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2 Answers

How to insulate a workshop?

Planning on having a 60’ (L) x 30’ (W) x 12’ (H) post and frame (pole building), built in climate zone 5B. The building will be bisected by a 2x6 interior wall so that 36’ x 30’ will be used as an un-insulated garage and the remaining 24’ x 30’ will serve as an insulated and conditioned workshop. The floor will be 4” concrete slab on grade poured after the building is erected. Exterior walls are metal panels mounted to wall girts and the roof is also metal on engineered trusses.

In General questions | Asked By Ken Hodge | Aug 23 16
1 Answer

Ceiling fan efficiency with 25-foot ceiling

We are in the process of building a house with 12' sidewalls and a vaulted ceiling. The ceiling height from the floor will be about 24'. The area below this fan will be 728 sq. ft.

A local salesperson stated that a ceiling fan (in a vaulted application) will not adequately move air even with a 72" down rod. We were going to purchase a 68" diameter fan.

I do not feel the person in the retail position may be giving the correct information. Any assistance would be greatly appreciated.

In General questions | Asked By Jeff Larson | Aug 23 16
7 Answers

Why is my brand new HRV filled with water?

We did a DER in MA recently (complete September 2015). Part of the mechanical system design includes a Zehnder 350 that is designed to run 24/7 on medium flow to have sufficient air exchange. We have really high heat right now and high humidity. I noticed just now that it was making a strange noise. I opened up the cabinet (following the instruction provided) and found the right side (leads to the house air handlers) was full of water. There is a condensate outlet drain on the left but there is no way for water to get from the right to the left.

In Mechanicals | Asked By Erica Downs | Aug 12 16
4 Answers

XPS insulation around HVAC duct

I have a cabinet in my kitchen and one in each bathroom that has toe kick registers. The HVAC air/heat vent comes out at the floor under the cabinet, but not directly to the vent. I do not want to remove the cabinet and have limited acess to it. I am noticing condensation in the sub floor in these areas, I assume because of condensation due to the entire floor under the cabinet being cooled. My idea is to cut strips of xps 1 inch or so insulation to lay on the floor to insulate the floor.

In General questions | Asked By don gilbert | Aug 23 16
12 Answers

What would you do?

Forgive me for the vague title and the long post but I am lost in possibilities... all expensive!

Oh and its complicated because I am forced into a decision NOW that will heat my 850 sq ft house AND be adequate to heat in a year (or two) when I add 1000 sq ft. The math gets fuzzier when I tell you the plan is to add 4 inches of EPS to ALL the exterior walls (including existing) and 6 inches under the NEW basement concrete).

No one here (Canukistan) is able or willing to do a manual J to size a unit for a two fold job...

I live in Kenora Ontario Canada (zone 7);

In General questions | Asked By tim brown | Aug 17 16
3 Answers

Embedded floor joists air sealing

I have a 1960's bungalow in Canada where the 2x10 floor joists have been embedded/cast into the concrete foundation wall. The foundation wall stops about 1" below the floor sheathing.

I have been considering insulating the rim joist area but because of the embedded joists I don't feel this is a very good idea because of the potential for the joist ends to rot in winter. It seems the best option is to leave that area un insulated.

In Energy efficiency and durability | Asked By David Red | Aug 23 16
23 Answers

Basement subfloor retrofit insulation options

We recently renovated our 1897 brick workman’s cottage here in Chicago. We’ve done our best to upgrade the energy efficiency of it including insulation upgrades– although based on some of threads, may have made a few not optimal decisions (closed cell soy foam interior – we’re in an historic district so we cannot make any changes to the exterior.). We’re now seeking to tackle our basement floor, specifically insulate it.

In Energy efficiency and durability | Asked By brandon antoniewicz | Nov 30 10
1 Answer

Flexible, Long Lasting, Sealant

In upper CZ-4, I will be placing Huber Zip R-6 panels ( with 1" of PolyIso on the interior) against 2x6 stud walls and plates. I would like to use a sealant between the PolyIso and the bottom & top plates and around the windows and doors. A Huber rep recommended the use of a Silicone Sealant or a urethane based sealant. An article that I read recently, "Making sense of caulks and sealants" indicates that silicone does not adhere well to wood.

Would you please recommend a sealant that adheres well, remains flexible forever, forms an airtight seal and of course is economical.

In Energy efficiency and durability | Asked By Ted Cummings | Aug 23 16
2 Answers

It is better to spray closed cell insulation on back of roof decking or over the ceiling joists?

New construction with cathedral roof.

In Energy efficiency and durability | Asked By Cynthia Richards | Aug 23 16
1 Answer

Should closed spray foam be used in Cathedral vented roof?

We paid for spray foam, now the builder is saying there's no need to spray as high in the cathedral roof, it would be more efficient to sheet rock near the HVAC and spray foam. After reading articles it says it's best to spray un-vented cathedral roof, which will keep bad heat and air from entering at the surface, therefore the area between the HVAC and cathedral roof is cooler.

In General questions | Asked By Cynthia Richards | Aug 23 16
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