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9 Answers

Attached garage next to building on posts?

Our house has a 22' x 22' addition that was built (not by us) using posts/sonotube footings. No frostwall. It is, what it is, as they say.

We'd like to build an attached garage next to the addition. So far one contractor has said he won't take the job because he fears excavating for the garage foundation will disturb the posts and without additional support for the addition, we'll have a problem.

I presume that if we throw enough money at this, we could arrange for a temporary support of the addition while we do the work. But that's going to add significantly to the price.

In General questions | Asked By John Gold | Apr 19 16
13 Answers

Ever a good idea to install a powered roof vent?

I know these powered roof vents get a bad rap, but is it ever a good idea to install them?

Such as if the attic floor (ceiling below) has been air sealed. This way the powered roof vent should not be pulling conditioned air from the house, rather it's pulling mainly from the soffits or other areas of easy entry.

Also assuming, the power roof vent is temperature controlled and electric efficient.

Zone 4 represented


In Energy efficiency and durability | Asked By Mark Lancaster | Jun 22 12
1 Answer

What are people using for a capillary break between their footer and foundation wall?

I am getting ready to break ground and of course their are a few minor details I am figuring last minute. One is the capillary break for the footer. I am building in a heavy clay soil that will most certainly have water. I am torn between painting on dry-loc extreme which is most likely cheaper but not really designed for the purpose, and corsella dorken's product delta-footing barrier which is more expensive and has to be ordered. Are there any other low cost alternatives that function well?

In Energy efficiency and durability | Asked By Dillon Vautrin | Apr 22 16
4 Answers

Minisplit location

Hi all,
Getting ready to order a Daikin ceiling mounted mini split and have some questions on its location to make sure I am going to be able to get even temperatures throughout the house.I am using the ceiling unit because my wife hates the look of the wall units and am going Daikin due to having a family member being able to get me the unit at cost.

In Mechanicals | Asked By Chris King | Apr 21 16
15 Answers

How far do your innie tilt and turn windows open?

I am finalizing a materials order for a REMOTE wall build with intus tilt and turn windows. Those of you who have installed tilt and turns in the "innie" position: how much of an opening angle have you achieved?

I know that these windows technically have the ability to open a full 180 degrees into the room, but many common installations and trim details seem to stop them at about 90*. I am having some difficulty finding images of installations that allow greater opening angles, and am considering changing plans to an outie install if an opening closer to 180* cannot be accomplished.

In General questions | Asked By Jim Tyler | Apr 14 16
4 Answers

Zip wall R-6 sheathing plus spray foam or batt

So, I have just framed an addition... 2x6 walls, with zip sheathing with attached r6 insulation. I am in zone 3... Just wondering whether to just fill the cavities with batt or go with open cell spray foam... Having the zip wall taped off well, with good window install, how much benefit I would gain by going with spray foam... The costs are really adding up on my project, just hoping that there wouldn't be a huge negative with going with the batts. Your thoughts?

In General questions | Asked By Dean Sandbo | Apr 21 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

In GBA Pro help | Asked By Mitchell Costa | Apr 22 16
4 Answers

To ventilate or not to ventilate?

Greetings all,

I am in the planning process for a new post frame (pole shed) building that will be used primarily as a wood shop. Planning to start construction within the next month.

The building will be insulated (R50 attic floor and R22 walls) and heated in winter - northern boundary of zone 6. When not in use, the building will be kept mid 40's. Warm up to working temps will be air-tight wood stove drawing outside combustion air.

In Energy efficiency and durability | Asked By Greg Smith | Apr 21 16
7 Answers

Is thermal bridging through a solid wood door a big deal?

We are going to be renovating our 1888 home to "pretty good" standards. I wasn't planning on doing anything to the original solid wood front door besides refinishing, squaring up and rehanging (but I'll pay attention to air sealing as much as possible - we are striving for <1.0 ACH). I am not so concerned about the energy losses caused by the thermal bridge but am a little concerned about creating a condition that causes the door to deteriorate (due to moisture or other reasons).

What, if anything, could happen to the door?

In Green building techniques | Asked By Alok Khuntia | Apr 20 16
13 Answers

USA New Wall & Swedish platform framing


I recently came across Greg La Vardera’s website http://blog.lamidesign.com

Although I have read much on energy efficient wall types here, I haven’t noticed any comments on the USA New Wall. I am interested in other peoples opinion on this construction and how it compares to other energy efficient wall types. (I am thinking about the Building Science Corp s list of walls and how they score relative to each other -http://www.buildingscience.com/resources/high-r-value-wall-assemblies )

In General questions | Asked By Mitchell Daniels | Nov 12 13
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