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1 Answer

Double sheetrock + green glue + Membrane

I am going to be using mineral wool, a certainteed membrane, and possibly 2 layers of sheetrock (1/2" or 5/8") with green glue between them. Is there going to be any problem with this design in terms of the membrane's performance? I don't want moisture problems by using 2 layers of sheetrock + the green glue.

Asked By Ralph S | Apr 24 17
0 Answers

Deep blown in cellulose for attic - questions

I have a few questions regarding deep (beyond R60) blown in cellulose for an attic. Cellulose is relatively cheap and I'd like to maximise my attic insulation without causing any other issues:

1. Several manufacturers of cellulose insulation have depth/R-value charts that stop at R60. Is there any practical reason for this, or is it just because most people don't bother going above R60?

2. Does compression above a certain depth negatively affect the performance of the insulation in any way? I.E. does your R-value/$ go down appreciably beyond a certain depth?

Asked By Lance Peters | Apr 24 17
4 Answers

Steel roof: to sheathe or not to sheathe?

I'm considering a steel roof for our new house build (hip design, 7 or 8:12 pitch) and I'm wondering whether sheeting first with OSB or plywood and a moisture barrier makes sense? I've done a little reading and it seems there are some who are in favor of sheeting and others who see it as a waste of time/money.

The main concern seems to be with moisture condensing under the roof when cool night air drops below the dewpoint of air in the attic. To this I question:

Asked By Lance Peters | Apr 19 17
0 Answers

Air or Vapor barrier for attic (using cellulose)

Is there a certain air or vapor barrier that I should install before hanging ceiling sheetrock? The attic will be insulated with blow in cellulose. The attic will be vented at the soffit and with a ridge vent, nothing else. House is in zone 5. Probably R-40 to R-50 in terms of the amount of cellulose. I am looking at using the Certainteed smart membrane like I will on mineral wool walls.

Asked By Ralph S | Apr 24 17
18 Answers

Warmboard with Ductless System?

Newbie here, so pardon my ignorance.

We are about to start designing a home in the DFW area (Zone 3).
Home will be a 2-story open concept with about 5,000 to 5,500 SF, properly insulated for the area. Despite the size, plans are to go with about 20 KW of grid-tied Solar Panels with a Powerstation 247 system.

Wife wants "Warmboard" as the heating source for at least some of the areas. I would like to have a VRF Ductless System for cooling and heating. Is there anyway to marry the two so that we stay "married" ? :-)

Asked By Rodgo | Apr 19 17
2 Answers

Can straw bales be used on the exterior of a shipping container home?

I am interested in building a shipping container home. Insulation is one of my biggest concerns. I have read a lot about the benefits of straw bales. I am very interested in using this as the exterior insulation, but have not found any info pro or con. Any help will be very beneficial.
Thanks for your info.

Asked By OrrinH | Apr 23 17
5 Answers

Raycore - is it the product for me?

I was pretty much on board with buying Raycore for the 4500 s.f. home I am building in downstate NY, which is steel framed, so I actually don't need any structural value out of the exterior walls other than for supporting the windows and doors (and supporting the walls themselves). I am also going with a wire lathe and stucco on the exterior - Raycore told me I could direct apply the wire lathe and did not have to use any sheathing if I did not need the shear strength, but I am hesitant to do so.

Asked By Joe McCarthy | Jul 14 14
0 Answers

Moisture control / insulation for new cinder block shop with loft / den.

Hello Folks

I've been reading through the forums for an answer to this question, but haven't been successful in finding one. I'm building for the first time, so this is a learning curve for me.

I live in west Florida, and have a project in the works. I'm going to be building a 55ft x 38ft workshop, that will be 2/3 work space, and the remaining 1/3 will be a loft / den living space with a small kitchen, laundry area, and bathroom. So around 1400sq ft. I am planning on controlling climate with a 3 air handler mini split system.

Asked By brew0688 | Apr 24 17
8 Answers

New house build, SIPs?

New member here, we are planning to build a new house this summer and I'm exploring my options for wall systems. I plan to do the framing myself. House will be roughly 2500 sqft in Ottawa, Ontario Canada. Not the coldest place to build but not far off, and just for kicks it gets pretty hot and fairly humid here in summer as well.

Asked By Lance Peters | Jan 15 17
0 Answers

Standard (non-custom) window sizes?

In the interest of getting the "most bang for my buck," I have been trying to find "standard window sizes," as opposed to what is generally advertised as "custom" windows... Perhaps this is something that is available in high performance windows, perhaps at widths which correspond to common framing widths such as 24" OC, 16" OC, etc. I would be happy to design around these parameters, but it seems that most high performance window manufacturers also tout "custom sizes." Does anyone have a lead on standard high performance window sizing?

Asked By Ethan T ; Climate Zone 5A ; ~6000HDD | Apr 24 17
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