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0 Answers

You told someone that they could patch open cell foam insulation with

You told someone that they could patch open cell foam insulation with spray insulation from the hdw store. The spray "stuff" that I am familiar with is of the closed cell variety. Is it that to which you are referring? Please advise, as I have some holes that need repairing.

Asked By Kenneth Sayers | Jul 21 16
10 Answers

What is the best way to attach the sub-slab vapor barrier to the walls?

In regards to laying the 6 mil poly vapor barrier down prior to pouring the concrete slab...

Should the poly wrap up the side walls higher than the concrete floor level, and then be attached to the walls with caulk & furring strips that are anchored to the walls with Ramset nails?

- or-

Should the poly just barely wrap up the side wall, and be taped to the wall (with Tyvek tape or similar) so that the poly and tape are encased in concrete after the floor pour?

-or perhaps this connection is unimportant, as the slab will get caulked on this slab-to-wall joint

Asked By Adam Peterson | Jul 20 16
1 Answer

Does Low-e glazing affect plant growth?

There seems to be an ongoing discussion about this subject and not a final conclusion yet, I imagined maybe somebody on this forum could know better.

Asked By Jose Castro | Jul 21 16
10 Answers

R-35 wall assembly for a 4C Marine climate zone

I am about to build on a 85" rainfall, 6000 HDD and no cooling system (I can withstand a little heat in summer)

I'm thinking of (from outside in)
* 1" wood siding
* 1" of air gap with 1x3" furring
* asphalt paper as WRB and air barrier
* 3" 2pcf EPS as R10 sheathing,
* A 10" double frame wall filled with a total * of R-24 polyester insulation
* asphalt paper as air barrier and vapor retarder
* 3-4" interior wood finish

(see attached image)

Asked By Jose Castro | Oct 29 14
8 Answers

Dehumidifier: running too much OR poor energy efficiency?

I just installed a 30 pint dehumidifier in the basement of my single story 900sqft house.

It uses about 4kWh per day to maintain a set-point of 55%, as measured by a Kill-a-watt.

I'm in Chicago, Zone 5.

My electricity bill without the dehumidifier from March-April was about 200 kWh/month.

Last month, with the dehumidifier turned on midway through saw a usage of 240kWh/month. A/C has not been used yet.

How can I determine if that 4kWh energy usage is due to it just running too much (e.g., too small for conditions?) or if the equipment just takes too much energy to run?

Asked By Jeff Watson | Jun 6 16
33 Answers

Dehumidification vs. ventilation in an existing house

I have done significant air sealing of our 1930s cape cod house in Virginia (climate zone 4) and it only recently dawned on me through reading various GBA blog posts that this air sealing is probably the cause of our high indoor winter humidity levels (ranging from 55% to 70%)

I understand that adding ventilation is the correct way to go, and the bathroom exhaust fan approach seems the most cost effective. However, before doing this I have a few questions.

Asked By Timothy Godshall | Jan 4 15
7 Answers

How to choose someone for an energy audit?


I am looking to do an energy audit of my house. What should I look for in regarding selecting a company/individual - certifications, etc. What qualities would a good auditor have - what questions should I ask and what should they be asking of me - utility bill history, etc.


Asked By Joe Watson | Jun 8 16
3 Answers

Is an air space between a ceiling and SIPs a problem?

I have a timber roof system that goes like this.
timber rafters
plywood with a flooring glued to it and fastened down on top of the timber rafters
suredeck membrane (to protect the plywood) and double as vapour barrier
2x6 strapping on top of the plywood to facilitate electrical
8 1/8" sips
synthetic membrane and peel stick for eaves protection
laminated shingles
Should I be concerned about the 1.5" space between the top of plywood and bottom of sips.
We are going to be extra ornery about air sealing the sips.

Asked By Marty Munroe | Jul 20 16
33 Answers

Direct vent vs. power vent gas water heaters

A recent blower door test/audit has alerted me to the fact that my natural draft hot water heater can backdraft in worse case scenarios (range hood/clothes dryer/bath fan on). It seems to reverse back to a correct draft after a few minutes. It's only about 6 yrs old, so I hate to replace it, but not as much as I hate the idea of the back draft.

Asked By Erik Addy | Mar 8 16
4 Answers

Insulating cold water pipes

I'm getting a lot of condensation on my cold water pipes. The house is plumbed with pex, and most of the condensation is collecting on the copper and/or brass fittings.

Asked By Calum Wilde | Jul 20 16
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