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3 Answers

"Flash and batt" question: can I re-use existing batts?

We had a tree fall on our house and damage a section of roof that includes a cathedral ceiling/roof. It was previously insulated with R30 batts (faced) under the rafters followed by drywall (this is in part of our bedroom). We are planning to spray 3" of closed cell foam under the rafters and fill the remaining 6.5" with fiberglass batts. I realize that the R30 batts are designed to fill an 8-9" rafter depth but was wondering if re-using them would significantly compromise their insulation properties vs using new R-19 batts.

Asked By Rob Moore | Aug 17 16
2 Answers

Cardboard insulation baffles have fallen down

Hi Pro Team!

I live in a solar (PV and HW), energy star house, built in 2005, in Washington, DC.

I was in the attic today and noticed that some of my cardboard insulation baffles had fallen over. I'd estimate about 1/3 of them. I don't go into the attic frequently, so they could have fallen over up to a few years ago.

Does this pose a problem?

Any guess on cause? Wind gusts blowing through the soffits knocking them over? Age (cardboard becoming less rigid)?

Thank you!

Asked By Michael Harris | Aug 14 16
4 Answers

Fascia/soffit at held down gable

I'm trying to figure out how to frame the subfascia and soffit returns on a roof with the gable trusses held down 5.5". I don't want to do a wide fascia across the whole building, so right now I am planning a boxed return that steps up at the inside edges of the gable trusses, but I'm not completely sold on this solution. Does anyone have an explanation or images of how you have handled or would handle this detail? I am open to all suggestions. Thanks!

Asked By Jim Tyler | Aug 12 16
3 Answers

Can you use open-cell foam against OSB and provide a 3" air gap behind it?

Building a new construction home in a Mixed humid KY climate. Question is referring to insulating the attic space of a 4/12 pitch roof system with a standard roofline. Is it a good idea, logical or crazy to try to insulate the roofline of our 4/12 roof instead of the back of drywall ceiling deck. Plan is to form a 3" air shute from the vented eave between the 2ft on center rafter trusses all the way to the vented ridge using 7/16 osb or stapled in place insulwebbing fabric, applying 6" of open cell directly against the osb/insulwebbing fabric following the roofline.

Asked By Cody Sturgill | Aug 12 16
1 Answer

Rigid Foam on Flat Roof that Terminates to Mansard

I have a flat / Mansard roof. There is an addition to the back of the house that is the same roof type as the original two roof levels. The add-on roof is leaking. It has 3 leaking skylights that I plan to remove. The sheathing is very spongy. I plan to replace the sheathing and to use 3 layers of 2.5 inch polyiso rigid foam above the sheathing.
I only plan to work on the add-on roof for now. My plan is as follows:
1) remove / replace all old decking and any structural members that are rotten

Asked By KALETA HILLIER | Aug 12 16
6 Answers

Subfloor cavity question: Method in the madness?

Just posted this morning about a bathroom remodel I'm doing. Got some great feedback. Thanks much. Now I've encountered a different problem, and I didn't know if I should tack it on to my previous question or just post separately. I've obviously opted for the latter.

Asked By Doug Waugh | Aug 4 16
15 Answers

Hybrid cut-and-cobble foam board with batts in upstairs bathroom exterior walls?

I have a house in Columbus, Ohio (Zone 5) that was built in the early 70s, and I'm in the throes of a complete upstairs bathroom remodel. I've gutted the space down to studs (even replaced the subfloor), but I've opted to keep the cast iron tub. Well, I'm ready to insulate, but as I read the Q&A exchanges on this site (and several others), I realize that my options are limited. The original insulation schematic included black fiber board sheathing on exterior, unfaced fiberglass batts between 2x4 studs, and a 4mm layer of plastic as a vapor barrier over the whole thing.

Asked By Doug Waugh | Aug 4 16
8 Answers

Can I drain my furnace's condensate line into the sealed sump pit?

Some background:

- Radon remediation system in place in the basement (usual sub-slab depressurization).
- Sump pit covered with plexiglass and sealed.
- Basement slab perimeter has drainage channel that wasn't filled in by the radon folks (I gather not optimal).
- We are planning to replace the 80% efficient furnace in our unconditioned attic with a high efficiency unit since we are planning to condition the attic using a "flash and batt" approach.

Asked By Rob Moore | Aug 9 16
2 Answers

HRV delivering treated air directly to the ASHP air handler air intake which distributes cool or warm air through ducts

Has anyone tried this? The baths and kitchen would have dedicated exhaust fans.
This would in net-zero homes.

Asked By susan cosentini | Aug 7 16
4 Answers

Minisplit ducting options for retrofitting two small adjacent rooms

My home in Zone 2B has an approximately 500 square foot addition that was added to its north side many years ago. Like the rest of the 1950s era house, it is built of concrete block, with single-pane metal windows and (amazing to me) a flat roof where the space above the celing/between the joists is vented rather than insulated. Unlike the rest of the house, it is not served by the central HVAC system.

Asked By Nickolas Van Kleeck | Jul 31 16
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