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22 Answers

PV, hot water & radiant heating system

Climate Zone: 3c

I recently finished a renovation and added some radiant flooring (about 1800sq/ft,). I'm considering my options on how best to proceed with an energy efficient system for both hot water and heating. I currently only have an old propane water heater, so I'm not married to anything. I'm looking to adding PV to my house, so that is an option to providing heating/hot water.

In General questions | Asked By Mark Hug | Jul 5 16
3 Answers

Waterproofing (Blueskin) applied over tar?

Our contractor has mistakenly applied roll-on tar (damp proofing) to our new residential build as opposed to waterproofing.
we are now looking for ways to further enhance the water/damp proofing and just wondering what your thoughts would be of applying the BlueSkin WP200 stick on membrane over the applied tar.
My concerns would be if the Blueskin would adhere properly and if there would be any chemical reaction between the two that would actually hinder the water/damproofing ability of either or both (tar and Blueskin).

In General questions | Asked By Rick Manitou | Sep 10 16
1 Answer

How to stop condensation on attic air conditioning duct?

One of the A/C ducts in my attic is sweating sometimes, especially when the A/C is running for a while at a time. Its hard to get to, being in a crawl space. The result is formation of brown spots in the ceiling drywall. I was thinking of installing a attire fan nearby, until I read your List of useless devices! on his web page.

In General questions | Asked By Hassan Ahmed | Sep 10 16
5 Answers

HVAC in high-efficiency homes under heavy load

In planning for our upcoming high efficiency home remodel, I had a concern about our HVAC system when under temporary heavy load. I am in the chicago area. Last weekend our neighbor who owns a brand new well-constructed (though not necc highly efficient) home had a party on a hot humid day. The doors were often open as people were coming and going. There were about 10 people in the kitchen/great room area over a couple of hours. Initially, they left the AC off due to the open doors but it quickly became uncomfortable so they turned the AC on.

In Mechanicals | Asked By Alok Khuntia | Sep 9 16
2 Answers

Flat roof roofing, mid-coast Maine

New construction small 8 x 20 attached shed needs roofing. Parameters are: Owner/ skilled carpenter installable. Pitch of roof is 1/2 /12.
I have seen this type of roofing installed; it resembles ice shield, and installer stated it worked on flat roof.
Can anyone help?
Thanks, Potter

In General questions | Asked By Potter Shaw | Sep 10 16
5 Answers

Placing poly on concrete wall and slab

So I am building a new home zone 5 philadelphia area , construction started foundation wall are poured ,

basement and foundation are about 60% below grade 40 % above grade
at present placed 2" xps around whole foundation question is about insulation and placing poly on inside

I was reading article on GBA air seal mudsill assembly

in it they use EPDM gasket as part of mud sill assembly plus poly plus Acoustical sealant
1)is that still recommended way to go ?

In General questions | Asked By Boris Rubinstein | Sep 9 16
6 Answers

Insulating a steel beam

Martin - have you written an article on insulating a steel beam resting on a foundation wall or does anyone have a detail handy?

I am insulating the foundation wall from the inside and I want to create a thermal break under the beam. I know Dow has a insulated column bearing block product, but they make no mention of using it under beams.

In Green building techniques | Asked By Jonathan Lawrence | Sep 9 16
1 Answer

Flooring and a new slab on grade

I have a few questions about installing flooring on a good, new slab on grade. The planned slab construction is 6" of washed crushed stone with drainage pipe, 4" of EPS, 10 mil poly, and then 4" of concrete. The slab is for a planned house near Rochester NY, zone 5A, at the top of a small hill in a field of silty loam. The drainage is naturally away from the homesite, and will be further improved as necessary.

In Green building techniques | Asked By John Ranson | Sep 10 16
5 Answers

Remodeling... Wall detail and stone facade issue

I am in zone 5 (central Ohio). House is single story over basement on one side, two story over crawl in middle and garage on slab opposite side. Current wall is: sheetrock, poly sheeting, 2x4 w/ batt in cavity, T1-11. Front of house is the same but instead of T1-11 its 1/2" fiber board with stone facade on the first floor. Roof is shallow pitch with 24" eaves. The siding is in really bad shape and the poly is a typical 1960s application aka anything but air tight.

My original thought is to go with:

Roxul batt insulation in cavity
1/2" OSB
DB+ or equivalent smart barrier

In Green building techniques | Asked By Scott N | Sep 9 16
3 Answers

Vented flat roof

I'm trying to find the best way to insulate my vented flat roof. I'm in Wisconsin, zone 6b. I've demoed my living room down to the studs. I'm planning to replace the roof in the next 5 or so years, with a non vented roof with insulation on the top of the roof decking. However, in the mean time, I'm trying to come up with a cost effective solution.

In GBA Pro help | Asked By Betina Chaon | Sep 9 16
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