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8 Answers

Ducted minisplit duct costs

Hello all, I am planning on possibly installing three separate ducted splits in my home.for heating and cooling. The main reason for 2/3 of these being ducted is asthetics (sp?) and to help distribution.

Does it seem reasonable to pay upwards of $4000 just to install and insulate ducts and pull a vacuum on the line sets and open the valves? This seems awfully high to me as the entire home was originally installed with a 5 ton unit for 10k including the unit.

Thanks in advance.

In General questions | Asked By Mike M | Sep 8 16
3 Answers

Masonry on concrete columns - air gap or not?

New construction in zone 7/8.

We have several free standing concrete columns that support deck framing and porch roof framing which will have a full thickness traditional stone veneer installed on them. Should the stone on these columns be installed with brick ties, weep holes, and a 1" +/- air gap, or grouted solid to the concrete?

We also have two concrete retaining walls that will receive the same stone veneer on the exposed side, the side of these walls that contacts the soil will be either damp proofed or water proofed, same question as above, air gap or grouted solid?

In Energy efficiency and durability | Asked By Chris Armstrong | Sep 12 16
12 Answers

I live in Houston in a house with brick walls

Hello. I live in Houston in a house with brick walls. We have a lot of issues with damp brick walls, mold and mildew. We are currently removing the interior walls to reinsulate them.

1. Can i water proof the exterior walls with sealer, prime them and...

Oops I placed all the questions above...
Money is tight...
We can not use the ac due to mold and need to clean the vents and ducts...diy since we can not pay for this.
we do not have carpet or any floor due to water intrusion...doing all the repairs myself

In Green building techniques | Asked By Pat Porras | Sep 12 16
2 Answers

Attic venting

Indianapolis Zone 5a
My own outside weather station reads mid 70% humidity July through October which is 10% higher than Indianapolis historic values.

single story. baffle vents with roll on ridge vent.

Attic is very very hot and musty. Lots of pressure build-up in summer that presses down into the house bringing allergens with it. Some ice dams in places without baffle vents.

Given the hot/humid summers and colder winters, do i leave the attic ventilation alone?

In GBA Pro help | Asked By Edward Kramer | Sep 13 16
19 Answers

With Zip board as sheathing/WRB, any danger Intello Plus behind drywall will act as 2nd vapor retarder?

Our wall assembly will be the following (interior-exterior):

5/8" drywall
Intello Plus vapor retarder
2x6 studs filled with Roxul batts
Zip board sheathing
4" Roxul comfort board (2" + 2")
1x4 battens
1x6 cedar siding

We're shooting for a Passive House level of air-tightness, so is there any risk the Intello and Zip board sheathing could trap moisture in the wall assembly?

In Green building techniques | Asked By Eric Whetzel | Sep 11 16
6 Answers

Better NOT to vent the top of a rainscreen assembly?

My clients have a 1960s house, 30' from the coastal bluff in Mendocino CA. We are currently re-siding the house by using the old T-1-11 as our sheathing, new housewrap, new rainscreen battens (1/2" pressure treated ply 16" o.c.) with Coravent SV3 at the bottom, then 4x8' hardipanel and finish battens and trim.

In Green building techniques | Asked By cynthia sharon | Sep 12 16
37 Answers

Ice damming — Low-slope roof — Resolvable or hopeless?


I own an older home in Ontario Canada that may have been built between the 1920s to 1950s. It originally had knob & tube wiring.

Each winter I have to deal with ice damming along 2 sides of the roof, no where else. The areas in question are a Low-Slope roof (3/12 pitch, east & west side of the ridge) and a Cathedral style roof (8/12 pitch -- inside the home there is a sloping ceiling that is covered by drywall). See a photo of the home: http://imgur.com/sXUzfzG.

In GBA Pro help | Asked By Jake Rabe | Aug 19 16
3 Answers

Would the condensation be explained by the lack of insulation?

We own a 3 unit building in Chicago built in mid 2000s. Last fall we put on a new warm roof with vapor barrier on top of main roof decking but below the new insulation (insulation on outside) but did not insulate rim joist from ceiling below. We noticed strong odor in unit.

We opened the interior walls of 3rd floor in August and noticed condensation on the walls and rim joist. We read your article on insulating rim joist and NOW plan on doing this using closed cell foam.

In Energy efficiency and durability | Asked By Andrew Rothstein | Sep 4 16
7 Answers

Heat loss through crawl space

I'm considering buying an older, brick exterior, home (about 20 years old) that currently has a vented crawl space. The location is Georgetown Ky. I like the layout and the location but it sure needs some "energy conservation" upgrades. Tentatively the first upgrade will be "sealing" the crawl space, with mult-ilayer reinforced poly, after adding r10 foam on the inside of the crawl space's exterior walls. My initial question is; should I cover the dirt floor with insulation (I'm thinking of r10 mineral wool bats).

In Energy efficiency and durability | Asked By Jerry Liebler | Sep 9 16
4 Answers

What do you guys think about Icynene ProSeal Low-VOC Spray Foam?

I was browsing Youtube and found the following two videos on Icynene's Youtube Page:



I think they are talking about the following Icynene product:


In General questions | Asked By Ken Hammer | Sep 11 16
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