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1 Answer

Can I leave the fiberglass insulation in place and add 1/2 Rmax to the interior

I am starting a renovation in a home with T-111 exterior siding, 2x4 walls, 3 1/2" fiberglass batts for insulation. Can I add 1/2" foil faced Rmax on the interior wall and then sheetrock? Is there a better way to increase the insulation/air sealing then what I 'm describing?

Asked By james DeSalvo | Nov 30 15
0 Answers

ComfortTherm plastic-enclosed batting above radon retarder sheathing in crawlspace?

I have encapsulated my crawlspace (5-7' tall walls) with proper poly I got from radon mitigation specialist. Everything all the way to band joist is encapsulated. I also have good above code level ventilation going between crawlspace and basement. Basement walls I was able to cover in polyiso, but I don't have large enough access hole to the crawlspace to get even 1/4 size sheets of polysio.

Would attaching ComfortTherm plastic-enclosed batting work in that kind of situation? I am in Zone 5.

Asked By Apollo S | Nov 30 15
1 Answer

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
0 Answers

New house question

After a lifetime in the Southwest, we are building our first home in a Zone 6 area (Northwest Montana near the Canadian Border). I stumbled across this website accidentally, and have read everything I can regarding insulation/ barrier techniques, but was hoping for some clarification.

Asked By Bill C | Nov 30 15
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
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
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