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5 Answers

Sill gasket

I'm in the process of ordering the mud sill gasket, but have been thrown a curve. We're doing 2x6 framing (zone 5).

I was planning to order the BG65 from Conservation Technology but they're backordered and won't have it in time. They're also almost out of the BG63.

They suggested using either a triple row of BG61 or using their BG32 drywall gasket.

I have also seen a few references here to Denarco's SureSeal or Protecto Wrap Triple Guard.

In Green products and materials | Asked By A W | Dec 2 15
7 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.

In Energy efficiency and durability | Asked By Chris | Nov 29 15
6 Answers

Torn between tankless, hybrid, and power vent water heaters

We are going to be removing the chimney and steam boiler with indirect water heater attached to it. Heating and cooling of the house is covered by air source heat pumps and living room is heated by 98% efficiency natural gas furnace.

So now I have a choice to make to replace the water heating setup between three choices:
1. Power-vent water heater seems to be the cheapest route, but I was hoping to draw air from outside and don't think my plumber knows any with that option
2. Siemens tankless high efficiency unit
3. Go with hybrid heat pump water heater

In Energy efficiency and durability | Asked By Apollo S | Dec 2 15
8 Answers

Insulation and plumbing on new construction in Michigan


We are currently in the process of framing a new construction home in Metro Detroit (Michigan). Our priority lies in building the most "nontoxic" home we can, but also want energy efficiency. I have two questions:

1. What kind of insulation do you recommend? I am worried about the moisture and rodent issues with blown in cellulose, but I am not sure if Airkrete is going to be in budget. Any experience? Any contractor recommendations from anyone in my area?

In Green products and materials | Asked By Carolyn | Dec 2 15
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 1 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
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