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11 Answers

What's the best way to implement polyiso insulation in an old attic about to be converted to living space?

I'm seeing conflicting reports regarding whether moisture barrier should be used for a finished attic roof, or whether the attic should remain vented. I suspect the answer depends on what is done on the exterior side of the roof sheathing (and I don't plan on touching the outside of the roof myself).

My present plan is to install two 2" layers of polyiso rigid insulation with seams both staggered and sealed, and then probably another layer on the drop ceiling and poy walls.

Asked By TimGNash | May 31 18
3 Answers

What is the best scissor truss venting/ insulating option?

I am using 12" raised heel scissor trusses for a cathedral bedroom. One end wall, other connecting to 8 pitch raised heel truss. With valley connecting trusses and main truss no soffit venting area available. What insulation and venting would be best?

Asked By Joseph Isherwood | Jun 5 18
7 Answers

Opinions on my roof/ceiling assembly


I'm working on designing as small addition to our house and I'm looking for opinions on my design.

I'm trying to thermally break the ceiling from the rafters so have drawn foam above the ceiling joists but below the rafters. We have limited height for the roof before it interferes with 2nd floor windows so I can't add foam above the rafters. We don't want a flat roof either. Also, I'd like to stick with a vented roof (not a hot roof).

I think this is a good solution, what do you think?

Asked By David D | Jun 4 18
6 Answers

Gap between drywall and floor

Hi there, I'm remodeling my home out in Austin, where the insulation was removed to address pest and mold issues. I'm looking to put new drywall up, but I wanted to know if it was possible not to have a gap between the drywall and the floor as my preference is to not use trim on this project. The drywall was mainly removed along the exterior walls, up to the 4' high mark, and sometimes 8' tall sections were taken down.

Asked By homeowner123 | Jun 4 18
7 Answers

Creating ICF / Foxblock-style Footing Using EPS Sheets + Rebar

Greetings everyone -

I am trying to figure out an economical ICF design using 4x8 sheets of EPS rather than expensive manufactured ICFs.

After some hunting, I came across a product called the foothold, but they only make them 20" wide. Could be useful for folks building ICF walls or other alternative methods: http://thefootholdicf.com

Asked By Zane Bridgers | May 30 18
3 Answers

Interior Doors: Solid wood vs MDF vs Molded

Interior doors come in solid wood, which is probably the safest, but also most expensive. Trying to discern which are the most affordable. Does someone have a good internet source for solid wood interior prehung doors whose price competes with either MDF or molded?

Interior Doors also come in MDF and molded. MDF is often suspect due to the off gassing.
Does the concern with MDF apply to interior doors, or just trim that may be cut on site and may not be sealed all four sides?
- If the concern applies to interior doors, are there any brands that are better than others?

Asked By c l | Jun 3 18
4 Answers

PERSIST technique

With this design (Persist) combined with a cathedral ceiling with exposed rafters & exposed bottom roof deck. I don't have spacing of rafters yet but lets say they are spaced at 36" or 48" on center with the exposed rafters being 3"X 8" x 17' in size.

My question is what options do I have for attaching both the insulation & the furring strips on the roof
being rafters are spaced so wide.

A short recap,of progress for those who asked to see this house. Poured last piling on 6/2/2018
THANK GOD that step is finished handled to many 80 pounds bags of concrete by myself. twice.

Asked By user-6976637 | Jun 3 18
3 Answers

Partial basement?

Lost our home to a fire in January. Finalizing plans for our forever home. Plan on ICF. Wife and I were flirting with idea of putting in a partial basement (full basements are very rare around here). I was talking to one of the icf reps and he told me I couldn't. It had to be a full basement or none. I ask him why and he said it had to do with the weight of the walls. I planned on putting the partial basement under the center of the home. I thought as long as the basement walls and the house walls both had their own foundations it would be ok but he said no. Is this correct?

Asked By Mcoxrn | Jun 4 18
1 Answer

Is Ice & Water Shield required on exterior walls?

We live in Louisiana. I was told that if you don't not use ice & water shield on exterior walls then you will damage the walls . Like I said we live in the southeast , Baton Rouge , Louisiana.

Asked By Niko0926 | Jun 4 18
13 Answers

Do generous overhangs need venting or insulation?

Building a 1900 sf house, Berkshires, ma - zone 6. We have an unvented roof assembly - flat roof 2 x12s. Interior to be spray foam, but what about the exterior and carport area? I have attached a some perspective elevations for reference
Lukas Schwartz, Great Barrington MA

Asked By Lukas Schwartz | May 26 18
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