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13 Answers

DIY air sealing equipment

Other than a blower door, which is impractical for this application, what specifc products do you recommend for a homeowner interested in air sealing? What is the best homeowner-grade thermal imager (if there is one), smoke pencil, etc?

Our moderate retrofit reduced a very leaky, large house from 7330cfm to approx 5000cfm, and I want to keep going.

Thank you.

In General questions | Asked By Emerson | Mar 13 18
26 Answers

Insulate this!

This one-room addition has no foundation. There is insulated in walls (likely R11) and ceiling (likely R19 - certainly no more), but not in the floor. As you can see, outdoor air can simply pass through the open space under the floor. When the flat EPDM roof needs to be replaced in 5-10 years, we will install exterior foam board outside the roof deck. Heating is primarily warmed air from rest of house or propane fireplace. Cooling is AC from rest of house.

I'm considering digging 2' out under the floor, and sealing the underside with foam. What approach would you take?

In Green building techniques | Asked By Emerson | Dec 21 17
3 Answers

What do you reccomend for slab edge insulation protection?

Every detail I have seen shows a protective layer but fails to say what has been used succesfully. I have thought of IRMA insulation but it is pricy and not readily available for the homebuilder. It would seem that something made for that purose should be available at a reasonable cost.

In Energy efficiency and durability | Asked By Bob Bourguignon | Sep 14 10
2 Answers

Thermax over XPS rim joist

I believe the answer is no, but no problem layering foil faced polyiso over XPS in the rim joist, correct?

The XPS was can spray-foamed in, no issue if there is a slight air gap between the layers, correct?

Lastly, should I airseal the thermax perimeter with additional spray foam?

I have leftover 3" thermax and only 2" of XPS in that area so I wager it's a worthwhile application.

Thank you.

In Energy efficiency and durability | Asked By Justin Brown | Mar 16 18
9 Answers

Wide gap between mudsill and foundation

Hi all,

I am in the process of air sealing and insulating the rim joist area in my crawl space. I've already caulked in each of the bays and am about it install XPS and seal around with canned spray foam.

While crawling around I noticed that the mudsill is anywhere between 3/4" to 1 1/4" off of the top of the foundation wall. There are shims spaced out all around, some of which are degrading.

The main section of the house (with a full basement) was built in 1976 and the addition with the crawl space I am in was probably done sometime in the 80s. We moved in about 3 years ago.

In General questions | Asked By user-7039735 | Mar 18 18
5 Answers

Mini Split selection

I know this has been a well documented discussion on here. Yet here I am continuing it. I am close to making the final mini split unit selections for my house. I'm looking for advice on comparing three specific models. Let me know if I should be looking at others?

As background information, I am in Chicago and will be using two 1-Ton units to heat/cool my house + wood burning stove. House will have R 33 walls and R 50 roof. 2,100sf two story.

In Mechanicals | Asked By Seth Holmen | Mar 19 18
11 Answers

Exterior Detail Between Poured Porch/Cold Cellar and Main Floor?

CZ6A, Ottawa ON

Having trouble figuring out how to handle exterior wall details at the front entrance where we have a poured slab over a cold cellar meeting up with the house at the front door. The slab will only be an inch or two below the front door (no distinct step, as flush as possible), but the main floor joists will need to sit on the foundation ledge 8" or so below the slab level.

In Energy efficiency and durability | Asked By Lance Peters | Mar 16 18
17 Answers

ZIP, AdvanTech, OSB, and Plywood.

ZIP, AdvanTech, OSB, and Plywood
What are people’s preferences/experiences when it comes to these products in the two following locations?

Roof Sheathing – Vented attic, with metal standing seam over top. Also what underlayment would you use with each?

Wall Sheathing- Inside to out lay-up is ½” drywall (hopefully fairly airtight) (possibly a membrane required by building inspector), 2”x4” studs, ½”sheathing taped (3M) (air barrier), 2 layers of 3” used fiberglass faced polyiso (6” total) Tyvek (WRB), horizontal ¾” furring strips, vinyl board batten siding.

In Green building techniques | Asked By Dave B | Mar 14 18
0 Answers

Basement subfloor design for northern Indiana zone 5

I am currently investigating options for adding some type of subfloor to my basement to try to make the floor feel warmer when finished. The types of flooring being looked at is carpet, engineered wood, and tile.

The house was built in 2004 and I do not remember any foam being placed under the slab before it was built. I do remember pea gravel.

I did the plastic sheet taped to the floor and did not notice any condensation.

The house uses geothermal heat. The basement does have cold air returns and duct vents.

In General questions | Asked By Brad M. | Mar 20 18
3 Answers

Can Larsen trusses be used for roofs?

My goal is to build a net zero home in a cold climate using the most cost efficient designs, methods and materials as possible. I'm in the design and planning stage at the moment and, to lower my costs, I plan to do as much of the work myself as reasonably possible and I'm hoping to use commonly available building materials whenever it makes sense. I'm currently in favour of using the Larsen truss system for a thick wall of dense packed cellulose but I'm wondering if that can be used for the roof as well. Has anyone seen this done before?

In General questions | Asked By user-7037573 | Mar 20 18
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