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11 Answers

I have been reading through many of the very informative blog posts about insulation retrofitting. We have kind of a difficult mess to work with. Our house is one and a half stories and we have previously insulated the sloped part of the roof, both sides of the knee-wall and then over the top of the flat part - above the ceiling. We have a conglomeration of materials because we tried to have foam sprayed between the rafters, both where they are exposed and also up in the cavities where they are not exposed.

In Energy efficiency and durability | Asked By Diane Schneider | Jun 27 11
4 Answers

The plans show a mechanical room in the basement garage under living space in zone 4. The HVAC is direct vented and the water heater is electric. I guess considering that combustion in living space is not a concern, does the furnace and water heater work better in the conditioned space than the garage under living space but considered outside ( colder in winter, hotter in summer?)

In Energy efficiency and durability | Asked By Rick Jenkins | Jun 27 11
9 Answers

I am looking to tile my den floor and before I do that I want to insulate the floor. It is over slab with only about 6-12 inches between the bottom of the floor joists and the slab so I cannot access from under it, but I do know that the batts are sagging. The room tends to be cold, I have already air sealed the rest of the room, and would like to address the floor before I tile. My thought was to tear up the subfloor, put in cleats at the bottom of the joists to support rigid foam boards, seal them with expanding foam, then lay out batt insulation in the caviity.

In General questions | Asked By joe Lajewski | Jun 23 11
3 Answers

As a long time builder (general contractor) building consultant and home inspector (& energy nerd) I love to read Martin Holladay's Musings of an Energy Nerd.
I just read through his blog post of Sept. 25, 2009 about the 10 most useless energy-related products. I am wondering if there have ever been any studies done on the hydronic baseboard heaters sold by Hydrosil?

In Energy efficiency and durability | Asked By Brent Lerwill | Jun 27 11
2 Answers

Best air tight electrical boxes--

What are your experiences?


In General questions | Asked By John Nooncaster | Jun 26 11
5 Answers

I find the construction details at this website to be very interesting....

any comments?

In Energy efficiency and durability | Asked By John Brooks | Jun 25 11
6 Answers

One of the conclusions of a blower door test was to insulate the rim joist with spray foam. Unfortunately there is a cold air return duct that runs length of one side of the house in the cavity shared with the rim joist.

Is there a way do handle this effectively without adding a new duct? I assume spray foam cannot be added inside this space as is.

Zone 5a

In General questions | Asked By Jeremy Tesch | Jun 24 11
2 Answers

Recently a client asked me to help him solve a problem with noise in his house which he attributes to a deep-well heat pump his neighbor has.He says the noise is a muted pulsing sound that seems to occur at night when the pump is running.There is no noticeable sound outside the house,as it would be if traveling through the air,and I wonder if it is possible that the sound is being transmitted through the ground.There is a good chance there is solid granite that lies under both houses,which are about 150 feet apart.

In Mechanicals | Asked By Brian Carter | Jun 24 11
9 Answers

I'm trying to find out what are recommended materials to use for a vapor barrier over open-cell spray foam in an exterior wall.


In Energy efficiency and durability | Asked By Mark Zachelmayer | Jun 22 11
5 Answers

I was testing a house yesterday and took pressure pan readings at some of the can lights and bath fans, while the blower door was running with the house at -50. One story house, flat ceilings, vented attic. The can lights are older style, had a good deal of air coming in through them, and tested at about 45 pa wrt indoors. The bath fans are newer Panasonic models vented to a gable wall with well-installed flex, and tested at about 10 pa. They didn't have much air coming in, according to my trusty biometric airflow sensor.

In General questions | Asked By David Meiland | May 26 11
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