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14 Answers

HVAC Retrofit for 1918 Colonial Revival in CT

My husband and I own a 1918 Colonial Revival in CT... where summers are hot and humid and winters are cold. We bought the house 4 years ago. But we're not spring chickens... we're in our 50s so we won't see as much return on investments as say... a younger couple might. (We have no children but my husband's elderly uncle might stay with us in Feb. 2016 so we need efficient heat for him.) We also don't have a big budget - plus our house is in a neighborhood where the houses are losing value, so we don't want to spend a tremendous amount on renovations.

In Green products and materials | Asked By Margaret Tehan | Nov 22 15
0 Answers

Does EPS shrink with time?

On the following link a comment was made that I have concerns :
"On the foam, two layers is better than one, with seams taped on both layers, and overlapped by a foot. Over then next 40 years the EPS is going to shrink a bit, but the performance hit won't be too bad if the seams are overlapped and still reasonably air-tight."
Answered by Dana Dorsett

In Energy efficiency and durability | Asked By Edwin Perdomo | Nov 23 15
3 Answers

Radiant floor in very thick slab

I'm working on a project (climate zone 4C) that will use a thick (~16") raft slab due to poor soil conditions and the client is interested in a radiant system as well.

If the pex tubing were held approximately 2-3" below the top of the slab and the entire perimeter and sub-slab were insulated to R-20 would it make sense to use a radiant system?

I imagine at the very least it would be a huge flywheel that a very long time to heat up or cool down, so you'd have to just set the temperature and leave it alone.

Any thoughts?


In Energy efficiency and durability | Asked By Daniel Stewart | Nov 23 15
4 Answers

Vapor barior on SIPs in a hot humid climate

We have been asked to repair siding on a sips panel house in a hot humid climate. Our client has been advised to have us put a vapor barrier over the panels before installing the siding. This will essentially put the OSB between two vapor barriers... in a hot humid climate. This does not seem like a good idea. What do you think?

In Green building techniques | Asked By Hugh Stearns | Nov 20 15
10 Answers

Total energy efficiency -- ROI and what else to do


Very much appreciate everyone's feedback. I would like to give a quick overview of the improvements I have performed to my new (to us) home and look for feedback but additional DIY improvements to save energy.

In Energy efficiency and durability | Asked By Justin Brown | Nov 17 15
7 Answers

Questions on retro insulating a 1968 Cape Cod style home in Zone 5 (northeast Penn.)

I recently bought a 1968 cape cod style home in NE PA region 5. There is a full below grade basement, main level, and of course the upstairs bedrooms with dormers / kneewalls and a tiny crawl attic. There are hatches to enter all these spaces. The bedrooms closets occupy space between the attic and kneewalls (sloped drywall against the roof rafters at top of closets). Presently there is R-13 fiberglass batting in the kneewalls, the roof rafters above the closets, and on top of the drywall ceilings in the bedrooms. So the kneewall cavities and the attic are unconditioned.

In General questions | Asked By Ryan | Nov 21 15
2 Answers

Converting can lights

I have 8 recessed/can lights in my home. They are not ICAT rated, so there is currently no insulation around these fixtures. No air sealing, either. We're adding cellulose insulation within the next few weeks, so I'd appreciate some advice on how to deal with these dang lights.

We priced replacing with ICAT fixtures, but it's too expensive. Also considered removing them entirely, but that's even more expensive and time-consuming. We ordered some LED retrofit inserts (Cree C6), but they are too bright (625 lumens) and the depth of the light causes shadows that we dislike.

In General questions | Asked By Green Heron | Nov 22 15
4 Answers

Insulating with nailbase panels

I've been thinking about building with SIPs and am waiting for a quote from a local dealer. But, I've also had an idea about using nailbase panels that could be cheaper. What about framing with 2x4 studs and then sheathing with nailbase panels but with the foam side facing in, and the OSB side facing the outside? I could then spray foam the interior a couple inches, and be able to attach cladding directly to the OSB. Any thoughts on this? Has anyone tried this before or think it would be effective? (Building in Michigan - climate zone 5) Thanks.

In Energy efficiency and durability | Asked By Brian W | Nov 20 15
2 Answers

Using well water for air conditioning

A random thought occurred to me while I was thinking about the Chiltrix system. For air conditioning, water at about 55 degrees would be circulated through the fan coils. That is about the temperature of the water coming out of my well all year. If the system was only used for air conditioning, could the well be the source of the cold water as opposed to running a compressor? I don't see a problem with this idea, but I expect that if it was simple at least some people would be doing it. Am I missing a major flaw?

In Mechanicals | Asked By Reid Baldwin | Nov 21 15
2 Answers

What is the best way to have a 28' chimney pipe cleaned on a high efficiency wood stove?

I just wasted 48.00 and was told my high efficiency wood stove can not be cleaned from the inside up because of the smoke baffle inside of it? I didn't even know it had one. They are telling me I will have to rent a cherry picker because my roof is to high and steep to clean it from above. Plus I assume now my chimney cap is not the correct one because I found out it leaks. Not around the wall but down the pipe, I found my ash drawer full of water. Other than getting rid of my wood stove I wonder if you have any comments or suggestions?


Susan Evans

In General questions | Asked By Susan Evans | Nov 21 15
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