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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
3 Answers

What is the permability of half inch (0.5") XPS?

This is related to my other question: http://www.greenbuildingadvisor.com/community/forum/energy-efficiency-an... but different so I'll create a new question.

I see from this link that less than 1" XPS is above 1 perm: http://www.buildingscience.com/documents/information-sheets/info-312-vap....

In Energy efficiency and durability | Asked By Wesley Manning | Jun 21 15
4 Answers

What is the minimum permeability for drying to the exterior in Zone 6?

Are there guidelines on the minimum permeability you should have in an exterior wall assembly for drying to the outside? For a cold climate, specifically Zone 6 in Halifax. We get a fair amount of rain and I'd imagine it'll depend on that as well?

In Energy efficiency and durability | Asked By Wesley Manning | Jun 21 15
3 Answers

ERV / HRV Details

The more I read both here in discussion forums and in articles, the more I ponder various concepts, and the more perplexed I end up. I'm a homeowner undertaking a gut-renovation on nights/weekends/holidays. I'm trying my best to balance idealism and the realistic necessities of my budget.

~2000 sf house in Southern CT; CCSPF insulation throughout; Hydro-Air HVAC system. I'm pretty well convinced that an ERV is the correct choice.

In Mechanicals | Asked By Matthew Kreuzkamp | Jun 22 15
4 Answers

Is this a good plan for updating our wall layers?

This site has been a HUGE help with putting together our plan for updating our 1986 built home while replacing the roof and siding due to a hail damage claim. We live in Columbus, Ohio (zone 5). We have a gas furnace. Thank you!

Our recently updated plan is described below. We plan to have the install done within the next week or two.

1. Should I be concerned about having multiple vapor barriers on the interior with the addition of foam on the exterior? I've read your articles which express concerns about that because of the need to dry to the interior.

In Energy efficiency and durability | Asked By Chad B | Jun 22 15
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