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5 Answers

Basement slab perimeter insulation

I was told that the updated code for Zone 5 required R-10 Foam for 2' around the perimeter of my basement. Local code has not updated to the modern one that states this, but I would like to do this anyway. My question is...does this mean 2' of foam going vertical against the footing, or 2' of foam horizontal butted up against the footing that goes around the inside perimeter of the basement? I am trying to understand what the benefit of just 2' does?

Thanks!

Asked By Nicholas C | May 28 15
6 Answers

Spaceloft my only option?

Needing to get all the R value I can get in a limited space. From the cob webs you can see that this is an old house. Recently installed Cedar shakes with felt underneath over the 2x4 studs or mini rafters...
I think they call this a skip sheathing install of the cedar roof?
So, 3.5" is all we have but we'd like to get to an R50 or thereabouts in our upgrade of this 1925 built home in Climate zone 4C.
Spaceloft seems the only option. With an R10 per inch. It comes in 10 cm thickness, 0.4".

Asked By Jan Verschuren | May 29 15
0 Answers

Insulation and mechanical upgrades

We recently purchased a 1500 square foot colonial outside of Philadelphia. I'd like to triage energy upgrades for this house and establish a long-term, holistic plan. We're in climate zone 4, close to the border with zone 5. It was built in 1984, has a finished basement with 1 inch eps foam on the walls a floating slab. Radon mitigation is underway and they will be sealing the slab-wall gap with polyurethane foam. 1300 square feet are split between two floors, and the remaining living space is behind the attached garage, on a slab foundation.

Asked By Jeffrey S | May 29 15
4 Answers

How to air seal from interior with pine siding?

We just gutted the interior of our ~1950 cape on Long Island (NY). The Bottom layer of siding appears to be Pine 1x in good shape with cedar shingles on top of that. I want to air seal the siding from the interior, what's the best way to do this? I assume caulk, but which type? or could I caulk strips of tyvek into the bays?

Question #2:

Asked By christian routh | May 29 15
4 Answers

Minisplit in tandem with a conventional heat pump?

A friend is getting ready to build a 2800 sq-ft retirement home in the hot and humid south, (Houston). His HVAC contractor is recommending a 5 ton, two stage heat pump. This is ~ the traditional 1 ton / 500 ft2 formula that prevails in this area with the added benefit of the two stage compressor. But 5 tons seems like a lot for a tight house and 2.5 tons is hardly the optimal dehumidifier in the light HVAC seasons. The house will be insulated with closed cell foam in the walls and under the roof deck. It is not what you would call an open floor plan.

Asked By Dean Wiley | May 27 15
6 Answers

Attic ceiling project

OK...read lots, know lots, but have a tough situation: 1924 unvented hot/cold attic, shallow rafters (4"), plank roof deck, asphalt shingles/tar paper and wishing to finish the attic space for office/play area. Previous owner installed very thin layer of foil faced batt against roof deck at least 15 years ago--no thermal impact, but more importantly there has been no moisture issues for the past 43 years (28 him, 15 me). I really don't want to go closed cell spray.

Asked By Chris Haddox | May 29 15
1 Answer

Is it advisable to use nail base insulation panels over a roof insulated with closed cell spray foam?

We are renovating an old railroad station, turning it into a residence and are gearing up to put new roofing on the building. Built in 1888, the building has massive overhangs on all sides and the rafters are mostly 2x6s with 4x6s spaced about 8' apart supported by large brackets. We had planned to use closed-cell spray foam insulation in order to get the maximum r-value in the relatively shallow rafter bays. Also, we want to maximize the available head room in the second floor rooms. The underside of the roof will also be the ceiling with t&g beadboard installed directly to the rafters.

Asked By Jodi Gunderson | May 29 15
20 Answers

Is there a standard factor General Contractors use when calculating their fee to construct?

I am in discussion with a builder to construct my new home in zone 4B. We have engaged the services of an energy modeler to determine how to build the most efficient house within the budget. We are grossly over budget, at the moment. I noted that the GC has build a 16% fee into the budget to build the house. This is on top of all the subs and the contigency. Not wanting to negotiate something I have no background on, I'm wondering if this is a negotiated fee or is there some standard? I understand my builder needs to make a profit but I would love to get 16% return on my investments!

Asked By Scott Schroeder | May 22 15
6 Answers

Recommendation for unvented cathedral ceiling retrofit from outside

I have a 1980's cathedral ceiling section (2x12 raftered) of my home with soft sheathing problems. Hence, I need to remove the sheathing and re-roof. Most recommendation are to spray foam against the sheathing, but this requires an additional interior drywall removal and the interior mess and disturbance I'd prefer to avoid. There are also recommendations for large 6+ inch of rigid foam to the outside of the sheathing, this causes difficulty with the home appearance at the eave and problems with adjacent roof lines that aren't cathedral.

Asked By David koeberlein | May 28 15
2 Answers

Overinsulating or underinsulating?

We have a home built in 1986 in Columbus, Ohio (Zone 5). We are replacing our siding due to hail damage and plan to have the following layers on our home:

Existing:
1. drywall
2. 2x4 walls with unfaced batt fiberglass insulation (R?)
3. polyiso 1/2"? - (old, some gaps, foil faced, says "R3.6" on the face)

New:
4. 3/8" EPS w double foil face (~R1.5) - http://www.thermalbuildingconcepts.com/technical/propertySheet/ps-Physic...
5. Tyvek
6. Cedarmax insulated vinyl siding (R2.4) - http://www.proviaproducts.com/productdetail/vinyl-siding/cedarmax/

Asked By Chad B | May 27 15
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