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4 Answers

Ground Source Heat Pump Domestic Hot Water efficiency

I understand that a desuperheater captures the heat that is naturally lost by running the heat pump. Is it capable of supplying all the domestic hot water in a typical home? Does this mean that it is essentially using 'free' energy and the Energy Factor of this DHW system is infinity (ignoring pump consumption)?

Asked By Nick Sisler | Apr 18 13
4 Answers

Is fiber-faced polyisocyanurate OK for exterior insulation board?

Hi everyone....I am preparing to get back at the exterior of my home renovation project now that winter in New York seems to finally be at an end. I plan on installing exterior rigid foam over my sheathing with vertical furring to create drainage plane and a nailing surface for my siding.

I have access to 2" polisocyanurate insulation with a black fiber facing. (Originally intended for a bitumen roofing application.) The material is NEW and is about 1/3 the price of XPS or foil-faced polyiso.

Asked By Brandt Minkler | Apr 17 13
1 Answer

Converting my attic to a conditioned space

I am planning on converting my attic to a conditioned space so that I can put an air handler up there. I read a great article here on what my options are as far as venting. I do have a couple questions on this though.

My roof uses 2x6 trusses. I had new shingles and vents installed about 7 years ago. They used the can vents. I was going to install a ridge vent and just leave the can vents there and use the rigid foam to create a 1" ventilation channels and use the spray foam over that etc...

Asked By Dino Zakos | Apr 18 13
8 Answers

Siding remodel in Climate Zone 2A (Houston)

My research has lead me to (inside-outside):
Drywall -> Roxul (rockwool) -> QuietBrace (sheathing) -> perforated radiant barrier -> 1x4 cedar furring -> Hardie lap siding

I picked QuietBrace (fiberboard) due to its permeability factor. I am worried about foam (polyisocyanurate) in such a humid environment such as Houston. Another option is just straight up plywood. I'm not worried about structural integrity of the material since my house doesn't currently have wall sheathing on it.

Asked By Kiya Lee | Apr 16 13
1 Answer

Do you recommend turning off water to gas-fired water heaters when going on vacation?

Do you recommend turning water off wham you are going to be away for extended periods of time?

To gas hot water heaters.

Asked By Donald Landis | Apr 18 13
7 Answers

Information about "Best Available Technology" reduced-nitrogen septic systems

I'm building in Maryland, where the state just passed a law requiring homeowners to install "Best Availalble Technology" septic systems. The State has approved a few models - Singulair TNT, Hoot BNR, Advantex and a few others. Because these technologies don't seem to be widely used and they're kind of new (which concerns me), I'm having a hard time finding objective informaiton about which one to choose.

Does anyone know of a source for good unbiased information or comparisons on these types of septic systems?


Asked By Colby Pierce | Mar 10 13
4 Answers

Is there a building code on deck board spacing?

I have a flat roof and my contractor built a cedar board floating deck. the area is 16'x20' range and he made into 4 section, 16'x5' each. the boards are tight fit(no space) and also tight fit to the edge wood board( the wood board sit on top is metal capping). the nails are all sunken under the wood surface. One winter with snow/rain, I had to shelve the snow off the roof since the ice/water sit on the cedar boards. there was a leak(this roof did not have leak before the new deck). I tried to find out where the leak was, but the boards were all frozen together, like a big ice block.

Asked By Julia Ko | Apr 16 13
3 Answers

Housewrap alternative?

Building just outside of Memphis, TN - the home is all brick with OSB sheathing. The builder doesn't think housewrap is necessary- when they spray paint the soffit and fascia, they also spray the OSB (not thick, not full coverage, but a thin breathable mist)- does this produce the same benefits as house wrap?

Secondly- using vinyl windows, they do not spray foam aroound them as they say if the window gets moved during construction they cannot adjust the fit once it's been foamed. True or BS?


Asked By jim mcgahey | Apr 16 13
4 Answers

Suitability of Rainscreen Wall Design

I am working on a wall design for a small house that we are going to construct this summer in Oklahoma. My planned wall from the inside out goes as follows:

1. 1/2" gypsum
2. 2x6 stud framing, 24" O.C.
3. Cellulose insulation in the cavity
4. 1/2" plywood
5. 1" XPS
6. 30 # felt
7. 2x4 vertical furring strips attached to FastenMaster specs (3/4" material seems inadequate for siding fasteners)

Asked By Jason Whitacre | Apr 16 13
3 Answers

Sherwin Williams has a paint product that is sprayed or rolled on the underside of the roof deck that acts as a radiant barrier

Does this product work? Or should I use the "bubble wrap" stuff?

Asked By roger steinbrink | Apr 15 13
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