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2 Answers

Do I need Tyvek?

I'm retrofitting a 1952 ranch stye house in Connecticut. The wall sheathing is 1x6 tongue and groove. I'm going to put two layers of 1 3/8" polyiso on the exterior.

Sheathing is now covered with tar paper. I'm thinking of taking of the tar paper (its damaged on a lot of areas) then install polyiso over the sheathing without any Tyvek - Each sheet of polyiso will be caulked around the perimeter. Interior walls ares stripped and will be dense packed with cellulose.

In Energy efficiency and durability | Asked By Walter Gayeski | Jun 24 12
6 Answers

Ever a good idea to install a powered roof vent?

I know these powered roof vents get a bad rap, but is it ever a good idea to install them?

Such as if the attic floor (ceiling below) has been air sealed. This way the powered roof vent should not be pulling conditioned air from the house, rather it's pulling mainly from the soffits or other areas of easy entry.

Also assuming, the power roof vent is temperature controlled and electric efficient.

Zone 4 represented


In Energy efficiency and durability | Asked By Mark Lancaster | Jun 22 12
5 Answers

Interior basement wall insulation - options after framing has started

So, we decided late in the building process to finish some of the basement. I forgot to specify that rigid foam be applied to the interior basement wall, and the interior framing has already been done. I'm still kicking myself for the oversight. I'm sure the builder is planning to go with 'code' and put in fiberglass insulation in between the studs against the concrete wall.

So...what options do I have at this point to minimize future moisture problems. I can specify paperless drywall. Might be able to get rigid foam cut and applied between the studs.

In Green building techniques | Asked By Bryan Anderson | Jun 22 12
1 Answer

Basement floor detail — 1896 New England renovation

I'm preparing to renovate the basement of an 1896 Cambridge MA residence. The foundation is classic brick on stone. The stone is 2-3 feet at the base. The existing floor is hugely degraded 2" thick concrete poured on soil full of dense clay. It is always moist, though there is little standing water. I would like to remove the old floor and as much soil as I can safely take out so as to build up a new insulated slab as per attached plan.

A few questions:

In Plans Review | Asked By Jason RosenJasonR | Jun 22 12
3 Answers

What's the best kind of damper to install on a kitchen exhaust fan?

Luckily, my clients trust me and declined to order a huge 1600 CFM kitchen exhaust fan, and settled on a 3 stage fan with a maximum of 400 CFM. I'd like to install a damper somewhere, but I'm running into two issues: First, it seems that building code here in NJ does not allow for an inline damper to be installed (I think). I searched for wall termination louver type dampers, but this fan is not powerful enough to open them (they are typically used in commercial or industrial applications).

In Green building techniques | Asked By Armando Domingos | Jun 15 12
3 Answers

Is there a tankless venting equivalent of drainwater waste recovery devices?

I was looking at wastewater heat recovery systems that wrap around the drain pipe. It got me a wondering - if my tankless exhaust gets so hot that I have to buy very special wall thimbles so it won't start my house on fire, why shouldn't one be able to tap into that?

The exhaust is already fan forced and slopes upward - is there still some minimum operating temperature needed for exhaust to function?

In General questions | Asked By Taylor Bryant | Jun 21 12
10 Answers

Should we install a rainscreen in a 10" wall assembly?

We are building a new home in SE Washington state with 10" thick walls and wondered if we need to worry about having a rainscreen behind the James Hardi lap siding. We get 17-20" of rain here annually and have heard conflicting thoughts about whether it is needed in this climate. We just don't want to end up with any moisture in the wall cavity, but are not sure where it would come from. Here are the details of the wall assembly:

Benjamin Obdyke's Hydrogap housewrap or Sto Gaurd's liquid applied WRB over 1/2" plywood.

In Energy efficiency and durability | Asked By Mark Porter | May 24 12
3 Answers

Gut-rehab envelope assembly advice needed

I am a new forum member and have found a lot of useful information on a wide variety of topics. I am looking for advice on a gut rehab of a 1,035-sq-ft single-story duet starting in the August timeframe. Bottom line, we want to make sure we spend our time and money wisely but also spend dollars now for insulation, air sealing, etc. rather than giving the money to the utility company long term.

A few details about the project:
- We are in zone 3B boarding 3C (Livermore, CA).

In Energy efficiency and durability | Asked By Gary Ingram | Jun 21 12
3 Answers

Heat-pump water heater paired with hydronic air handler?

Does anyone have any experience pairing a heat-pump water heater (GE, Rheem) with a hydronic air handler (First Co., Rheem)?

We have a 1956 raised 1,800-sq-ft. home with 3875 cfm50 which we are hoping to reduce to 1568 cfm50 (70% of .35ACH). Ducts are asbestos, so we are getting rid of them and will get leakage to 6% or better with R-8 ducts. R-38 attic & R-19 crawl.

Current Manual J heat loss is 57,000 BTUH. I'd like to cut that at least in half. Mild coastal climate, so no cooling.

In General questions | Asked By Troy Spindler | Jun 21 12
0 Answers

What is the best sealant to use on cinder block when building a waterfall feature?

I am having a pool build at my home. On our last pool, the waterfall feature leaked continuously. I watched some H&GTV and they recommend a barrier to prevent leaks, but they never say what type.

In General questions | Asked By Nicole Shelley | Jun 21 12
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