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8 Answers

Reducing energy further in Michigan home

We got a 2003 2 story home with a walk out basement. Just got a department of energy home energy score of eight out of 10 and it is predicted to use around 33,000 kwhe a year.

The home is in climate zone 5 and seems to be pretty tight ( 4.5 ach) and insulated beyond the code code at that time.

We just did all LEDs and are getting motion sensors next.

The home has a good southern and eastern pitch to get 5 to 8 kW of solar someday but I know there is more efficiency to get out of it.

Asked By Brett Little | Sep 10 16
2 Answers

Everywhere you look in Maine, contractors are installing minisplit heat pumps

I'm concerned that most of the homes in Maine are not insulated properly for a air conditioning, vapor barrier on the inside of the wall. Is the cooling season in Maine so short and the delta t between inside and outside small enough not to be concerned about condensation in the wall cavity? Also I've spoken to several installers that have these in their own homes and say that they use them more for cooling than heating.


Asked By John Doran | Sep 11 16
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.

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).

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.

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.

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

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 ?

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.

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.

Asked By John Ranson | Sep 10 16
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