We have an electrical contractor locally who gives work away..no mark up on material low labor rates..so to install fully zoned system yes he is cheaper than a contractor installing hydronics. I'd have to agree w Rob, gas is not always most economical choice, I believe there are still areas where they have electric heating rates that are lower per therm than ng. Plates are not always needed it depends on the load. I also agree that staple-up is less than desirable..I have done a fair amount of floor warming and combos with joist space heating with satisfactory results. Eric

Life is a compromise.

No plate, no problem.

$30,000+ geo, go ahead.

Refined power, for crude resistance heating (boiler full time, geo 25%+ in cold climes) have at it.

Without gov't. tax credits, the market wouldn't exist.

I've done math on several projects that say you're wrong, but the credits definitely have made more of a market of course. Just takes a big load to make sense.

and big loads don't make sense... but they are the norm.

Superinsulate is by far the way to go... then the load is small... then... GEO doesn't make sense. But the newest air source heat pumps do if combined with heat storage so as to collect heat during highest outside temp.

aj

or move to an open window paradise... Tahiti


what an idea... my next post may have to be from under a palm tree.

I too have been leaning toward foam for a decade and just foamed my own remodel, hot roof to rim joist. It is a hedge against fuel hikes, quiet and comfortable.

Fuel prices won't diminish its value, infiltration controlled, low fuel bills regardless of heat source.

Most of my work is with radiant and condensing boilers, but my boilers are getting smaller (and design temperatures lower) as I specify more foam, which requires the least amount of labor, has zero maintenance and lasts the life of the house. No heat "source" comes close.

Dense Pack Cellulose, Baby. half the cost, twice as green.

Green is as green does.

I use a lot of cellulose, but long term, the foam will win. A vapor barrier is only as good as the guy putting it in and doesn't belong in basements in any case.

The steel shed will get foamed walls and cellulose ceiling (so I can change my mind for mechanical later).

Off topic question... where does one buy wholesale cellulose instead of big boxes?

Albany, NY... I think smartwall... you are cell pro right? Maybe your install price is as good as buying material at the boxes. I need to price a project with you. My insulation guy does not do cell... I have only done cell in house.

wholesale cell cost anyone... and suppliers?

I don't think the foam will win, long term. once it offgasses it's not that much better than cellulose anyway.

though I do like rigid EPS these days. cheap, open cell, all outside a zipwall. 6-3/4" on our shop appears to give a very nice shell with no SIP joint issues.

On a renovation such as mine, the 2x4 wall won't allow enough newspaper to meet the requirements of the 2009 International Energy Conservation Code (IECC). Its foam baby! heehehee

Not to mention capping the joists in the attic and infiltration.

If you have 2x6 construction and wet cellulose applicator in the area your all set. If not, you will find closed-cell foam efficient and structural. I love the stuff.

foam might meet the requirement, but after offgassing you get what... a extra 1.5 R per inch? assuming it's mixed right?

honestly, while I like it from a heating perspective, I have some serious reservations about site mixed toxic components. Rigid sheathing I think is much safer. and it beats thermal bridging.

but everything has its place I suppose.

I think your numbers are a bit off Rob.

http://www.henry.com/fileadmin/pdf/PERMAX%20BROCHURE.pdf

No smel,l no sheet rock for months now. Conservation IS green.

I get more off-gassing from a new service truck.

all closed cell foam offgasses. It's not an odor thing. it's a loss of R-value thing, and the gasses that are released are not so nice for health or the environment either (fluorocarbons). Permax is just polyurethane foam. Read up:

http://en.wikipedia.org/wiki/Building_insulation_materials#Spray_polyurethane_foam_.28SPF.29_Insulation

the aged R-value of the stuff is typically R5.5 to R-6, but I have struggled to find any truly long term numbers. most MFGs, when they even use aged R-values, seem to use a fairly short term value. I suspect, personally, the final value is more like a 5, but I can't pretend that's a scientific assessment.

Add the possibility of a poor mix on site and its impact on both offgassing and R-value, and I would much rather keep most of my foam mixed at the factory and brought to me rigid, and open cell (no fluorocarbons).

that said, I used close cell spray foam in a part of my own house: open crawlspace, needed underfloor insulation that was also impermeable to moisture/vapor. Not much else would do. But if I have a choice in the future, you can do cellulose way cheaper... you can do external rigid EPS way cheaper as well, with no thermal bridging or separation from expansion/contraction as well.

so those are my preferences. but as you say, the most important thing is conserving. spray foam is way better than fiberglass. I'm just nitpicking about preferred ways to achieve that conservation. Cellulose and EPS are cheap, wonderful products.

As the majority of my work in renovation in cold-climate-heating-systems and given the general weakness of other professionals in assessing and specifying "the rest of HVAC system" I am forced to control or consult on HRVs, cooling, windows and yes even insulation.

Yes; factory specification is easier to achieve- in the factory, but the real world is out here. I have installed (and removed) nearly every insulation used since the turn of the century, witnessed blower testes on most of them and found craftsmanship to be a the key factor in there efficacy -short term and long. As for closed-cell polyurethane, I rest my argument on the "disadvantages" listed in the link you provide.

Most of the alternatives are labor intensive (labor may maintain the listed value but will never increase same). When you buy closed-cell foam, you are likely to get what you pay for. As for quality of installation, brand matters if training and quality control are a verifiable component of field operations.

Being GREEN does not mean you are averse to the use of ALL chemicals; I am using electro-chemicals to type this message as a matter of fact.

I guess that's where we disagree. I see the "disadvantages" on the wiki as pretty significant. *not enough to avoid use entirely*, but to prefer other products without those disadvantages whenever possible. In your case, perhaps that is not possible. In my crawlspace situation, it was not possible to avoid it. In most cases though, it is.

We used all EPS wall and cellulose ceiling in our shop, it was very cheap, no benzene around, no immune system destroying components to possibly fail to mix properly, no VOCs, no HFC's, and we have successfully achieved a supertight building with no chance of separation from the framing components, and nearly completely avoided thermal bridging (just the screws for some exterior strapping). I was able to get more R value at a better price than I could with closed cell foam, which came in at literally twice the price.

If I don't need a couple extra R per inch, I'd advise it every time. part of being green is healthy environments. and honestly, it's almost never an inch to inch comparison. No one fills 2x6 stud cavities with closed cell foam. That would be ridiculously expensive and way beyond any economic payback calculation's range with any but the most "fire is raining from the sky" estimates. So the final comparison is usually a lot more in favor of modern densepak than a per-inch comparison would indicate, except in particular cases like yours where space is a premium and it will actually be filled.

For anyone interested, we used the REMOTE wall system, we're very pleased so far http://www.cchrc.org/remote-wall-study . No insulation in the stud cavities (no drywall either), 6" of EPS all around, staggered layers.