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27 Answers

My husband and I want to build an efficient house

My husband and I want to build an efficient house. The only problem is we are on a very tight budget.

Asked By K Nuss | Oct 11 14
10 Answers

Choose between more/better insulation, or heat pump?...

Last year we had an energy assessment performed in our 1880's home and were recommended several options. We opted to first pursue air sealing in attic with 20" of blown in cellulose. This made quite a difference both in comfort and heating bills.

Our remaining recommendations:

1 - Insulate walls with dense pack blown in cellulose.
2 - Insulate crawlspace (closed cell spray foam).
3 - Replace 4 windows original to house (drafty!!)
4 - Install high efficiency air source heat pump.

Asked By Christian Rodriguez | Oct 9 14
4 Answers

Sizing a minisplit for a 900-square-foot Chicago carriage house

I have a two-level carriage house (900 sq. ft. total). Brick structure, framed in with R-19 insulation, two levels, open loft style.

I'm wondering if the 12000 BTUH Mitsubishi MZ-FE12NA would be enough to heat the space, or should I go with the 18000 BTUH MZ-FE18NA?

Also, is there any reason why I should consider the Fujitsu minisplit too? I've had good experience with the Fujitsus in a warmer climate (than Chicago), but the specs on the Mitsubishi Hyper Heats seem hard to match in a Fujitsu.

Asked By timothy flynn | Oct 15 14
6 Answers

Insulating an attic furnace room

I have a furnace in my attic around which the builder constructed an enclosure from 2X4 and foil-backed fiberglass insulation. I've been told the R-value of the insulation should be sufficient, but there is clearly air getting through at the seams and creating hot spots in the attic which then leads to ice dams etc. What is proper protocol for insulating these attic "furnace rooms"?

Asked By Patrick Finn | Oct 15 14
3 Answers

Vapor barrier

So where do you apply the termite treatment when placing on com. site?

It only make sense to get your sub grade, apply your termite treatment, then your vapor, then your gab, then your steel/wire, then your concrete.

Anything else would put your vapor at risk of being damaged, right?

That's with 4 inch and 4 inch concrete.

Asked By mike brackett | Oct 15 14
1 Answer

Thoughts of REMOTE style building in eastern Canada

Dreaming of building a home aprox. 26x30 two story facing towards south with two large triple glaze casement windows (5'x5') per floor, my thoughts are to use REMOTE on a slab with 4" of exterior foam (eps) and blow in or roxul with in the stud cavities (2x6). The main reason, I am wishing to use REMOTE is for airtightness, plus the thoughts of having less wetting on the sheathing. Am I barking up the wrong tree? The home with be built in Charlottetown, PE.
I know this is very basic info, wishing to heat with minisplit.
Thanks Marty

Asked By marty nichol | Oct 15 14
5 Answers

Islandable battery bank box venting options

Anyone out there have experience with battery bank ventilation in a tight house?

We're building a PGH in Climate Zone 4A. It's designed for net-zero, so we'll have a 6 kW grid-tied PV system. It will also have islanding capability (provided by a dedicated inverter and 12 kVA battery bank).

Based on a rough blower door test we are < 0.6 ACH50.

The battery bank will sit in the basement, which is conditioned space. I want to make sure we are venting the battery box in a safe and effective manner. As I see the issue:

It must vent hydrogen gas effectively
It must not backdraft

Asked By Daniel Ernst | Oct 12 14
13 Answers

Space and water heating for a micro-load house

I've been re-reading Martin Holladay's posts on water heating as I once again deal with a small-ish super-efficient house: 1900 ft2 with a heating load of less than 20 kBtu/hour. The homeowners have access to propane and electricity and here in MN, electricity is still generated by a lot of coal, although the homeowners are planning for a pv system.

At the moment I've narrowed heat/hot water system ideas down to three:
1. use a 6kW modulating electric boiler for space heat (hydronic radiant) and also to fire to an indirect tank for hot water. Also, use a drainwater heat recovery device.

Asked By Rachel Wagner | May 14 13
7 Answers

Does this plan for a vented over-roof make sense?

Hi all, first time asking a question but I’ve found this Q&A very helpful in the past. Thanks in advance for your help.

I’m planning to add a vented over-roof to my zone 6 northern NY house. It has three roof sections: two cathedral and one with an attic. I’ll be dense packing the cathedral ceilings with cellulose and spray foaming the attic before over-roofing, making all three roofs hot and roughly R-25+ before the over-roof. Here’s the thinking on the vented over-roof layers, from bottom up:

1) Decking
2) Air barrier membrane

Asked By Jan Wellford | Oct 3 14
10 Answers

Sleeping coves betters than medium sized bedrooms?

I redesign old homes and rent them out. I found hallways are your worse enemies in use of space. It was not until this last year that I noticed hallways in my rentals that I didn't mean to make.

Lets take a bed of roughly five foot by seven foot for example. If I put this bed in the middle of the room with the headboard on a wall and put three feet around the bed I get a 11 foot by 10 foot bedroom. A typical bedroom size plus or minus. In this typical bedroom I have a roughly five foot by two foot closet.

Current Rental / Bedroom / Square Footage

Asked By S E | Oct 13 14
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