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46 Answers

Best way to fix insulation problem in cathedral ceiling? Please help!

I built my chalet about 8 yrs ago and was up in the attic and noticed black water stains (probably mold).
after many days and night researching what was wrong, i believe my issue is insulation and air leakage.
i have called all the insulation and roofing businesses (not many in this area) and each says its the others issue.

this site has been the most informative, but i cant seem to find any article or videos on how to add or change insulation in a cathedral ceiling after construction has been done.

Asked By Aaron H | Jan 31 16
2 Answers

3" and 4" PVC valves that release water but keep air from entering

Need two of these. Can't find them. I have emergency drains that come from my home appliances to daylight. They're allowing too much air infiltration, because they are open at the daylight ends. They are rarely used but necessary if an inside leak develops.

Asked By Andy Nels | Feb 12 16
4 Answers

Duct manifold for a stand-alone ERV

I'm trying to figure out the best way to install my ERV ductwork. I don't have a forced air system, so each supply or exhaust will have it's own duct. I have seen the typical trunk/branch method, but a manifold system seems easier. Does anyone have experience with building a manifold system for mechanical ventilation? I will have three exhaust ports and four fresh air ports. I've looked at the Zehnder systems and they look pretty slick, but I cannot afford the price. I am leaning toward Thermaflex ducts, which are high quality flexible ducts usually used in commercial applications. Thank you!

Asked By Adam Emter | Feb 9 16
0 Answers

All steel building venting for home

We have an all steel building that we are turning into a home. It currently has a steel roof with fiberglass insulation with a vapor barrier on the warm side, there is no space between the insulation and tin other than the rib gaps of the exterior tin (the walls are the same setup as well). We are going to frame it with wood studs and add rock wool insulation in between the purlins (and girts for the walls) then put our ceiling/wall covering up which will create a cathedral ceiling. My question is how do we vent the ceiling with this setup?

Asked By Victoria Victoria | Feb 12 16
37 Answers

To crawlspace or not to crawlspace?

We are a group of four builders in Quebec breaking ground on a new construction this summer. We’ve been arguing over the niggly details for three years as we try to cobble together the most common sense, super-efficient, affordable house possible. As we seem to be proving, the discussions on how to build can go on forever...

Asked By William | Jan 20 16
3 Answers

Do I need to vent soffits in with an unvented roof assembly?

I have large 4 foot exterior soffits. I am spray foaming the inside of the roof, an unvented attic assembly. Do I still need to vent my exterior soffit overhangs? Do I need to worry about the air trapped in that cavity if I do not?

Asked By dean sandbo | Feb 11 16
6 Answers

Roof clips

Our roof will be 12/12 pitch with 2x6 raifters,would it affect much if we changed to 2x8 to fit a little more insulation,also our roof deck is 7/16 osb taped with a 1.5-2 inch polyiso nailbase on top if that,do you think we need roof clips on the first layer of osb or need to change that to 5/8osb?
Thanks

Asked By Quinton Bryant | Feb 11 16
1 Answer

"Green Building" and current (2012) code

Has current code 'caught up' to the point where "green building" today revolves around code compliance, HVAC design and choice of "green" interior materials?

Has "green building" gone mainstream with regards to the building envelope?

Asked By Chris M | Feb 12 16
19 Answers

Mitsubisi Heat Pump- heat and cool

I am building a 1 1/2 story barn/garage 36 X 34 with an open upstair 2nd floor. It will have 2" form in the walls and 3" sprayed form in the ceiling. Cement floor. not too many windows and 2 garage doors.

I don't need it heated like a home but just confortable when I work in the barn. I would like to keep it about 40 degrees in the winter when not in use and will rarely need it cool in the summer. I live in southern CT.

I've been looking at the high efficienty units around 24,000 BTU. I also need to be able to set the temperature low (about 40) when not in use.

Asked By Fred Gabriele | Jan 31 16
15 Answers

Proper crawl space encapsulation and also radon mitigation questions

Hello, I own a 1968 cape cod style home in East Stroudsburg in the Poconos, PA (region 5). It has a full basement with 7' ceilings and concrete floor with probably little to no crushed stone underneath. At some point, there was a ditch cut out along 2 of the walls, with stone and probably a perforated pipe added, and concrete poured back except for a small channel along the block wall. This leads to a sump pit.

Adjacent to one of these 2 walls is a crawl space entrance where an addition was put in.

Asked By Ryan O'Rourke | Jan 26 16
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