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11 Answers

Hi

I'm new here, and I really appreciate all the great information that has been provided by GBA and its users.

I've been reading a lot about cathedral ceiling insulation, and it seems like it is a fine line between success and disaster when it comes to moisture control. So now I have a few questions myself that I hope someone could help me answer.

Asked By Chris Jensen | Aug 18 14
7 Answers

Hi all,

I would like folks to offer any advice/criticism on the following wall and roof assemblies from a moisture control standpoint as well as any other concerns they might have. In addition I have a few specific questions on HVAC options. I know that many of my concerns have been addressed in various Q&A's but it is the specific circumstances that I am concerned about here.

Asked By Lowell Garner | Aug 20 14
6 Answers

I hate to continue asking what seems to be a different wording of the same question but bare with me. My house is 2x6 exterior walls, 1.5 inch of polyiso rigid fiberglass faced foam outside the sheathing and Tyvek. We are in the 47460 zip.

I would like to know the best way to achieve the tightest wall possible but still allow my sheathing to dry accordingly. 1-2 inches of closed cell in the stud void is something Dana said would be OK, so I am leaning towards that but want to be 100% sure it's OK.

Asked By Anthony Hughes | Aug 20 14
15 Answers

So, My AC system died last spring, and I was prepping to put new windows (impact resistant, low e) in my house... My house is approx 2200 sq.ft in Florida, south of Tampa... Zone 2A

I had a 4 ton system, and knew that would be too big as a replacement, but my HVAC tech replaced it with what was here and said he could tune it... Now my house averages 55%rh or higher... Up into mid 66-67...

Asked By Chris Marriner | Aug 18 14
8 Answers

Hi,
I need some advice...preferably before I cut a bunch of holes in the walls or ceiling and find out that this was a pointless venture.

So the details:

900sq foot one level, mostly open plan, highly insulated and sealed home.
Heating climate...like really... a lot. -40 C is not unheard of for stretches of time. More typical is -20 C

The house is powered completely with PV.

Heat is supplied by radiant slab, a bit of passive solar. I am also putting in a small wood stove in the next few days.

Asked By keith ahlstrom | Aug 21 14
2 Answers

I have been thinking about the benefit of putting XPS/EPS foam under the basement slab, and it has gotten me thinking.

I am building in zone 6, where it is quite hot for a couple of months in the summer, getting up into the 90s, and cold in the winter, getting down to the 10's (Fahrenheit) on and off for a couple of months.

Asked By Stephen Youngquist | Aug 21 14
Answers

This page describes how to build a DIY blower door:

http://www.builditsolar.com/Projects/Conservation/BlowerDoor/BlowerDoor.htm

Basically you use a furnace blower and a cheap magnetic or tube-of-water manometer. You can't finely tune the speed of the blower like a professional blower door, but given the few built-in speeds of the motor, you can generally find a speed that yields close enough to 50Pa that you can extrapolate the CFM50.

Asked By Nick Welch | Aug 21 14
8 Answers

We are doing rigid foam on 4500 sq. ft. of exterior walls at 4" thick and 4500 sq. ft. of roof at 8" thick in a REMOTE application.

We are attempting to find the best value for our exterior foam insulation.

So far the best value ($26 for 2"x4'x8') we could find was NeoPro TK. Seems to be a new product so not a lot of info on this "revolutionary" new material. http://www.permarproducts.com/insulsheathing.html

Our previous first choice was Foamular 250 http://www.foamular.com/foam/products/foamular-250.aspx, until we started getting quotes ($34 for 2"x4'8').

Asked By Eric Burhop | Aug 20 14
11 Answers

All this talk about ductless minisplits is making me dizzy. If a forced air furnace gives a bad atmosphere in a building, doesn't a minisplit per room just give many bad atmospheres?

Dana reminded me on another post that a forced air furnace increases infiltration/exfiltration. Well, why doesn't a minisplit heater or cooler do the same?

Asked By flitch plate | Aug 19 14
15 Answers

I am ready to insulate a new home, and need to make a final decision. I need help.
I have been the recipient of many helpful tips and guidance from thes pages as well as other green forums and it's all kind of coming to a head in our new home build as I attempt to make a decision about the insulation we will use. Here is the specs on my houses wall stack up

LOCATION: 47460 On the line of upper climate zone 4 and lower 5

2x6 exterior walls, 1/2 inch sheathing with tyvek, 1.5" polyiso foam with taped seams, vinyl siding

Asked By Anthony Hughes | Aug 8 14
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