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14 Answers

Attic insulation quandary

Seeking advice on renovation plans for a 1910 house in ND - Zone 7.

- 2 1/2 stories above ground with full basement.
- 2nd story has 'sun porch' facing south.
- 2 layers of siding. Inner layer has lead paint (of course)
- Insulated in the 70's with formaldehyde foam, holes drilled through exterior to fill cavities.
- High efficiency propane furnace, forced air.
- 2 chimneys.
- 1st in middle of house used for original oil-burner furnace and water heater. Now used by wood fireplace in basement.

Asked By Tim Lange | May 16 16
12 Answers

Is it possible to repair a SIP roof that is rotting?

We built an SIP home using panels from ACH Foam Technologies. The roof was installed according to manufacturers specks. The panels were OSB on both sides of expanded polystyrene insulation, about 7" thick. Block splines were installed with the prescribed Do All Ply sealant. This design had space between the lines of calk for air to move vertically. The OSB has begun to de-laminate at the seams visibly under the shingles.

Asked By Allan Poole | Sep 6 15
10 Answers

Stamped concrete patio near foundation

Hi all,

I have a couple of questions regarding a patio near the foundation of our house. My wife and I have been dealing with water issues in our basement/crawl space for a while now, and we just recently had a contractor in to seal the vent properly, install a membrane along the foundation wall, and add French drains tied into the downspout.

As the last part of this work, we have removed a surface deck that the old owners installed and are looking to install a stamped concrete patio with the same dimensions (14x30) pitched away from the home. Specifically my questions are:

Asked By Ryan Lambert | Mar 19 16
11 Answers

Basement slab reinforcement

Not really a "green building" question per se, but too much knowledge and too good a response time for me to not ask here.

Asked By Jim Tyler | May 19 16
4 Answers

Adding insulation to stucco wall in Los Angeles area home

I'm retrofitting a home near Pasadena, CA and am beginning to look at options for insulating the currently-uninsulated exterior walls and could use some advice. The home was built in 1963, and the wall assembly appears to just be stucco on lath, then building paper, then studs, then drywall. There's no sheathing and no lateral bracing except for some diagonal 2x4s at the corners. (please see photos)

Asked By Chris Stratton | May 17 16
2 Answers

I am giving up in Illinois

For the past 6 months we've been trying to find a qualified contractor who can design and install a Mitsubishi hyper heat system for a 3K sqft gut rehab home.

We are trying very hard to break away from the traditional horse cart technology of a furnace and blower.

It's practically impossible to find someone who works on these new inverter-based systems. First off is the issue with Manual J and Manual S. The city requires this, and I understand that the inverter systems may not fully align with the Manual J/S norm.

Asked By Ismail Mohammed | May 16 16
4 Answers

Sub-slab drainage stone size

I know the typical recommendation is 3/4" no fines. Foundation contractor and stone supplier are recommending I use 1.5". Foundation contractor is trusted and has used product a great deal including under some very dry basements that I've been in. Stone guy says he has 3/4 no fines - but it's more money for no gain. I have seen the product they are calling for; it's a mix of ragged and round stone that would surely drain very well. I can tractor stone in, so will be able to minimize trying to stick a shovel in it. SDR 35 interior footing drains.

Asked By Jim Tyler | May 13 16
1 Answer

Patio roof on top of insulated roof detail?

Zone 4A, hip roof with 4:12 pitch; spray foam insulation to be on the interior side of the roof deck (not ventilated). I will be adjoining a new roof out over a patio, placing the new ridge and rafters on top of the existing zip sheathing . The patio roof will have exposed rafters, and the wall of the house will extend up to the new ridge, so the part behind this vertical wall that joins with the existing roof will create a dead space.

Question: is the dead space between insulated roof deck and addition an issue?

Asked By David McNeely | Apr 29 16
5 Answers

Is this wall assembly okay?

I live in upstate SC in climate zone 3. It would be more like 3.5 if such existed. I'm about to build a house and the wall assembly I want to use is slightly different than examples that I have seen and I'm concerned about drying/dew point.

I plan to use 2x4 wall construction, wrap it with 2" of rigid Roxul abd 1/2" Zip sheathing with a brick veneer. My thinking is I have a standard 6 9/16" window/jamb width but I have also killed the thermal bridging.

Asked By Chip Radford | Apr 26 16
1 Answer

Update on polyiso as a WRB?

Martin did an article on Using Rigid Foam As a Water-Resistive Barrier back in Sep 2010. In it he brought up the possibility that polyiso might shrink over time, so might not be reliable as a WRB even though rated for WRB use. Hoping that 5.5 years later there is enough new information for an update on best practices and practicality of utilizing exterior polyiso as a WRB.


Mitch Costa

Asked By Mitchell Costa | Apr 22 16
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