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4 Answers

Rigid foam and drywall directly on top of plaster/brick interior?

Howdy folks,

New here, hope this is the right format and question category!
I recently bought an 1887 brick Victorian in Colorado. Unfortuately it is covered with years of ugly previous retrofits such as aluminum siding, very dirty fiberglass bats and such. It felt very drafty and the sheetrock was done very poorly. I tore out the sheetrock, framing, and fiberglass in one room to reveal original plaster walls covered with wallpaper. I have read extensively on rigid foam retrofits in old houses, but have come to no conclusion on better insulation options.

In General questions | Asked By Trevor Mark | Jan 8 16
2 Answers

Air infiltration through kitchen hood exhaust duct

Hello, I'm sure this has been covered, but I must be searching on the wrong terms. My newly installed Broan 350 cfm hood vent is back drafting exterior air into the house when it's off. Now that it's below zero F, it's also collecting condensation. There is only about an 18 inch run of duct between the inside and outside. Is there anything I can do to help the situation, short of replacing the whole hood?


In General questions | Asked By Ryan Griffin | Jan 9 16
4 Answers

Air Sealing HRV

First off, a little about my situation. I live in Nova Scotia, in an 11 year old split entry, ~1200 sqft per floor with a fully ducted HRV. I had an energy assessment completed a couple of days ago. The results of the blower door test were good, 1.91 ACH and Equivalent Leakage Area 335 cm2. I've started sealing up some obvious air leaks, but one thing that crossed my mind is that the HRV only runs 20 minutes per hour at minimum speed, and only during the day. Well, when we shower there's about 40 minutes of full speed, but that's it.

In Mechanicals | Asked By Calum Wilde | Jan 8 16
6 Answers

Insulated concrete slab compatibility with linoleum or vinyl plank

This is my first post - hopefully it's in the right category.

Our house is ~20 years old. For the last 15 years, I've has wall-to-wall carpeting glued directly to the concrete floor in my basement. No functional problems.

I'm looking to replace the carpeting with something that is durable, stain-resistant, and long lasting. Current front-runners are Marmoleum (linoleum, so "greener") and a FloorScore-certified low-VOC vinyl plank (Karndean).

According to our plans, the concrete floor assembly is:
- unsealed 4" concrete slab (with a smooth but unsealed surface)

In GBA Pro help | Asked By Mark Wilson | Jan 7 16
2 Answers

How to exhaust radon gas from sealed sump basin when shared with sump pump?

My home is a conglomeration of numerous additions built from 1888 (original), 1989 (includes finished basement), and 1994. Except for the 1989 construction, all floors are built over dirt crawl space.

In Mechanicals | Asked By Greg Funk | Jan 8 16
1 Answer

How much should I worry about how bathroom ventilation fan is installed?

I followed your advice and eliminated recessed lights in my new addition in chilly Vermont. But now when I look at pictures of the bathroom ventilation fan unit that my plumber is getting ready to install I see it sticking way up into my non-conditioned attic.

(1) Is it OK to have the unit sticking way up in my ceiling or should I be looking for a different design?
(2) Should I just pile extra cellulose on top of the unit to prevent excessive heat loss?

In Green building techniques | Asked By David Martin | Jan 8 16
15 Answers

Best practices for cutting foam?

What are people doing to cut EPS foam and control the dust and debris generated, considering the toxicity of the fire retardant chemicals in it?

Some argue the fire retardants are OK, because they don't leach out of the foam much. But it seems to me that the environmental release is probably dominated by the dust and debris generated.

In Green building techniques | Asked By Charlie Sullivan | Jul 6 15
11 Answers

Strategies for a seasonal thermal energy storage (STES) cooler

STES = seasonal thermal energy storage.

I need a cold room for storing seedlings and bare root trees for 2-3 months of the year, from roughly the end of April to the middle of June. The temperature needs to be between 0.5 and 3. Humidity needs to be at 90% The cost of a conventional cooler system is unworkable, both because of the machinery, but also that I would need to upgrade my electrical service, as well as upgrade the power distribution line (700 feet) from the transformer to the proposed location.

In Green building techniques | Asked By Sherwood | Dec 9 15
1 Answer

Full crawl space encapsulation versus just a thick vinyl liner

I have a 20 year old house in South Carolina with a crawl space that I've lived in for a little over 3 months. The house currently has a 6 mil vaport barrier that is in pretty bad shape. Since then our area has had record rain and above average temps/humidity. I've checked under the house every few times it has rained and things usually looked ok. Fast forward to last week when we had another round of heavy rain and above normal temps I check under the house and it is absolutely soaked with water dripping from the piers, fiberglass insulation and beams.

In General questions | Asked By Chris Reynolds | Jan 8 16
2 Answers

Solar ITC Question--any CPAs lurking here?

At first read to a layperson (me), it makes perfect sense that pretty much anyone can install a solar PV system and qualify for the ITC (Investment Tax Credit). There's a residential version (we're all fairly familiar with this one, yes?) and a business version (see http://solaroutreach.org/wp-content/uploads/2015/03/CommercialITC_Factsh...

In Energy efficiency and durability | Asked By jonathan nagar | Jan 8 16
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