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10 Answers

Strapping for dense-packed cellulose

Looking for recommendations on the correct strapping spacing (12" or 16") to help prevent bulging with a dense pack cellulose installation on walls. We will be using Insulweb over 8" cavities, 16" on center framing.

In GBA Pro help | Asked By Jessie Pratt | Feb 25 14
5 Answers

Permeance and latex paint

Martin et al.,

I have a question for a "Pro" on this blog. I am looking into different encapsulants or paints to go over lead paint in an older home remodel. The permeance for these latex based encapsulants varies widely.

In GBA Pro help | Asked By Michael Enos | Sep 19 16
15 Answers

Attic insulation

We have just built an addition to our house. It is two floors and a basement. The 1st floor is a kitchen and is open to the existing house. The second floor is a master bedroom and a bath. The only connection with the existing house is a door. There is an attic space above the bedroom/bath. It is an engineered truss roof so the space is not usable. We have sprayed the underside and ends with closed cell foam. to R38 or better. The only penetrations into the roof cavity are 1) the bathroom fan,which vents out of the gable end and 2) a required panel in the closet for access to the roof cavity.

In General questions | Asked By Joe Strauss | Sep 16 16
4 Answers

Insulation for retrofit and thermal bridging questions

Hello all,

First time posting and I am hopeful that I can convey my questions accurately. I recently purchased a 1997 home in NC and found out this summer that our home insulation is horrific. One primary reason is design. We have a two car garage (west facing) with a bonus room overhead which are located on the opposite end of the home from our HVAC units. The left, back, and front wall of the garage are open 2x4 stud unfinished. The garage door is uninsulated. The garage's ceiling and common wall to the living space is finished.

In General questions | Asked By Brian Williams | Sep 19 16
3 Answers

Basement insulation with different slab levels

My proposed basement has 2 levels and I am trying to finalize the details to insulate where the 2 levels meet. I am planning on insulating the perimeter walls from the inside. However, where the floor levels change I am contemplating insulating under and around the footer, and then up the sides of the foundation wall to the top of each slab. The assembly from top down is 4" concrete, vapor barrier (not shown), 4" of EPS type IX, 4" of 1/2" clean stone, undisturbed earth. The footer is 30" wide x 12" and the foundation wall is 12" wide, standard size around here.

In Plans Review | Asked By Jonathan Lawrence | Sep 18 16
4 Answers

My interior fireplace tile chipped over a year ago

My interior fireplace tile chipped over a year ago. Now a powdery efflorescence has eaten away at it. Four tiles are now eaten up, flying off, deteriorating before my eyes. Our 1927 fireplace will flake away in a matter of time. A masonry guy inspected it.

How do I attach a picture in this Q/A?

In General questions | Asked By Gina Allen | Sep 18 16
1 Answer

How to cover exterior insulation?

I'm having a hard time figuring out how to cover the exterior foam insulation on my house. There are only a few spots showing but they show some damage already from falling branches/rain/snow. Quikrete and Tuffcoat aren't available where I live so I was thinking of using surface bonding cement?? Is this the correct option? And do I need to add something to strengthen it?

In General questions | Asked By Jenna Bond | Sep 19 16
13 Answers

Controlling bathroom humidity & wet towels

How do you control bathroom humidity after you've left home or have gone to sleep, A/C is put on setback so it doesn't come on, and you leave your towels to dry by hanging them on the back of the door?

I can't tell during the daytime how bad the humidity gets (since the A/C pops on as we start getting home), but overnight, bathroom humidity shoots up & is consistently in the 60-70% range.

In General questions | Asked By Jeff Watson | Sep 17 16
0 Answers


Editor's note: This post is part of an existing thread. I have moved the post to the thread where it belongs. Here is the link: My interior fireplace tile chipped over a year ago. Note to Gina: Please don't create a new thread every time you want to post a new comment. You should add any new comments to the same thread you created to start this discussion. Thanks.

In General questions | Asked By Gina Allen | Sep 19 16
8 Answers

Vented "over-roof" sheathing

I'm building an unconditioned workshop with a cathedral ceiling (i.e., no attic) under a shed roof.
The planned roof stackup, from inside to outside:

Exposed TJI Rafters @ 24" OC
1/2" plywood sheathing w/ h-clips
fully adhered WRB, continuous with wall WRB
2 layers of 3" of Roxul ComfortBoard (R-24 total)
2x4 purlins parallel to ridge, connected to rafters via long screws (these purlins provide a ventilation channel to prevent ice dams)
Snap Lock metal roof (e.g., https://www.pac-clad.com/metal-roofing/snap-clad/) attached to purlins

In Green building techniques | Asked By Kevin Lynagh | Sep 18 16
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