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2 Answers

Pretty Good House in Iowa

I am planning on building a "pretty good house" in the MidWest (Des Moines). After throwing around ideas on different wall structures (double stud, 2x6 with wet blown cellulose and rigid foam exterior), I'm curious what the prevailing thoughts are on building a 2x4 wall (16" o.c.) with 1/2" exterior plywood sheathing. 2" rigid EPS would go exterior, with WRB being Tyvek, then furring strips and hardi-plank siding.

Asked By Thomas R | Jul 27 15
32 Answers

More confused....open vs. closed spray foam for my climate zone

Hi,

I want to finish off my third floor. My house is in Richmond, VA - Climate Zone 4 - (right in the middle of the zone). House was built in 1993. The attic is walk up and rafter built with 2x8s. Here are some pics of the space:

Asked By Joe Watson | Jul 21 15
9 Answers

We were looking to replace our front door which has 2 flanking sidelights

The door appears original to the house which was built in late 1890s (all glass is single-pane and the door has no weatherstripping). Needless to say, it's very drafty (we use rope caulk to seal gaps and plastic to cover windows in winter).

We've had 3 estimates for the work, all ranging between $3,000-$5,000 bucks. All contractors cite unknown condition of framing, subfloor, etc.

Asked By Christian Rodriguez | Jul 27 15
1 Answer

Insulate ducts in conditioned basement?

I have been air sealing my ducts as best I can with mastic. I now have the first 4 feet or so of supply duct from the furnace sweating pretty good whenever it's on. This is all in the basement, which we use as another family room like area, don't use it as much as the first and second floor, but a fair amount.

In the summer it's freezing with the air conditioning on and the ducts sweat for a few feet, as mentioned.

In the winter, however, it's still a little chilly, certainly not overly warm.

Asked By Jeremy M | Jul 27 15
5 Answers

Insulation for condensation control changes from IRC 2009 to 2012

I'm building a small house in Portland Oregon, climate zone 4C marine (according to 2009 IRC). I have 2x12 rafters with blown cellulose, then a layer of taped plywood sheathing for air barrier, then 3" of XPS followed by another layer of ply and the roofing on top of that. Since the ceilings are vaulted, it's an unvented attic situation, so I'm worried about moisture. I've got R36 in the cellulose and R15 in the XPS.

Asked By Tom Frisch | Jul 26 15
2 Answers

Flogging the half dead vapor barrier horse…

At the risk of being heaped with much deserved abuse I have a yet more vapor barrier questions.

I am in the process of designing my new home and have settled on a double stud wall construction with a load bearing inner shear wall, a sheathed 2x3 framed outer wall and dense cellulose insulation.

Asked By L. M. | Jul 26 15
15 Answers

Proper way to detail bottom edge of rigid foam next to sill plate

I am going to be installing 2" of rigid foam over my OSB sheathing soon and I have two concerns. The current one is what is the most DIY friendly method to protect that bottom edge of foam that is under the siding, but next to the ground near the sill plate? I want to prevent bugs of course, but also keep moisture out too. I see videos of pros using aluminum flashing but they have fancy breaks and coils of it. Is there a DIY alternative? Local supply store would be Menards if there is a certain product to suggest. Thanks.

Asked By Nicholas C | Jul 25 15
4 Answers

How much more efficiently does a ductless mini-split perform below peak demand?

My Manual J load calculation for my the 960 sf house I'm building in central Arizona shows a heating load of 13,535 BTU and a cooling load of 11,860 BTU.

I'm debating between two ductless mini-splits:
Panasonic E12NKUA with inverter: 12,000 BTU Cooling 13,800 BTU Heating, 20 SEER 10.6 HSPF
Panasonic E18NKUA with inverter: 17,100 BTU Cooling 20,400 BTU Heating, 18 SEER 8.5 HSPF

Asked By Jeff Cooper | Jul 27 15
2 Answers

How to better insulate my roof

I have a log home with a high ceiling. It has 2by 12 roof rafters. Which means I have 10inches of insulation. I live in northern NY. I want to know if I put 2inch foam panels and a metal roof will it increase my r rating? I seem to lose a lot of heat through the ceiling and it's very hot in the summer.

Asked By Rodney Coryer | Jul 26 15
2 Answers

Flat roof insulation

Here is the Chicago area.
If I can't ventilate the flat roof, then what happens?
what if I am using the fiber insulation and radiant barrier together..?

Asked By Mansig Yoon | Jul 26 15
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