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3 Answers

Another “rigid-foam attached to the underside of rafters” plan

This is new construction with an all hip roof with a very short ridge located in the northern part of zone 3. I’ve ended up with a large cathedral ceiling area which opens to additional living space tucked under the roof resulting in an unvented attic. Is my insulation plan workable? Might I have future water issues? Will my stack-up breathe and dry sufficiently? What issues will the trades find with the plan? is there a better plan?

Asked By Richard | Dec 28 15
2 Answers

A couple of renovation questions regarding my 1960 Cape

Hello all, I was looking up information on housewrap, and stumbled upon this website, what a great find. Anyways, I’m hoping to get some information/advice as the best way to go about doing some renovations this spring/summer on my house

Asked By Khouri Rice | Feb 9 16
6 Answers

Spray foam directly on underside of roof?

I have a conditioned attic, currently insulated with R19 fiberbatts between the rafters. No airsealing, hence I want to remove the fiberbatts and spray 3 inches of closed cell spray foam in before putting the fiberbatts back in place. The attic is unvented, for instance no ridge vent exists. Should I put any membrane or the like on the underside of the roof sheathing before spraying the foam in ? I was thinking that would help with keeping the insulation intact in case the roof needed repair later on?

Asked By matthias paustian | Feb 9 16
7 Answers

Reducing noise transfer between rooms through ducts

In our current house which has all rigid metal ducts, noise transfers easily between rooms through the ductwork. For our new house, I want to make sure that the HRV ductwork does not have the same problem.

Flex is often maligned but it seems as though it could be useful in limited quantities. Based on what I read here, it seems that running a short section from the metal trunk to each room, while making sure the section is straight, pulled tight, and sized for the proper airflow (which probably makes this section upsized from the metal diameter), should not cause a problem.

Asked By Nick Hall | Feb 2 16
4 Answers

Alternatives to SPF to insulate floor

I have a late 50's ranch house with a vented crawlspace in the San Francisco bay area. There are remnants of old cellulose insulation in the vented attic, though very little remains. The rest of the house is pretty much uninsulated. Even though we are in N. California, the weather gets chilly, and predictably my hardwood floors (and stone/tile floors in the kitchen and baths) have been very cold this winter. I am in the process of finding a good contractor to do a whole home energy audit, and come up with solutions (as green as possible) to make the house more comfortable (i.e.

Asked By Zach H | Feb 3 16
1 Answer

Perlite vs. rigid foam insulation

Hello have a question that will probably generate many opinions, i am building a new house zone 5 , was planing on using rigid foam under slab , but some one recommended that i use Perlite in bags instead , says
1) easier to work with
2) easier to pour slab over as you can level things out with sand
3) cost about the same or cheaper then ridged Foam
4) has better R value

Asked By Boris Rubinstein | Feb 8 16
9 Answers

Trying to warm up an uninsulated concrete garage floor

Kenora Ontario Canada P9N0E7
Climate zone 7

Background- I have a 24 x 30 ft garage with 2x6 wood framed walls (R20 fiberglass batts in stud bays) and a raised heel truss attic (8 ft walls) the ceiling has R50 blown fiberglass.
The man door is located on the south wall and the two 7x9 insulated overhead doors are on the north wall...the ridge of the 6/12 pitched roof runs E-W.
The concrete pad is a 4 inch thickened edge slab over 6 inches of compacted stone; the earth is well drained and slopes away rapidly in all directions.
I use 1/2 the building for parking and 1/2 for a shop.

Asked By Tim Brown | Feb 7 16
3 Answers

Wall assembly

I am building a new home in zone 6. I have a question regarding insulation in the window wells. I have 4 inches of xps externally. Of course I do not have insulation inside the window well area. That leaves the header area and a small amount around the window uninsulated. Should I use an internal insulation in the stud bays around this area? One window well is in a bathroom. Should a smart membrane be installed in this area?

Asked By Charles Cloud | Feb 4 16
4 Answers

Insulating a 1890 balloon-frame Chicago house

I have a couple questions about my 1890 balloon-frame house.

It is a wood balloon frame house with 1" thick sheathing boards 8-10-12 inches wide. The original siding is a wood clap siding with a paper under it - later the house was covered in a type of tar paper and wire mesh to add a 1 1/2" cement stucco in a brick pattern (one piece shell) -- to give you an idea of outside make up.

I took off some plaster walls in my office to replace with drywall since they were starting to fall off and while those 2 walls are open I figured I would put some insulation in there before the drywall.

Asked By David Post | Feb 4 16
1 Answer

Moisture accumulating before vapor barrier installed.

I'm in zone 7A and built an attached garage this fall: in slab heat, 2X6 walls, Rex wrap and OSB sheeting. The in floor heat got hooked up and turned on the beginning of January at the same time I began insulating the walls with unfaced fiberglass batts and faced batts in the ceiling.

Before I got poly vapor barrier up on the inside, there was a large amount of moisture (it was frost when it was cold outside) accumulating on the inside of the sheeting behind the batts.

Asked By Neil Knutson | Feb 3 16
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