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14 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
5 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
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
9 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
6 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
6 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
3 Answers

Not including the cost of the blower door test itself, I am looking for a ROM materials and labor cost per ft-2 to seal up a conventional 2 x 4 framed house, sheathed, sided, windows, doors, stud bays, lid, etc.....?

If someone that has done it can estimate labor hours to get to 5-7 ACH-@ 50 I can factor my local labor rate. Please include the trail and errors, IR and smoke back and forth, etc. Or if you sealed up some ft-2 home let me know how long it took...

Thanks!

Asked By Terry Lee | Aug 20 14
3 Answers

I am in the process of shopping for window flashing tape and am running in circles about what brand (and type) of flashing tape to purchase. Obviously, price is a consideration, but I do not want to sacrifice quality and longevity.

Asked By Matthew Michaud | Aug 20 14
16 Answers

I'm building a new house, and would love to hear feedback on the insulation plan. It can be found here: http://lazukars.bitbucket.org/house.png

DESIGN GOALS:

- Have a consistent insulation pattern up from the basement and up through the roof. In this case XPS on the exterior and ccSPF on the interior.
- Eliminate thermal bridges wherever possible.
- Double the insulation required by code

CONCERNS WITH THIS DESIGN:

- Foam Sandwich: The current sandwich of XPS on OSB on ccSPF will create OSB rot. The OSB will not be able to dry to the interior.

Asked By Ryan Lazuka | Aug 18 14
6 Answers

I'm helping a homeowner improve his 1974 ranch, zone 5 Ohio. Attic currently has 6" of cellulose, no air sealing. Blower door results were predictably awful. After removing all recessed light fixtures and fully air sealing the attic floor, I'll be adding more cellulose. There are no mechanicals in the attic, except for a plumbing vent and a little wiring.

Question: are there any potential problems in simply blowing in more cellulose? Even up to touching the roof sheathing near the eaves? (It wouldn't take much, in fact, to completely fill the attic, if one was inclined..)

Asked By Andy Chappell-Dick | Aug 20 14
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