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2 Answers

Will fiberglass insulation retain interior heat that a thermal barrier (foil) will not?

I have an unheated shed for gardening tools, equipment, and chemicals that has foil backed plywood walls and roof sheeting. I plan to install standard plywood to the interior walls. Summer temps average 90 to 100 degrees max so the thermal barrier of the foil should provide some insulating value to keep the interior somewhat cooler. I am concerned that winter temps that typically dip to the 20s but occasionally could dip lower, could cause something in the shed to freeze.

Asked By user-7026765 | Feb 23 18
5 Answers

Real estate appraiser doesn't care about energy efficiency

Recently had an appraisal done for a refinance loan. I have a four year-old 9 kWh solar system (provides near 100% of electricity); a one-year old top of the line Lennox Signature 98V furnace (98% efficiency, VSM, modulating burner) and a one-year old Lennox Elite 16 SEER AC.

Asked By Bic2 | Feb 23 18
8 Answers

Wall, floor, and roof build layers

A little background.

Starting construction on a small house in Texas, west side of Houston,
Climate zone 2A - wet & humid
Conditioned living space is 1280 square feet
House is being built in a FLOOD WAY, Yes I said in a FLOOD WAY
We already have approval to do this, which has taken us quite some time to accomplish.

House will be elevated approximately 6' off the existing grade on concrete filled
fiberglass pipes with re-bar reinforcing inside. I have designed a steel collar, plate, &
C-channel attachment system that our engineer is comfortable with.

Asked By von Leyser | Feb 23 18
1 Answer

SIP panels

We are thinking about building are next house with SIPs walls but I have a few reservation. We are located in central NC where it seams is always humid. The house would be ~1800 sqft ranch with a simple rectangular design. Everything I have read about the panels seems great and the ability to get a air tight house with r-27 insulation quickly and easily is very attractive.They offer polyurethane with a few exterior options such as Zip and LP Smartside sheathing, the idea of having the siding already in place seems nice and would speed of the build.

Asked By Ryan Cutright | Feb 24 18
18 Answers

Brick house insulation

All,
First of all, I wanted to wish everyone Happy and Prosperous New Year!
I would like to ask for an advice regarding a wall cavity composition. I am in Westchester County, 30 miles north of New York City, climate zone 4. I am about to acquire a brick house (tiny brick, maybe 2-3 inches thick). Single wythe, I believe. I think that brick is just decorative and is not load bearing at all. Only cinder blocks in the basement support the floor joists. Second floor ceiling joists are supported by wood framing.

Asked By Sebastian Smith | Dec 29 17
1 Answer

Sealing framing to subfloor

What is the best way to seal bottom plates to subfloors when framing? In my current house, I went around and caulked after the walls were up. Is it better to put a sealant on the bottom plate before raising the wall? How about a 1/4" Sill Seal like Denarco makes? Or an EPDM gasket? My walls are 2x8. I don't want to spend huge amounts of money, so what is most effective, and cost effective?

Asked By Kevin Spellman | Feb 23 18
7 Answers

Climate Zone 3C: Crawl space, roof, and wall systems review

I'm in the design phase of a remodel of an existing 2 story house, CZ3 coastal, zip code 95062. The scope includes a new foundation and gutting the house with some interior walls moving, but for the most part keeping the existing exterior shape and roof line. Goal is a high performing house (well insulated, air sealed, mechanically ventilated, high IAQ and minimal heating and cooling loads). I've attached a line drawing of the shell for reference.

Asked By Phil Boutelle | Jan 9 18
1 Answer

Purchasing electricity

Exploring utility options outside the local utility:

Where do you purchase electricity? What is the cheapest commercial/non-solar source?

Thank you.

Asked By Emerson | Feb 23 18
9 Answers

Zehnder HRV/ERV configuration

We got a quote on a HRV/ERV 550 model, we had been trying to decide whether to size down to a 350 or not but I think we're going to stick with the 550 they recommended.

Asked By J M | Feb 23 18
5 Answers

Closed-cell or open-cell foam?

With a wall system that consists of 2"x4" wood framed walls, 1/2" plywood sheathing covered with #15 building paper or house wrap and sided with vinyl or cement board would closed or open cell spray foam provide some level of water resistance during a minor flood? Would the sheathing and studs be able to dry? Would rock wool be a better choice for insulation?

Asked By Anthony Swoope | Feb 23 18
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