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10 Answers

BTUs to Dollars?

Dear GBA Community;

I am looking to build a pretty good house in New Hampshire (zone 6, 1500 feet elevation.) I've read Matin's heat loss calculation blog (which was extremely helpful, as always!- THANK YOU MARTIN!). I also stumbled across this blog entry which was very helpful: http://www.prettygoodlakehouse.com/2013/11/heat-loss-calculation.html

Asked By Rick Evans | Mar 13 17
6 Answers

Will I be in for a electricity shocker?

Hi everyone,

Based significantly on the guidance from the GBA Website we installed a Fujitsu AGU15RLF, Floor Mount Evaporator and Fujitsu AOU15RLFFH Condenser in our Central Massachusetts 2,200 square foot colonial last week. It is exceeding our expectations one week in with cold and snowy weather.

We bought the house a few months ago and it was heated by electric baseboard we we've moved quickly to take control of the heating bill.

The energy audit identified the insulation as "pretty good" and we had air sealing done the same day.

Asked By Peter Kelly-Joseph | Mar 16 17
10 Answers

How to attach vertical siding with a rain screen?

Is there a ventilated furring strip for vertical wood siding? Or, are there clips available? How does a horizontal furring strip not interfere with air circulation when incorporating a rain screen?

This project is in Climate Zone 3C.

Asked By BILL WOLPERT | Mar 15 17
26 Answers

Affordable R-30 walls with thermally broken T-studs

I have used the following wall system on several additions and recently on a 700 sf cottage.
Pretty simple system for small SIMPLE houses and additions. Maybe too labor intensive for huge,
complex houses. I'm in Climate Zone 5, Colorado Front Range.

Framing is 2x6, 24" OC with taped Zip Panels. No exterior foam. Strips of 1.5" foam are tacked to

Asked By Richard Patterman | Mar 14 17
8 Answers

Adjusted HRV Calculations

Hi all. I have been looking at options for HRV's for a new, super-insulated home under design. While the Zehnder CA350 would be great, I am pretty sure it may be out of the price range (the exchange rate between US and CAN $ is killing us right now). In my hunt for alternate units using the HVI directory (http://www.hvi.org/proddirectory/CPD_Reports/section_3/index.cfm) for ventilation equipment, I'm finding it challenging because from what I've learned, the HVI uses kind of a bad testing method for equipment, which can often inflate the efficiencies of the units.

Asked By Burke Stoller | Mar 12 17
3 Answers

What's the best depth (from the upper surface) for PEX tubing in concrete slab?

Getting ready to do a walkout basement build in far Northern Minnesota. 1140 sq. ft. ICF R-37 walls. I'm going to put put somewhere between 4-6" of foam over crushed surface, vapor barrier, then concrete. Some have posted about a crete-heat type but others have said to raise the PEX into the slab. The concrete guy says he's OK with chairs.

Is there a overall preference out there?

Asked By Steve Lenertz | Mar 16 17
22 Answers

Wall moisture monitoring

I'm diagnosing a tricky moisture issue. Part of the process has involved the use of wall cavity humidity and temperature probes. I have some data and I'd like to "peer review" some of the findings in broad strokes.

First off, this great article got me thinking:


Asked By Rob Simpson | Mar 6 17
3 Answers

Replacing an external beam with an internal beam

I have a living room that used to be 10 ft wide and 30 ft long, a previous owner enclosed the porch making the living room 20 ft x 30 ft, then added another porch. where the old exterior was was they added an interior 28 ft beam (2x12's) supported with 3 columns, on top of the ceiling rafters is a 2x4 wall to the roof rafters. The house was stick built in 1964

Asked By larrylwill | Mar 16 17
3 Answers

Does anyone in the Phoenix, AZ area install supply registers in the floor of the main floor?

I am specifically talking about a house with a walk-out basement.

I'll be building a new house with a walk-out basement in the low desert. I'd like my supply registers to NOT be in the attic. Seems nobody wants to do that.

Do floor registers really not work efficiently in the low desert?

Asked By 447debbie | Mar 15 17
1 Answer

Are Capillary Tubes necessary from 800' to 4000 ' elevation?

Does anyone have any experience shipping Insulated glass units into higher elevations?

New Triple Glazed Argon Gas filled windows are being manufactured in the Northeast and being shipped to the Southwest high desert.The highest elevation the shipper will encounter is 4000-4500' Max.

The weather is very dry most of the year in the high deserts..

Asked By Steven Johnson | Mar 12 17
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