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3 Answers

I may need to tear out some insulation

Ok..before I found this site and looked into the proper techniques of insulation I started insulating our basement rim joist/sill plate area because we were working on the house and I was losing tons of heat in this area. I insulated about 30' of the sill plate area with foil backed 3/4" JM insulation doubled up..so 1.5" against the 8x8" sill beam.

Asked By Geoffrey Cook | Nov 30 15
6 Answers

Pros and cons of Grace Ice and Water compared to Tyvek Drainwrap

If applying a WRB under rigid foam insulation, what are the pros and cons of using Grace Ice and Water Shield compared to Tyvek Drainwrap, in terms of protecting the sheathing, serving as an air barrier, difficulty of installation, flashing details, and any other reason you might prefer one product over the other to serve as a WRB? Assuming that the Grace product is more expensive, do you believe that it is worth the additional cost on a 2,000 square foot home in Zone 5?

As always, any advice or opinions are greatly appreciated.

Asked By James Timmerberg | Nov 29 15
0 Answers

New HERS rated home: Issues with Trane XL HVAC heat pump constantly calling for heat

Hello guys. Looking for some advice on our new home . Small custom home completed earlier this year. 2 x 6 walls. Single-story. Designed for energy efficiency from the get-go ...

1792 square footage living space. 9 foot ceilings. 2 x 6 exterior walls framed with California corners and insulated headers and insulated wall leads.

Complete spray foam encapsulation. Spray foam walls. Spray foam roof deck, and crawlspace is insulated with spray foam. Crawlspace is insulated to an R-15, walls R-22, and roofline is considered R-38.

Asked By Wayne | Nov 30 15
6 Answers

Humidity control other than plug in De/humidifier

Hi All,
I was wondering if there are any methods for controlling extreme humidity in the summer and extremely dry conditions in the winter that could be automatically implemented (other than just plugging in a humidifier or a dehumidifier).

I have a ground source heat pump in my 180 yr old stone house (uninsulated, because stone), and the humidity levels are extremely high in central Ontario in the summer (like, slippery floor level humidity) and extremely dry in the winter (furniture crackingly dry).

Asked By Terry Sharpe | Nov 27 15
10 Answers

Previous code for unvented cathederal ceiling insulation

Hey All,

Just curious if anyone knows the previous insulation codes for a low pitched, unvented cathederal ceiling.

My home was built in the 60s and I am finally getting around to insulating and finishing the garage with the above described roof. I know current code is r49 with at least r20 of spray foam for dew point and that's my only option. I just don't see how the rest of my house is all still ok since it was built/insulated way before spray foam existing. Now if I want to just fill the garage bags with roxul or cellulose I hear my roof will mold and collapse.

Asked By Steve Gabrielidi | Nov 25 15
8 Answers

Adding foam board to ceiling rafters?


The rafters in my ceiling are only 2 x 6. Is it acceptable to lay polyiso sheets across the top of the rafters, or should I be concerned about the foam acting as a second vapor barrier? The fiberglass batts have a kraft liner facing the sheet rock.

If the answer to the above is yes, can I place the foam in between the rafters against the sheet rock under the fiberglass batts?


Asked By Donald Mendell | Nov 29 15
3 Answers

Visual dictionary for building terms/glossary?

I know there's a Glossary link in the upper right corner of the GBA website, but is there the equivalent of a visual dictionary for common building components? Ok, I know there are some out there (e.g., visual.merriam-webster.com/house/structure-house/frame.php), but is there a good one online that people have used, and is it possible to include a link to it from GBA? I don't always know the names of the building components (e.g., which part of a window is the stool?), and from other poster's questions I can tell that not everyone knows a rafter from a joist.


Asked By andrew c | Nov 29 15
2 Answers

Masonry block wall: To seal or not to seal?

In preparation to insulating my renovation of a 1970s building's masonry block wall with 2" XPS foam board attached directly to the masonry block, should I paint the interior masonry block wall with a sealer like DRYLOK® Masonry Waterproofer or KILZ 2® LATEX Low VOC?

Right now there is a thin coat of cheap latex paint on the block wall.

Russ :-)

Asked By Russell | Nov 29 15
6 Answers

Where to put the smart vapor retarder?

We are remodeling the second floor of our 1956 Cape in Williamsburg VA, climate zone 4. I need advice about where to incorporate the MemBrain smart vapor retarder in the roof and wall insulation stack up.

Roof stackup: Asphalt shingles- Durabuild synthetic underlayment-1x8 plank roof decking- approximately 1.5 inch airspace (ProVent running soffit to ridge vet)- 3.5 inches of Roxul R15 between the 2x6 rafters- 5.5 inches of Roxul R23 between 2x6 “mooney wall” furring running perpendicular to the rafters- sheetrock.

Asked By Chris | Nov 29 15
2 Answers

Questions about insulating 1947 concrete block home in Florida

We purchased a house in Orlando that we plan using as a rental. It is a one story block home, about 850 square feet. As with most houses built here during that time period it had no insulation with the exception of some blown in cellulose in the attic. We have gutted the house and found that originally there was no furring strips and drywall on the inside of the exterior walls, they have been painted and wall papered a couple of times then someone furred them out and put up wood paneling.

Asked By Nathan Vaughn | Nov 29 15
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