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0 Answers

Unvented Wood Roof in Atlanta, GA (Zone 3)?

Hi all, I am building a flat un-vented wood roof in Atlanta, Ga (Zone 3) and I want to make sure I am doing it correctly. The assembly that I have so far is:

-TPO roofing
- 1/4" exterior grade drywall cover board
- 2.5" Tapered insulation
- 4" Rigid tapered Insulation
- Waterproof Coating on osb / or peel and stick waterproof membrane
- 5/8" osb
- 2x10" beams (all at the same height)
- 2" closed cell spray on foam insulation
- 1 layer 5/8" type x Drywall
- Resilient channels
- 1 more layer 5/8" type x drywall

Asked By A Patel | Dec 6 16
7 Answers

Is this a valid way to measure heat load?

Our manual J calculation said that the heat load of the house is about 30K at about 65 degree delta T. (It was more precise than that but I don't have the report handy, so I am going from memory.) I am hoping to confirm that the actual load is not too far away from that before we get into really cold weather.

Asked By Reid Baldwin | Dec 5 16
1 Answer

Can this assembly work for a Flat Unvented Wood Roof in Atlanta, GA (Zone 3)?

Hi all, I am building a flat un-vented wood roof in Atlanta, Ga (Zone 3) and I want to make sure I am doing it correctly.

Asked By A Patel | Dec 6 16
8 Answers

Mini Split Questions

-I'm in zone 4, midwest US, and am about to buy a ductless split system for my main structure and the addition I'm finishing now. I am concerned as three of the five rooms I am putting them in are pretty oversized (~2600k btu load cooling, using the 6k heads) and the rep is saying I should go with the H2i. He said if I never need the low temp operations, the heater was worth the money.

Asked By Mike M | Dec 5 16
1 Answer

Exterior Foam application and window details

Im in Phoenix about 6 months away from starting my build. I was thinking about upgrading my exterior foam from 1.5" to 3" EPS. The window detailing is where my question lies. I've read the articles here, but we will be using mostly EFIS for our exterior cladding (with some stone veneer). My thought was to nail the window to the exterior after the OSB and Tyvek stucco wrap just like you would without using foam. Then add the 3" of EPS right up to the edge of the window and just add the EFIS to the 3" return created. For the stone veneer we will just frame out the window the 3 inches.

Asked By Jeffrey Savage | Dec 6 16
1 Answer

Batt Insulation

I'm in the process of buying a home (Metro New Orleans, Zone 2A, very warm and moist) for my daughter and noticed the attic insulation was installed with the Kraft paper facing up. That problem is being corrected by the seller, but now I wonder if the wall insulation was installed incorrectly as well. When given an opportunity to re-inspect this coming Monday I will be removing electrical covers and other things to see if the insulation problem continues with the outside or exterior walls.

Asked By Bill Stretzinger | Dec 6 16
18 Answers

Another crawl space in the Northwest

Hello all, I have a 1150 sq ft rambler house in Fall City, Washington (near Seattle), zone marine 4c. I am currently in the process of redoing the crawl space. I have pulled the damaged and rodent infested insulation down, and removed the town vapor barrier. It seems I had some rodents that were digging past the foundation and getting into the crawlspace, ruining everything.

Asked By David Meyer | Nov 28 16
12 Answers

Is this a reasonable solar bid? — and other questions

Howdy folks,
I got my first solar bid today, from Consolidated Solar Technologies. For a 3.2 kW ground-mount array in Albuquerque, New Mexico, the total cost before the federal tax credit is $16,300, and $11,410 after the credit. This works out to $3.56/watt.

One thing I worry about is that their calculator shows a higher projected output than PVWatts does. Their tool showed 6,500 kWh yearly, but PVWatts shows 5,844 kWh. This is supposed to be a net-zero-enabling array, so I don't want to underproduce. I'm using 6,500 kWh for my yearly usage

Asked By Nate G | Dec 5 16
14 Answers

How to employ a mixing valve in a closed loop radiant heat system

We are just wrapping up the new roof on my project house and now its [past] time to turn our attention to HVAC - or, more specifically this time of year, Heating! This 1975 house came with radiant heat ceilings as the only source of heat. Recently we have been having night time lows in the teens and daytime highs here in Northern Nevada zone 5 at 5000 feet are usually in the 40's. I have done some preliminary calcs on heat gain/loss, and plan on doing a full Manual J model before laying out any cash for components.

Asked By Roger Smith | Dec 1 16
1 Answer

Rodent-proof soffit vents

Hi,
what is the best way to create a rodent proof soffit vent air intake? I am looking for really durable products. My concern is that rats and squirrels could eventually gnaw through even hardware cloth. Any stainless steal products that people can recommend? Thank you very much.

Asked By Matthias Paustian | Dec 5 16
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