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3 Answers

Wall stack for climate zone (4)

I'm going to be building a new house in Tennessee, climate zone (4). The local codes use 2012 IBC but call for the 2009 International Energy Conservation Code.

I have a couple of restrictions due to the builder / community HOA ... these are 2X4 walls and vinyl siding. Also restricted to a 12-4 roof and 1 story house.

Asked By Stephen Cook | Jul 1 16
16 Answers

Rainscreens with Roxul Comfortboard IS?

Hi all.
I am planning out my wall construction for a home in zone 6. Not much rain (15" annually), but plenty of snow in winter (56" annually). Hot (and mostly dry) in summer (80sF to low 100s), cold in winter (mostly lows in the single digits, but sometimes minus teens F). My house will not have much direct sun due to northern exposure and tree shading.

All that said, here is the wall I am considering:
- wall board
- 2x6 fir studs on 16" centers, Roxul Comfortbatt (R23) between the studs
- OSB, taped and sealed for my air barrier
- house wrap for vapor barrier

Asked By Mike B | Mar 20 16
4 Answers

Low temperature heat pumps

Ductless Minisplits are no longer the only answer to efficient heating in relatively cold climates!
There are, finally, air handlers that allow a fully ducted air to air heat pump system for small heat requirements in cold climates! Mitsubshi now offers the MVZ series, 12,000BTU/h,18,0000BTU/h,24,000BTU/h,30,000BTU/h,and 36,000BTU/h ducted air handlers that pair with their MXZ-C hyperheat outdoor units and together offer 80% + of rated heat output at -13degrees f.

Asked By Jerry Liebler | May 7 16
11 Answers

Seeking insulation recommendations

I work with Habitat for Humanity in upstate SC (zone 3 - warm-humid), and we are researching practices to improve the energy efficiency of the houses we build.

We have been insulating the attic ceiling with blown-in fiberglass but are leaning towards insulating the whole building envelope now (cathedral ceilings and sealed crawlspaces).

First, is it cost-effective to put the HVAC unit and ductwork in the conditioned attic rather than the crawlspace?

Second, what type of insulation should we use in the roof?

Asked By Dylan Hillman | Jun 23 16
6 Answers

Insulating above a garage roof

Location: Western NC, zone 4, mixed humid
Elevation 2000 ft
Roof: slope 2:12, standing seam.
Attic: formed with trusses and unvented
House roof insulation: Polyiso nailbase R15 min above the deck, netted BIBs below.

Asked By Jeremy Turner | Jun 30 16
7 Answers

Woodshop super-ventilation: Any reason to air seal / insulate?

I'm building a 900 sqft woodshop outside of Portland, OR (Climate Zone 4c).

Based on Bill Pentz's research, the best way to avoid fine dust-related health problems is to ventilate all sanding/cutting tools to the outside with ~ 1000 CFM of air, which is enough flow to fully change the shop air every 7 minutes.
Recirculating air filters don't cut it for fine dust --- it has to vent outside.

Taking this airflow as a given, is there any reason to:

1) Worry about air-sealing the shop wall envelope? (There will be an open garage door or intake fan providing makeup air.)

Asked By Kevin Lynagh | Jun 30 16
5 Answers

Dense Pack Cellulose - Problems Using Insulweb?

I'm preparing to spray dense pack cellulose between my roof rafters for a cathedral ceiling

The cellulose will be sprayed between the ceiling drywall and the roof sheathing from above, since the roof is being re-done.

Since the existing sheathing has already been removed to rewire and repair, I was looking at using insulweb for the spraying, instead of through holes in the sheathing. Seems to make more sense since it will allow visual inspection of the fill

I have a couple concerns

Asked By Paul Murphy | Jul 1 16
20 Answers

Mini split advice

Climate Zone 5, Oakland County Michigan, building starting in July
2357 sq ft ranch, 2357 sq ft walkout basement.
2x6 walls dense pack cellulose, 3 inches exterior mineral wool
R60 ceiling insulation
Superior wall foundation for backfilled walls
R 7 Windows from Klearwall
Have access to natural gas but prefer to go electric if possible.

Thought I'd try and get your thoughts Dana and others on our Heating and Cooling plan. We just had a Manual J calculation done:

Total heating required including ventilation air: 37,561 Btuh

Asked By Brian W | Jun 22 16
7 Answers

Installing a metal chimney for a wood stove through a spray-foam-insulated cathedral ceiling?

Planning on installing wood stove with pipe exiting near peak of cathedral ceiling with rafter cavity filled with open cell insulation and vent baffle. I understand the needs for space near combustibles but trying to figure how to install pipe to maintain insulation barrier and keep safety in mind.

Asked By Scott Smith | Mar 29 16
7 Answers

How to work with a very deep truss in vaulted ceiling?

Hello dear friends, as you will see in the attached drawing I am looking at about an 8 foot run of 22" deep truss over my living roof before my ceiling flattens out to catch the height of the second story ceiling in the back of the house.

Asked By Barry Reicker | Jun 29 16
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