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9 Answers

Ceiling insulation for a room addition to my house

I'm planning a room addition, 16 x 16 with a 6/12 gable roof and cathedral ceiling, zone 6. I'm not yet committed to anything specific so would like to run this scenario by folks for advice and opinion. I'm wanting to avoid the 5-6 inches of exterior foam (R-25) that would be needed if I went that route. And, I would like to go unvented. Would the following scenario work?

In Energy efficiency and durability | Asked By Howard Gentler | Jun 16 18
5 Answers

HVAC duct size versus grille size

For proper air being returned to the HVAC unit that is the size of the duct have to correlate to the size of the grille for the return air? So for a 12 inch air filter grille what is the largest size return duct that could be attached to that for proper operation?

I’m getting air pressure coming from the attic through the switches ,outlets ,and around the drop ladder in a different zone than the one with what I believe is undersized return.

Thanks Rich

In Mechanicals | Asked By Richt1022 | Jun 18 18
6 Answers

Exterior vs Interior blinds

I know exterior has superior performance, but can anyone quantify how much? The latest heat wave has me lamenting the fact I didn't go with motorized, exterior blinds for the four east/west windows. Original plan was interior blinds. It's not too late to change plans, though the timeline is getting pretty tight.

Can anyone recommend a place to get these at a reasonable price? I priced them out locally last year, and they were a lot (I think four of them came close to the cost of a ductless minisplit).

In Mechanicals | Asked By Trevor Lambert | Jun 18 18
40 Answers

Brick house insulation

All,
First of all, I wanted to wish everyone Happy and Prosperous New Year!
I would like to ask for an advice regarding a wall cavity composition. I am in Westchester County, 30 miles north of New York City, climate zone 4. I am about to acquire a brick house (tiny brick, maybe 2-3 inches thick). Single wythe, I believe. I think that brick is just decorative and is not load bearing at all. Only cinder blocks in the basement support the floor joists. Second floor ceiling joists are supported by wood framing.

In Green building techniques | Asked By Sebastian Smith | Dec 29 17
6 Answers

Bonus room temperature and humidity

We just moved (CZ4, humid) and have a finished bonus room above our unconditioned garage. The insulation is poor. Heat is electric baseboard. AC is currently none. The room is not in regular use. For example, we did not turn on the heat this winter.

If the room were in use, it would be ideal for a minisplit. But, we rarely use the space. Other than a large tub of DampRid, there is nothing up there to protect the space.

What do we need to do to avoid problems from seasonal temperature swings and/or humidity? Can we simply leave it closed and locked, excepting when we have houseguests?

In General questions | Asked By FrankFulton | Jun 15 18
8 Answers

Room over garage

Hi

Climate zone 4c / Seattle / New construction

We are building a new house which has a studio over the garage deck. The raised subfloor of the studio is built with 2x4 sleepers over garage deck. The subfloor sheathing for the garage deck and studio is Advantech.

How do we detail the void spaces between the sleepers? I am worried about moisture getting in there either through condensation or leaks. Currently, the plan is to fill the voids with XPS and tape the seams. However, I don’t trust this solution to get rid of all air pockets.

In General questions | Asked By Jay Raja | Jun 16 18
3 Answers

Replacing R410a minisplit: Lineset cleaning, pressure testing, and purging

Should I use a cleaner designed for converting from R22 to R410a linesets to clean a lineset that will only replace a R410a mini split?

I am replacing a 7.5 year old Samsung 1 ton unit with a Fijitsu 1 ton unit. These are both single units. They both require 1/4" and 3/8" lines.

I've gotten mixed answers from many HVAC professionals on this question. It seems like the wild west here in Wisconsin on mini-splits (and other HVAC subjects).

In Mechanicals | Asked By Resilient_Kevin | Jun 14 18
1 Answer

Reuse old fiberglass batts?

We are gutting and rehabbing an old house. We are pulling out the old fiberglass insulation from the walls and ceilings, and we have quite a large collection of the batts. Can the insulation be reused?

Some of it is obviously in bad shape, but a lot of it is still fluffy and pink with some discoloration. I know the batts acted as an air filter for the (very) leaky house over the decades, and so they have collected dust and dirt.

How much has that degraded the effectiveness of the insulation? Would it be worth salvaging some of the insulation?

In Energy efficiency and durability | Asked By James Fugate | Jun 18 18
14 Answers

Roof / wall connection showing vent above structural sheathing

I know this has been discussed a thousand times here but each situation is unique and I find that answers seem to vary depending upon the mood of the commentator.

I had previously developed a similar detail as the one shown which had furring strips below the sheathing allowing the vent channel to run below the sheathing but I believe this introduces a whole host of problems not the least of which is an area of loose fabric above my dense packed rafters which overtime could become home to a whole host of critters which might then crawl though it.

In Green building techniques | Asked By Ethan T | Jun 15 18
9 Answers

Has anyone built a south-facing roof on a building that's 45 degrees off?

I have the opportunity to add an attached garage to my house, and I'd like to provide a plaftform for solar PV on the roof (Zone 5, NW Ohio). The existing structure (and the entire town) is oriented 45 degrees off; that is to say, the street runs northeast/southwest. I'd be attaching the garage on the side of the house that faces southeast.

In Plans Review | Asked By Andy Chappell-Dick | Jun 16 18
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