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6 Answers

Dense-Pack Cellulose Cathedral Ceiling

My roof (zone 3B) needs insulation, but between Martin's concerns and the inexperience of the contractors in this market, I am conceding that 5" of polyiso foam isn't going to happen. I think that 3.0" nail base (R15) can though (with taped seams). I'd like to get closer to the code minimum of R30 for the assembly. I would rather not tear out the finished interior vaulted ceiling (cedar shingles on battens on felt paper, I know, strange), but the lousy interior air barrier (i.e. the felt paper) concerns me.

In Green building techniques | Asked By Keith Richtman | Aug 14 14
21 Answers

Soundproofing Bedrooms

What's the general consensus for economically soundproofing bedrooms for guests/family comfort during normal daily life? I'm aware of using more than one layer of drywall, and would like to avoid this option.

Any ideas?

Thanks in advance for your advise,

Robert

In General questions | Asked By Robert Car | Oct 15 10
1 Answer

Is there an energy efficiency penalty for an oversized dehumidifier?

If i buy one that is oversized for my basement it will presumably run fewer hours a day at higher wattage, is there any penalty or lower effectiveness on this?
The one i am considering is 1.85L/kWh energy star rated compared to another 1.85L/kWh unit.

In Energy efficiency and durability | Asked By Alan B | May 22 15
22 Answers

Ductless minisplits - Zone 5 - with basement

Hello folks, this is my first post at GBA so bear (beer) with me. My son and I are building a new for my wife and I to live our days out in, two story bungalow style with a full basement under.

Some stats;

Exterior Walls - 2x6 16" on center with 2' XPS on exterior, wet blown cellulose in the bays. 3/4" rain screen furring over foam, cedar lap siding. R19 in the bays + R10 = R29+

Ceiling - 2x10 sealed vault flash (core bond) + batt - R49

Basement Walls 8' (6.5" below grade/ 1.5" above) with 1.5" polyiso + R13 Batt in 2.4 stud wall over foam - R22

Basement Slab - 2" XPS

In Energy efficiency and durability | Asked By Brian Martin | May 16 15
32 Answers

HVAC options?

I need some help with HVAC planning for a duplex I am currently looking to build. It will be located in South West Manitoba aka Zone 7A from looking at the map.

I have a couple of options...
1) Stick built on site. This would give me the option of a slab foundation aka hydronic radiant heat.
2) RTM moved onto crawl space foundation. This would not allow for hydronic radiant unless I attached the lines to the underside of the RTM flooring (not inside a slab).

In Mechanicals | Asked By R Yan | May 12 15
4 Answers

Yet another window question (YAWQ): Pella Impervia feedback?

Hello,

I'm building a house in central Oregon (zone 5). It's a mostly passive solar design, with CMU shell construction that is insulated on the outside (my builder has a patented method to attach insulation to exterior of CMU walls) and this plus a mix of tile and concrete floors means I have a huge amount of thermal mass.

So we're considering using Pella Impervia with their high SHGC "Natural Sun" glazing for five of the main south-facing 42" x 112" windows (Alpen and their better U-value is planned for the other 30+ windows).

In Green products and materials | Asked By D Wadsworth | Jan 28 15
9 Answers

Can I reuse single-pane steel sash windows?

A client would like to restore some window openings that were bricked-over by a previous owner. The original single-pane steel sash casement windows had been stored, and are in excellent condition. The building department views these "restored" openings as "new" openings, and requires compliance with the energy code, i.e. window U-factor of 0.30 or better. (The default value for these windows is U=1.20 per Table R303.1.3.)

In Building Code Questions | Asked By Robert Drucker | May 21 15
1 Answer

Use regular OSB or Zip Wall OSB in conjunction with 2" XPS?

My wall plan consists of:
1- fiber cement siding
2- 3/4" air gap/ 1x4 firing strips
3- 15# felt (or possibly Tyvek housewrap) for general protection of the XPS
4- 2" rigid XPS with taped seams and caulked at butt joints
5- 7/16" OSB (possibly taped Zip Wall)
6- 2x4 24OC stud wall with mineral wool or fiberglass insulation
7- 1/2" drywall sealed at top and bottom and around device boxes and penetrations

In Green building techniques | Asked By Nathan Mogilski | May 22 15
6 Answers

Vinyl siding renovation

Hi

In Building Code Questions | Asked By Chris Felker | May 14 15
7 Answers

ADA sealant recommendation please

Hello,
I'd like to air seal my baseboards to my drywall and concrete slab as part of an ADA.
What would you guys use to seal wood to acrylic paint & unfinished concrete?

I picked up some GE Silicone II Gutter & Flashing which says it sticks to wood and concrete, but was wondering if there was a better choice.

Thanks for your help,
-Richard

In General questions | Asked By Richard Baumgarten | May 21 15
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