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4 Answers

Vinyl siding over rigid insulation

I have a multi family project that needs to be resided. Unfortunately we cannot afford to use cement board siding and are using vinyl. Is it possible to attach vinyl directly over rigid anchoring to the sheathing? It doesn't seem to be an acceptable attachment method from the vinyl siding manufacturers. Is it worth installing sheathing over the rigid, perhaps a taped zip system? Thanks.

In GBA Pro help | Asked By Julie | Nov 25 15
7 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.

In GBA Pro help | Asked By Apollo S | Nov 30 15
21 Answers

ZIP R-Sheathing Climate Zone 5?

I am considering ZIP R-sheathing for a home in Climate Zone 5. The wall assembly would be a ventilated rainscreen as follows (exterior to interior)

1. Hardie Panel siding
2. 3/4" furring/airspace
3. ZIP 1.5" R-sheathing (R6.6 total, 12-16 perms for the OSB, <1.0 perm for the polyiso)
4. 2x6 studs
5. Icynene Low Density (5.5" thick R-20, 11 perms)
6. 1/2" gypsum

In GBA Pro help | Asked By Joseph Yount | May 12 15
1 Answer

Do I require a fresh air intake for my fan coil (forced air system)?

I have a Bosch in slab heating system in the basement and the upstairs is heated with a fancoil. Heat is derived from my domestic hot water system which is also heated by the Bosch Boiler. Why would I need, or do I, nedd fresh air to the fan coil?

In Mechanicals | Asked By Ron | Dec 1 15
1 Answer

How do I properly venilate the new roof?

Because of the design of my house and roof, I cannot have soffit ventilation installed around the entire perimeter of the roof (only on three sides). I currently have two gable vents on each side of the attic/roof. The house is nearly 50 years old. I am about to have a new roof installed. Should I install ridge vents even though I can completely instlal soffit vents? If I enstall ridge vents, what should I do with the gable? Should I simply continue with something that has worked for nearly 50 years, i.e, two gable vents?

In Energy efficiency and durability | Asked By Rosemarie Annunziata | Dec 2 15
8 Answers

Which adhesive for sub-slab vapor barrier seams?

i plan to use 10 mil sheeting on the ground of my lower level, before insulation, radiant, and a new slab.

what kind of tape should i use to tape the seams in the plastic? any recommendations for taping around posts and plumbing is also greatly appreciated.


In Green products and materials | Asked By Josh | Dec 1 15
1 Answer

Does the underside of fiberglass need to be covered in a flash-and-batt unvented conditioned attic?

I'm renovating my cape cod in Maryland and decided to do an unvented roof assembly since I didn't have good ways of venting the roof valleys and I have ductwork running through the attic, so I wanted a conditioned attic. I should have read the GBA blogs before this project to install rigid foam above the roof sheathing but, in the absence of that wisdom, I'm installing R-15 closed cell spray foam directly to the underside of the roof sheathing and R-30 batts directly under that.

In Green building techniques | Asked By Mark Stewart | Dec 1 15
5 Answers

Safe to dense-pack cellulose into cathedral ceiling bays and polyiso later when re-roofing?

I have very high and steep cathedral roof in my living room and since that addition was built in '78, it isn't exactly built to some great insulation standards. Rafters are 8" deep and currently I have windswept fiberglass there. Have no idea how bad that kills the insulation value, but looking at how fast temps drop in that room gives me sense it isn't good.

In GBA Pro help | Asked By Apollo | Dec 1 15
4 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.

In Energy efficiency and durability | Asked By Bill C | Nov 30 15
3 Answers

Smart MemBrain in Zone 5

As some of you may have followed my other Q&A posts, you may know I have installed the Certainteed brand Smart MemBrain on the interior side of my walls.

I live in Zone 5. My walls are 2x6. Exterior to interior is vinyl siding - Green guard Raindrop 3D wrap - 7/16" OSB - 2x6 studs w/ R-23 mineral wool insulation - smart MemBrain - future 1/2" rock - latex paints.

In Green products and materials | Asked By Nicholas | Dec 1 15
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