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2 Answers

Would metal roofing (say Imperial Rib type profile) on decking and horizontal purlins work for venting a roof assembly with sealed fibrous insulation-filled rafter bays?

The main question is whether the air space provided by the metal ribs would provide adequate air flow. If not, how about vertical 2X 'purlins', forming site-built insulation baffles that would be insect screened at both ends?

In Green building techniques | Asked By Michael Roland | Aug 7 14
4 Answers

Vapor retarders for double stud cellulose-filled wall assemblies

Following up on last month's blog about building codes, am I correct that the code allows interior vapor retarding with latex paint on sheet rock? Also, does the vapor permeability of ZIP sheathing prevent inner wall condensation without the use of exterior foam?

In Building Code Questions | Asked By Michael Roland | Aug 7 14
5 Answers

On a 5/12 pitch truss roof, can I use strip decking 16' o.c. running rake to rake?

I am using vented soffitt with baffles and blown-in fiberglass or cellulose. Ridge will be vented with 'Core-vent' type vent.

Forgot to say, using metal roofing.

In General questions | Asked By David Parker | Aug 7 14
1 Answer

I live in a 1350 sq. ft. tightly constucted home in Pinewood Springs, Colorado, at elevation 6,700 ft.

I, one person, live in a 1,350 sq. ft. tightly constructed home in Pinewood Springs, Colorado, at elevation 6,700 ft.

Heat is provided by a wood stove and electric baseboard heat.

Do I really need an HRV or ERV, or are there simple ways to achieve appropriate ventilation?

I have no ductwork except for 2 bathroom fans and range exhaust

Thanks

In Energy efficiency and durability | Asked By stuart cohen | Aug 7 14
1 Answer

Air Krete

Air Krete seems like an incredible product. Everything about it sounds great. R-value of 6. Inert. No VOCs. Fire Resistant.

How many builders, retrofit contractors are using this?

It does not appear to be widely popular but it seems like a dream come true.

What am I missing here?

What's the catch?

In Green products and materials | Asked By Reuven Walder | Aug 7 14
9 Answers

XPS storage

I'm buying recycled 4" XPS to go under the slab for my new house in zone 6 Maine.
It wasn't as easy to find as I had expected, so when I found some, I ordered it. It gets delivered next week, but I probably won't need it for a few weeks or a month. Will it be OK to stack it on some framing lumber on the ground at the building site until I need it? I could throw a tarp over it if needed. I could put it in the barn, but then I'd need to move it again.

I assume a little moisture won't hurt, but I want to be sure.

In Green products and materials | Asked By stephen sheehy | Aug 5 14
18 Answers

Unvented roof assembly remodel -- technical question

Hi,

In Energy efficiency and durability | Asked By R Bouchard | Aug 2 14
2 Answers

I need to find someone in the Saint John, NB, Canada area to help solve a wooden clapboard paint loss problem!

We built a home twenty years ago and used wooden, cedar clapboards on the exterior. The builder didn't strap over the Tyvek and we developed severe wall rot after a number of years. We literally replaced studs and sheathing and then used tar paper and strapped the walls etc., but we still cannot keep paint on any of our three buildings. The top of the barn wall which is outside of the in insulated loft is fine.

In General questions | Asked By Rob NORTHRUP | Aug 7 14
22 Answers

Operable exterior thermal shutters

Hi,

We are building a duplex in Yellowknife, Canada - climate zone 8 (design temp minus 45 - same as Fairbanks).

Our winters are long and dark so some sort of (external) insulated window shutter is a huge energy saving opportunity. Our walls are going to R50, while triple pane windows get about R4.

I'm thinking of using 2-3 inches of Roxul board sandwiched between wood. That could give up to R12.

In Energy efficiency and durability | Asked By Andrew Robinson | Jun 10 14
4 Answers

How can I maximize the R-value of floor insulation in a walk-up attic?

old house with walk up, unfinished attic. some old insulation under floor boards. don't want to lose floor space which is used for storage. taking up floor to air seal around lights, etc. so I am already in the space. can I put rigid foam in between joists before putting floor planks back down. Not much room there for adding cellulose or fiberglass. foam panels have more r-value. attic has vent at ridge and small windows in gable.

In General questions | Asked By Tom O'Brien | Aug 6 14
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