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7 Answers

Insulation for 1:12 standing seam metal roof

Hello all,
Newbie to GBA but we are interested in building an efficient home. We live on the edge of zones 4 and 5 in Illinois. 100% of the exterior will be EIFS. The plan is for our exterior walls to be 2x6 with cellulose in the cavity and rigid foam over the sheathing.

My question is about how to ventilate our standing seam metal roof (1:12 pitch). Our architect didn't seem to have a good grasp on green building techniques.

My questions to architect:

Asked By Kevin Hoene | Jul 22 15
3 Answers

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
0 Answers

Insulating a wall that is exterior on 2nd floor, interior on 1st.

I hope the topic of this question is understandable. Imagine a floor plan that is a simple 2-story box (ie, 40x40) that has a single-story wing to one side. The common wall between the main structure and the wing will be both an interior (1st floor) and exterior wall (2nd).

Asked By Clay Whitenack | Jul 28 15
3 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
6 Answers

Is a ductless minisplit appropriate for a house with primary wood heat?

Hello,
I am contemplating installing a ductless mini-split heater in our new build house in Southeast Alaska. The climate is of course very wet, with fairly cool summers and fairly mild winters with the occasional cold snap.
We heat primarily with wood. Is a mini-split heater an appropriate choice when the wood stove is expected to do 80% of the work of heating? We want an auxiliary heater that will simply limit how cold the house will get while we are away for a long day or a weekend (to 50 degrees or so), but will not run at all when the wood stove is going.

Asked By Justin Smith | Jul 23 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
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
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