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1 Answer

Passive heat recovery - passive exhaust and supply

Ventive's passive ventilation and passive heat recovery solution

At first I wanted a fresh air intake warming solution for passive inlets that are balancing/supplying a hybrid, exhaust-only situation. I looked for a way to pre-warm the incoming air for free; to off-set the BTU's lost through the exhaust. There are some "warm wall" designs and "snaked" inlet piping designs that act as passive heat exchangers to incoming fresh air.

Asked By flitch plate | Apr 3 14
1 Answer

Air and vapour barrier questions

Wanted to confirm I have correct understanding:

1. It is ok to have 2 or more air barriers in an envelope assembly
2. It is not ok to have 2 or more vapour barriers, in case moisture got into the wall, it would not be able to dry out.
3. A vendor told me that vapour diffusion only occurs 'in a straight line', i.e. perpendicular to wall or roof. If I have a shiplapped layer, the vapour will not follow the serpentine profile to go in or out of the house.

Asked By Jerry Chwang | Apr 2 14
1 Answer

I'd like to install recessed lights in my walk-in closet. Can I use non-IC lights?

There is thermal insulation in the attic. Is it possible to use NON-IC lights and create a border (kind of fake ceiling), if it is possible, what's the mark spacing between this border and the insulation.

Asked By Natalia Lucar | Apr 2 14
2 Answers

Tankless water heater with a geothermal unit?

I am purchasing a house with a geothermal heating and cooling unit already installed, but I would like to make my house more energy efficient. I was thinking about replacing my current water heater with a tankless electric one as my house is not serviced with gas. I am, however, not sure if the two systems would be compatible or if it would even be wise since my Geothermal is run into my hot water heater.

Any advice would be helpful as I am a first time homeowner, and want to be as responsible as possible.

Asked By Marc Sinclair | Apr 2 14
6 Answers

R21 foil insulation?

I admit my surprise when entering GBA this afternoon and being greeted by a banner advertisement for an R21 thin foil reflective film insulation.

I went to the website, but not a lot of technical information there on why the product apparently has such extraordinary performance, as claimed of course.

Asked By Greg Smith | Apr 1 14
5 Answers

Question about ductless minisplit heat pumps


I live in a 1275 sq. ft. Cape Cod in southern New Jersey (zone 4A). My house was built in 1980, is two levels, is somewhat well insulated, has an unconditioned but insulated crawl space, has dual-pane Andersen windows (manufactured in the early 1980s), and it has asbestos shingle siding.

Asked By Chris Poponak | Mar 30 14
1 Answer

How to retrofit the insulation of an existing basement slab?

What is the best way to insulate an existing walk out basement slab? When I bought the house I removed the wall to wall carpet and sanded and stained the slab. It is too cold to live with.

Asked By anne edwards | Mar 27 14
3 Answers

Getting heavy condensation on the inside of the exterior boards.

I'm in a 50s bungalow in southeast michigan that has a walk in closet built into one of the attics. The closet was recently gutted when my wife discovered mold on the drywall on the only exterior wall of the closet. The exterior wall was poorly insulated and I figured that's why it was wet. I left it open for two weeks to dry out, which it did so I installed r-13 faced fiberglass insulation and left it for a week. I pulled back the insulation a week later to find the wall was soaked again.

Asked By Adam Karavas | Mar 23 14
3 Answers

Effect of adding cellulose insulation on top of existing R-19 fibergass batts

My builder has installed R-19 fiberglass insulation (with vapor barrior) in the attic of the 2000 square foot one-story house he is building for me in Maine. He now plans to add 13-14 inches of blown Green Fiber cellulose insulation on top of this. Cellulose insulation being as heavy as it is, my concern is that it will compress the fiberglass, diminishing its loft and hence diminishing its R-value. Does anyone have any data on the relationship between compression and loss of R-value with fiberglass insulation?

Asked By Robert King | Mar 23 14
3 Answers

What is the solution to improperly insulated cottage?

If a 100 year old building was insulated from the inside using bat insulation, then poly vapour barrier,then reinstalled wood panelling (therefore no airspace) how do you resolve? Five years have gone by and the exterior oil paint, overcoated with latex paint is blistering and peeling to bare wood mainly around windows and newer pine clapboard. How can you solve this problem from the exterior? A thought of tyveking the exterior then strapping then adding new siding...would this be good enough?

Asked By Chris Marlin | Mar 23 14
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