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0 Answers

2 backdrafting appliances & dust, do I need an HRV?

Hello, I have a problem with my house.

1) My house is probably air-tight

2) My water heater backdrafts whenever the bathroom fan is on. It's probably backdrafted every single morning (windows fog up & I feel the warm air at the flue when it kicks on....it only stops once turning off the bathroom fan).

3) Opening specific windows in the basement relieve the backdrafting of the water heater.

4) There was a lot of dust on a return-air duct that was right above the water heater. Another supply duct near the water heater had rust.

Asked By j pritzen | Nov 26 15
3 Answers

Previous code for unvented cathederal ceiling insulation

Hey All,

Just curious if anyone knows the previous insulation codes for a low pitched, unvented cathederal ceiling.

My home was built in the 60s and I am finally getting around to insulating and finishing the garage with the above described roof. I know current code is r49 with at least r20 of spray foam for dew point and that's my only option. I just don't see how the rest of my house is all still ok since it was built/insulated way before spray foam existing. Now if I want to just fill the garage bags with roxul or cellulose I hear my roof will mold and collapse.

Asked By Steve Gabrielidi | Nov 25 15
0 Answers

I am a paid member that cant access product guides?

Now I have been blocked?

Asked By Greg Philliips | Nov 26 15
7 Answers

Solar array positioning in Charleston, SC

Our home builder positioned our solar arrays facing east and southeast, but the angle is pitched east on both. One bank of panels are partially blocked by a large oak tree to the east, the roof of the building to the south, and a 2 level garage which partially obstructs the array (12 in each bank) eastward. The other array is pitched east and catches a glimmer of southern exposure sun, but is partially blocked by other large live oak trees to the south,

Asked By F White | Nov 24 15
2 Answers

How to separate house from garage

Our house will have 5" nail base on the roof with a 3" of oc foam on the underside and the walls will be ZipR over 2 x 6 wall. The garage will attached to the house. My question is do you build a wall in the attic between the garage and living area, then insulate it just like an outside wall? Also I don't want any pull down stairs in the house so what should I do for access to the attic from the garage? I thought about have an exterior door installed in the the previous mentioned wall.

Asked By Eric Chandler | Nov 26 15
3 Answers

Atypical cathedral insulation


I'm in climate zone 5A and trying to determine how to best insulate cathedral ceiling in farm/shop pole-type building with unusual design (picture attached). Building is multi-purpose with large portion un-insulated, but I would like to split loft section in half and use half for insulated workshop. Periodically heating around 60-65 deg at the most (but above freeze level all winter). Code does not apply for this building, but I don't want long term moisture issues.

Asked By Matt | Nov 25 15
1 Answer

Can anyone recommend a high quality direct vent natural gas heater?

We are currently using a vent free heater and find that it is causing health problems. Any recommendations or advice would be appreciated. Thank you.

Asked By Grace | Nov 25 15
6 Answers

Split system location

If I am going to install a mini-split in a very small, well sealed, well-insulated new home that will need airconditioning rarely (maybe never) but heat more often, does it make sense to install the interior unit at floor level instead of ceiling level? Is there generally an option offered by mfgr of low or high mounted units?

Asked By A Lange | Nov 24 15
13 Answers

Ideal load for a multispeed inverter-driven GSHP?

In a planned "Pretty Good House" in Mixed Humid, Northern Climate Zone 4, I intend to use a 45 EER Ground Source Heat Pump with 3 inverters (loop pump, compressor, and fan) with a Cooling Capacity range from 9,000 - 24,000 Btu. I wish to have the lowest Peak Cooling Load, that utilizes the equipment most efficiently, while providing dehumidification and keeps short cycling to a minimum. Approximately what sould that theoretical Peak Cooling load be ?

Asked By Ted | Nov 19 15
3 Answers

Inward solar vapor drive with Zip R Sheathing

I am curious if Zip R sheathing would experience any issue with inward solar vapor drive.

We have an upcoming project that will use Zip R Sheathing (in the polyiso 1 1/2" variety) - and will also have a reservoir cladding - stone on the exterior. There will be a minimum 1/2" gap between the back of the stone and the zip - but it won't be ventilated. Still I was curious if the zip coating and osb might allow vapor to be driven through them only to condense at the outside of the polyiso.

Asked By Patrick Kelly-Decker | Nov 25 15
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