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9 Answers

Hot water re-circ line & vertical head loss

Hi all,

I’m trying to size a pump for our re-circ line. We have a 1 story house, with a tankless water heater in our attic at one end of the house. Our 2 bathrooms are at the other end of the house.

Asked By Joe G | Sep 30 14
2 Answers

Window & door header insulation options - Zone 5

2x6 stud walls, and the header’s have an inside and outside vertical 2x8, with the 2.5” center is empty. The outside sheathing is 1” polyiso with a foil (no OSB or plywood). I want to fill the headers before the windows are installed this week. Drying is to the inside, so no inside VB, and permeability is important. I was thinking 1.5” R6 Roxul ComfortBoard IS or 2” R8 EPS foam. I tried window/door spray foam, but the 2.5” gap was too large, and the foam just falls out to the floor. Am I overthinking this, and I can just stuff it with pink fiberglass?


Asked By Jeff Conners | Sep 29 14
11 Answers

What is the best detail at a slab on grade pour through to insulate the slab?

Or is it just a weak point that can't be avoided?
I have 2" of rigid insulation under the slab and 1" at the L block.

Asked By David A Flannery | Sep 23 14
2 Answers

Tyroc subfloor

Hi would like opinion on Tyroc subfloor for use in basement and if it is better than some of the others subfloors on the market Thanks

Asked By Brad D | Sep 21 14
3 Answers

How do I fix the high air exchange in my straw-bale home?

Two years ago, I purchsed a straw bale home in Minnesota. When I closed the house was in poor shape and the exterior had to be rebuilt. Our first winter in the house was cool and drafty and we were spending a fair amount on heat. We did as much research as we could, but we have struggled to figure out how to fix and maintain our home.

Asked By Eddy Wilbers | Sep 19 14
1 Answer

Fresh air intake filters


I have the RecoupAerator ERV that I am in the process of getting installed. I have some sheet metal/duct people coming next week to give me estimates on installing the fresh air intake duct that will terminate thru an exterior soffit.

The RecoupAerator comes with MERV 12 filtration material inside, but I am wondering how to filter the air at the entry point into the fresh air intake duct. A simple insect screen there might still let small bugs and such into the the duct work where they will decompose.

Asked By Venkat Y | Sep 20 14
2 Answers

Looking for guidance on how to downsize in a green way

Hello. Am looking for some guidance. My husband and I want to sell our current home and downsize to something smaller and greener. Our budget is pretty limited, though, so we're trying to figure out what the best options may be. We will likely have to pay a fair amount just to get out of our current mortgage, pay closing costs, etc. Then we've been approved for a 150,000 mortgage and with that we could:

a. buy an existing smaller home, close to nature (though those seem very hard to find in our budget)
b. buy land and put up a modular home

Asked By Jen Yost | Sep 19 14
12 Answers

Insulation question for new house build

I’m building a brick bungalow in zone 5, please help critique my insulation. The sheathing is 1” Polyiso (foil faced) wrapped in Typar building wrap. I realize the polyiso should be thicker, but I’m told it’s too late. The walls are up and the windows are purchased.

Attic - R50 loosefill cellulose

Main Floor – R22 CC spray foam in 2x6 wall with no VB, drywall and latex paint
- The other option is R10 CC spray foam with R14 Roxul and no VB.

Rim Joist – R12 CC spray foam and R14 Roxul (thermal barrier required)

Asked By Jeff Conners | Sep 12 14
7 Answers

Low/No-VOC PVA glue and Caulk

Hi there,

Just want to be sure I'm not missing anything ---from the reading I've done, it seems that most PVA woodworking glues are fairly nontoxic...We have specified no or low-VOC products for our remodel, but our contractor is not an expert in this area. They want to use Titebond II. It seems like a safe choice. Does anyone agree or have a better suggestion for a carpenter's (wood) glue -- aiming to have a minimal impact on indoor air quality--very limited off gassing.

Asked By Mindy Munger | Aug 14 14
2 Answers

Improved air sealing brings other challenges

In Kansas 9 Jurisdictions allow an Energy Rating Index analysis as an alternative compliance path for meeting the 2012 IRC chapter 11. Other builders use the HERS index for marketing purposes. Use of air sealing recommendations and increased quality of installation have seen air change rates move down from 5-6 ACH pre-implementation to 3 ACH or less in a growing number of audited homes. Early antidotal results are showing problems with supply only strategies. The 6" pipe to the return is causing summer humidity problems in some cases.

Asked By Bruce Chyka | Sep 10 14
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