But I’ve worked with the foam insulation were going to be using---sprayed a chunk of the ceiling a few weeks ago, in fact. I’ve never had a problem with it. I got a headache the last time, but that was because of muscle strain---lying on a shelf, reaching up and over, keeping my head out of the way because I was wearing my mask. It was a whole thing with ladders and heat and getting foam insulation in my hair and other unpleasantness.
So part of me wonders if it was the chemicals. There’s a good chance it was---people are sensitive to them and they’re pretty harsh if you breathe them in. I don’t know if the foam he was using off-gases after 24 hours. The one we’re going to use doesn’t. I do know, though, that if you want to spray really thickly, you do it in layers. Put on the first layer and let it puff up and cure. Then spray on the next layer. If the layer is too thick or sprayed on too soon, the chemicals can’t get enough oxygen to react, so you have chemicals sitting there uncombined and they will off-gas over time if they get the chance.
Another thing, though, involves the framing materials. Wood is vulnerable to weather. I know Robert’s house was exposed to rain during building and parts of the structure got wet. Usually it has a chance to dry out, but Robert used a special rain screen material on the exterior of the house.
You often see weatherproofing like Tyvek or tarpaper on the sides of houses before the siding goes on. These waterproof membranes function in different ways, but one way is to allow liquid water to flow to the bottom of the wall and drip off, while water vapor from the interior is released out the building envelope and through this barrier. Some of these moisture barriers are pretty sophisticated. Anyway, the rainscreen system Robert installed uses a new product I’ve never heard of. I wonder if it didn’t trap moisture in the framing---something that usually will result in rotting wood that you find out about years later. If that’s what happened, the heat generated from foam insulation may have vaporized the moisture, taking any mold, mildew, or fungus that will grown on anything here, standing still or not. A lot of people are allergic to that stuff but don’t know it until they reach a tipping point.
Unlikely, I know, but I am puzzled about this. I’m not going to say anything to him, though. He’ll figure it out, but he needs to remind himself that disaster is always hovering over you, ready to drop on your head with a skullcrushing, heart-shattering thump.
Colin says all the foam insulation has been scraped off and is now sitting in heaps, with particles floating in the air. Terrible. Terrible for the company that made the foam (if that’s what did it). Terrible for a nascent industry trying to get a toehold in a very competitive business. Mostly, though, terrible for Robert and his family. And what’s he going to do with all this foam? There’s no way to recycle it.
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I keep hoping for somebody...
to come up with flat insulation that isn't foam or fibre, that's about 1/2-inch thick, that I could simply apply to the interior walls and then add trim and paint. Wallboard with R value.
[ ] Very tepidly voting for Obama [ ] ?????. [ ] Any mullah-sucking billionaire-teabagging torture-loving pus-encrusted spawn of Cthulhu, bless his (R) heart.
You'd have to tape it or caulk it
Sealing is the challenge. The seams and any punctures would have to be thoroughly sealed. For example, an electrical receptacle. You have to cut around the receptacle, which means losing that insulation. If air can pass through, it can bring moisture and if there's any difference in temperature, you have condensation. Then wet. Then rot. And then the carpenter ants hear about a new restaurant in town.
So your dream product has to insulate and seal. I'm not saying it won't work, I'm just saying I haven't seen anything like it yet.
The foam works as it seals and insulates, it can match any shape, it will last forever (provided it's out of the sun), it doesn't require any real skill to install (hell, I did it). It has it's downside---made of bad stuff, it lasts forever, there's no current recycled use for it (that could change, though), it's expensive, and while Robert is the first person I know to have had a bad reaction, that doesn't mean he's the only one.
Economics
IMO the problem isn't losing $21,000 on insulation - it's spending that much in the first place.
Fiberglass is much cheaper and I'd be surprised if other than the energy consumption used to produce it, it has any environmental downsides - it's made from sand. I don't believe you can be allergic to glass (you can itch a little installing it though). Fiberglass also doesn't burn, and therefore doesn't give of toxic gasses in a fire (like cynide) as most foams do.
It's also easy to make a closed envelope. In our first house, we built with 2x6 stud walls stuffed with fiberglass. We sheathed with 1 inch styrofoam under the siding. On the inside, we applied a 6 mil poly vapor barrier with no breaks (except for windows and doors of course).
Then we applied 2x2 furring along the studs and plates. Then nominal 1 inch solid wood paneling over that. All of the wiring in the outside walls came up from underneath, inside the vapor barrier in the 1 1/2 inch space behind the paneling (we had a full bsmt and did our own electric). No plumbing in the outside walls (then the pipes never freeze). We bought a couple of cans of foam for something, but I don't recall what.
We could heat that house (about 1500 sq ft) with less than 3/4s of a cord of hardwood in WI, where winters routinely hit -20F or lower. We had a lot of glass on the south facing wall too, so even at -20F we didn't build a fire until the sun disappeared in the afternoon. And we were home all day, every day.
Our current house is 10 inch logs in a milder climate. It'd take us somewhere around 200 years to pay off $21,000 in insulation (assuming no heat at all and normal interest rates), and would probably increase our carbon footprint besides.
Batt insulation in the roof?
Code requires R30 in the roof, so to fit enough batt insulation you'd either have to have trusses with enough depth or, if you have cathedral ceilings, you're looking at 2x10 or 2x12 members (or the equivalent manufactured products and I can't remember which right now) just to have space for the batts. So your cost goes up there. $21,000? probably not. But it would be a factor.
My electrician just insulated his house. He bought the materials and hired a crew*. It took them two days and cost him just under $5,000. I think his house is 2,200sf. Figure $2.50/sf vs. Robert's $8/sf. (additional money to get it scraped off).
As I recall (I'd have to look it up) batt insulation does have some downsides---breathing in the fiberglass particles is one. Most of it is sprayed with anti-mold, anti-fungal stuff as well, but I don't know about off-gassing. Mold and fungus don't grow in the fiberglass but on the paper or the dust that's been subject to any water or water vapor. That's probably minimal, though getting the stuff in your eye totally sucks.
I don't know about recyclability. I know critters love fiberglass batts---birds nest it, rats nest in it, and once it's squashed, it loses it's insulating value. And I don't know much about the manufacture. Tell the truth, I saw how deep our roof members would have had to be for batts and I said to hell with that. It made no sense to me to overbuild the roof so much just to hold that insulation.
The seams remain the big problem with batts. Condensation because of any break in the envelope results in water intrusion. Foaming does take care of a lot of that, especially for roof penetrations. Yes, caulk, caulk, more caulk, and flashing help (damn, you better be doing that), but very few of the available products are safe from degradation by UV, so if you don't want or can't inspect your roof every year, you may get a leak and not know until it's too late.
(Overly cautious? Yes. But if our bale walls fail, it will most likely be due to water intrusion, so I am, the clinic term is "compulsive" about this.)
Some foam manufacturers are now pushing the idea of foaming all of the intersections between materials, then running batts as normal. The testing data looks good for this procedure.
BTW, the foam we're using doesn't burn and is rated for fire protection---another plus. Most fires in bale homes happen in the roof and if it does, you're done. True of a lot of structures. Gah, I just got a shiver thinking about it.
But you're right re: the money. That is a factor of greenbuilding most people skip right past---you may be able to buy the foam, but can you really afford it? How much do you have to work, what other resources are you using, to make that purchase? It's a different way to figure ROI and sometimes the results means you don't get what you want. And then it's time to cry.
*A note about hiring Mexican guys. We generally don't hire crews of Mexican guys to work for us. The one time it happened was when we moved a tree and the company sent out the crew. I have no problems with Mexicans or people who want to work. There's plenty to do and this is the land of opportunity. Where I do have a problem is when workers with whatever papers have no protection from exploitation and are hired because the people they work for gave the lowest bid. "Lowest bid" is often a euphemism for shat-upon workers and that is just wrong.
I haven't said anything to Robert about how it was bad for him to be around the foam insulation he sprayed but okay for the Mexicans he hired to scrape it off to be around it. I don't know if he gave them respirators---I hope he did. If he didn't, then he's just another fucker. That doesn't stop me from feeling sorry for his financial situation. It is possible to feel sorry for someone who has just behaved in fucker-like fashion. Compassion is not a weakness.
This is an ongoing issue for me---greenbuilding starts with an investment in people. If you have to choose between cork flooring or paying someone decent wages, put the money in the people. Too much "Green BuildingTM" requires workers working for substandard wages in unsafe conditions or else no one could afford to do it.
Foams
I remember the isocyanurate foam insulation of the 1980s. Great stuff until people started getting sick from the outgassing. Killed the product and part of the industry. Especially bad as one friend, an expert installer, said the problem was not with the foam but with improper mixing and installation.
Oh well. Twas ever thus and I guess 'twill ever be.
Roof
Our WI house had a cathedral ceiling. Inside, the central ridge beam over the LR was about 28 inches deep (forget the width) and supported 5-1/8x9 rafters 8 ft OC (all that was glu-lam). On top of that was 2x6 T&G deck, then 6 mil poly, then 2x10 purlins (perpendicular to rafters) and then 2x6 rafters. 9-1/2 inch batts in between the purlins and (i think) 3-5/8 batts between the rafters, leaving a good air space (and vents in the soffit and at the ridge). That's around R45 with the 2x6 and air layers. The extra depth of the roof was boxed into the overhangs (2 feet all around), so you couldn't tell it was more than 2x6 rafters.
Amazingly, no one slipped on the poly (but some 20 ft 2x6s hit me on the head - 9 stitches, lots of blood).
I investigated lots of alternatives, including pre-fabbed foam roofing slabs. Every alterative was vastly more expensive. Anyway, fiberglass is cheap, lumber is still (relatively) cheap, and it took about 2-3 days to do the framing and insulating after the roofdeck was on, including an afternoon at the ER.
Our current house is similar, except the ridge beam is smaller (shorter span) and the rafters are 6x8 solid doug fir, and the cathedral ceiling/roof is a 12/12 pitch, so we get a big 2nd floor loft area "free". On top of the rafters is a 2x6 T&G deck again, then tar paper with big overlap, and then 16 inch BCIs (plywood and 2x4 I-beams). The latter are way overkill, but the county and the consulting engineer who signed off treated the inside rafters as decorative, and designed the roof on top of those for 65psf, as we're over 2000 ft. The first winter the trusses in the carport (also 65 psf rated) were popping from the snow load. We have 15 inches of fiberglass between the BCI rafters.
When they repaired the roof after the first year (5 ft of snow on the ground; ice slowly moving down the roof like a glacier shearing the metal roofing off), they checked the insulation around the plumbing stacks (that were sheared off too) and it was fine - no moisture problems. It also has soffit and ridge venting.
So yeah, fiberglass leads to thick roofs, but thick roofs aren't necessarily much more expensive.
When we built in WI, we overlapped the vapor barrier 4 feet at the seams and taped it with heavy Scotch tape. Log homes don't get vapor barriers on the walls.
As far as critters, we had no problems until about a month ago. In a log house you need to leave headroom above the windows because the logs settle. That was stuffed with fiberglass and then the casing nailed over to cover it. Because logs are round, the casing is only tight tangentially, and a squirrel started removing insulation one sunday morning above the bedroom window. I grabbed a 15 foot length of quarter-round - I have no idea why it's in the back hall, but it's an excellent squirrel "worrier".
Then I pulled off the head casing, replaced the missing fiberglass, and then enclosed the whole thing in 1/4 inch hardware cloth (galvanized screen). That pissed the squirrel off, so he is now chewing along the top of the head casing and also chewed through the nearby clothesline. Everywhere else except the windows the insulation is behind screening. For some reason though, only that one window is suitable for stealing insulation.
We hired a crew of migrants a few years ago to cut brush along our road. We paid them something around $10/hour and got nasty calls from orchard owners for overpaying them. We could only afford one day's work and that wasn't enough to finish, so they offered to come back the second day for free. Really nice people and hard workers.
You could ask your wife to knit you a squirrel-be-gone
I myself prefer a broom as a bird swatter. They don't bother the new house (the bird blocking has no ventholes, so they have no where to perch) but the little house offered them plenty of places. Hardware cloth pissed them off, enough so they would divebomb my poor blind and deaf dog.
The dog didn't even know they were doing it, but those birds would get close. I never actually made contact with any of them using the broom, but I'm pretty sure they felt my wrath.
That's a stout roof. I looked at SIPs as well and was not happy with the $$$.
So you live in a log home? That's pretty cool. We looked at those for a long time. Same thing with post-and-beam, then post-and-beam with bale infill. but that would have been way too sensible. So what do/did you use for the exterior finish on the logs? Sikkens?
Ah, well. My heating guy will be back on Friday, finally, so we start mounting the solar thermal panels for the DHW and the rest of the heating system. Lift and sweat.