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16 Answers

Rigid foam interior or exterior of basement?

I live in zone 5 and am planning to start the concrete work next month. Right now I am at or just over budget without factoring in any rigid foam insulation for the basement.

Asked By Nicholas C | Apr 6 15
8 Answers

Is there a standard factor General Contractors use when calculating their fee to construct

I am in discussion with a builder to construct my new home in zone 4B. We have engaged the services of an energy modeler to determine how to build the most efficient house within the budget. We are grossly over budget, at the moment. I noted that the GC has build a 16% fee into the budget to build the house. This is on top of all the subs and the contigency. Not wanting to negotiate something I have no background on, I'm wondering if this is a negotiated fee or is there some standard? I understand my builder needs to make a profit but I would love to get 16% return on my investments!

Asked By scott schroeder | May 22 15
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.

Asked By Keith Richtman | Aug 14 14
2 Answers

Membrane in unvented roof

I am installing 1x6 T&G boards above my 2x8 rafers in an addition cathedral ceiling project. I plan to follow with a layer of 5/8" plywood (for roof structure), and 6 inches of polyiso above that.

Asked By Harold Orozco | Apr 30 15
1 Answer

OSB versus Styrofoam

I live in climate 3 in warm humid Louisiana and will be building in the next six months. Most of the builders in the area use OSB in the corners and 1/2 styrofoam over the rest of the home for sheathing. I understand the styrofoam has much better insulating value than OSB but I also don't want a home that is structurally weak in a wind storm. Any advice on this?

Asked By Shane sims | May 22 15
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

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.

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

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).

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).

Asked By D Wadsworth | Jan 28 15
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