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1 Answer

Recommendations for a small bathroom reno

We live in Zone 5 (Ann Arbor) and will be doing a small bathroom renovation in our 1957-built home. Mainly addressing functionality and water management (lousy amateur shower tile from previous owners), but I would welcome advice on expectations or direction we should set with our contractor for insulation, air sealing, and other energy priorities. The bathroom is 7"6"l x 7'w (external wall) x 7"6"h. We are planning for a Panasonic exhaust fan and LED lighting (avoiding cans). We will be replacing most drywall in this bathroom, including ceiling, as we replace the tub and wall tile.

In Energy efficiency and durability | Asked By Phil Ray | Jun 25 15
2 Answers

How to install windows if I build with 2" rigid foam?

Hi. I live in zone 5. I want to build my house not only with 2 x 6 stud walls for extra insulation but also with 2" of rigid foam as that is what the article I read said I would need so I don't have a cold wall.

In Green building techniques | Asked By Ralph S | Jun 24 15
11 Answers

Price shopping Roxul Comfortboard IS in Northern New England, experiences?

Looking for anyone's experience in price shopping Roxul ComfortBoard IS in western Maine. My quote from initial search with my building supply resource was crazy high. Seems like there might be 'pockets' of heavier demand, possibly in Vermont, where bulk pricing might be more palatable. Anyone have experience with similar searches?

In General questions | Asked By kevin freeman | Jun 21 15
17 Answers

EPS vs XPS vs EPS with graphite

Hi all,

First of all, thanks for your time reading this.

I would like an advice from you about thermal insulation of the outer walls of my house. My biggest problem is that path that I walk to get inside my home passes between my home and neighbors' house. This path is wide 110cm. So as you can guess every cm counts :) and I need to find best insulation with smaller with and best price :)

My questions are:

In General questions | Asked By Toso Malerot | Jun 18 15
7 Answers

Can you recommend a Passivhaus or LEED-certified modular builder in the New Jersey area?

I am interested in having a net zero modular home built in the new jersey shore area. I would love a home built to passivhaus standards but would settle for leed or some other ultra efficient modular home builders. I cant seem to locate anyone on the internet. can you point me to a reputable company?

In General questions | Asked By Robert Medoro | Jun 9 15
4 Answers

Supply ventilation - energy use impact

I downloaded BEOpt and EnergyPlus and have been experimenting. Some of the outputs are surprising at first but make sense when I think more deeply, However, I have not been able to make sense of the results I am getting for different ventilation options. I am trying to determine if there is some physics advantage to supply ventilation or whether the results I am getting are modeling errors.

In Mechanicals | Asked By Reid Baldwin | Jun 22 15
5 Answers

Insulating second floor band joists from above

A another question led to discussion of band joist insulation, but I have more specific questions that I think warrant a new topic.

I'd like to insulate the second floor band joist in our 1980's colonial house. We're replace the upstairs floors and I think it makes the most sense to insulate from the inside, upstairs floor (as opposed to from the outside or first floor ceiling).

That leaves two options: dense pack cellulose using the 'grain bag' method from holes cut in the floor, or a foam approach enabled by cutting away the subfloor near the perimeter.

In Green building techniques | Asked By Jeffrey S | Jun 20 15
3 Answers

Where's the smell coming from?

A musty, mildew smell emanates from 2 bedroom closets in the front of our single story 13± year old house every time it rains since we bought it 2 years ago (and before us no doubt)...but nowhere else in the house.

In GBA Pro help | Asked By Sallye Esch | Jun 23 15
1 Answer

Air conditioning vents

Dear Mr. Holladay,

I sent an email to you (see below) and you replied but when I opened your reply it disappeared. Would you be willing to reply again.

Hello Mr. Holladay, - air conditioning vent

My house is located in central Florida. It is a two story house and has additional vents in the hallway and each bedroom. All but one shoots out cold and the other shoots out hot (right in the circulation path to the thermostat).They are and are facing the walls. I was told to by a friend to cover the one that shoots hot air so it doesn't keep the thermostat running.

In General questions | Asked By Tim Spaulding | Jun 23 15
11 Answers

Heat loss calculation and minisplit location questions

I am building a modular energy efficient house in N. Reading, MA. The modular company PBS has a lot of experience building energy efficient homes which is why I am surprised at their heat loss calculations. The house is 3860 sq ft not including the walkout unheated basement. PBS uses the ADA in their building method and the other house details are as follows:

House is oriented northwest-southeast
Paradigm Triple Glazed Windows U-.21 Innie
R-10 under slab
R-20 on front and side concrete basement wall, back and garage are the same as above grade

In Mechanicals | Asked By Arthur Ledoux | Jun 21 15
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