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2 Answers

Best way to air seal and insulate floor and wall assemblies

I'm remodeling a house in climate zone 4 outside Seattle. The existing exterior walls are 2x4 with 1x8 board sheathing. I want to achieve the required R21 insulation value without having to fur our the wall to achieve a 51/2" wall cavity while also sealing the 1x8 sheathing. The subfloors are 2x6 T&G and I want to seal the floor assembly and achieve the minimum R30 insulation value. What would be the best strategy to achieve these goals?

In GBA Pro help | Asked By Stewart Breslin | Jan 21 17
7 Answers

Product for permeable lawn/grass instead of concrete paving

Seeking your advice on which is the best among that permeable products that allow you to have a lawn in an area that receives residential vehicular traffic and would normally be paved with concrete.

In Green products and materials | Asked By c l | Jan 20 17
1 Answer

Continuous Insulation - Mix under rafter and between rafter?

I am creating a semi-conditioned space in the attic over the top of my garage in Texas. I am using foil backed, 1 inch 4x8 sheets of polyiso foam, stacked 4 inches thick. I planned on doing an under rafter installation.

    My setup:
In Energy efficiency and durability | Asked By Nigel Campbell | Jan 22 17
2 Answers

Clearance for HPWH

I'm considering putting a heat pump water heater into a bathroom/laundry room. The room has plenty of volume. I'm concerned about the clearances needed though. The Accelera models claim to need a 2' clearance at the intake, and a 6' clearance at the exhaust. That seems to limit the usage of this to rooms with a 10' clear strip for the water heater. I know efficiency will suffer if it recycles air, but this seems excessive. Does anybody actually do this? If not, what are reasonable clearances?

In Mechanicals | Asked By John Ranson | Jan 22 17
7 Answers

Rental wall

Hello, I've been digging through the wealth of information here at GBA and have gotten some really good ideas and a much better understanding of theory that is really helpful, but I have a few questions. Im making plans to build a simple 16x30 1.5 story cabin, with balloon framed 12ft walls and 12/12 roof in Homer, AK, an oceanfront town which is in zone 7 from what I can find. I want to build it to be energy efficient and tight, but not extreme. The plan is for it to be a rental, so durability is the biggest concern.

In Energy efficiency and durability | Asked By Aaron Bonnett | Jan 21 17
2 Answers

Does this look like asbestos insulation?

Hi there! Cleaning out a home built in 1955 and came across this material. Does it look like asbestos?

In General questions | Asked By Ann Smith | Jan 22 17
4 Answers

Does anyone have a Mitsubishi ductless minisplit commissioning procedure?

Is anyone very familiar with the commissioning process of a Mitsubishi Ductless Mini-split? I am a stones throw away from zone 6 and had a Mitsubishi diamond contractor install what was supposed to be a hyper heating condenser unit. Instead the contractor installed the MXZ-3C30NA2 which is a non hyper heat unit.

In Mechanicals | Asked By Dillon Vautrin | Jan 21 17
13 Answers

Could you moderate first posts to stop the flood of spam?

Recently, I haven't been reading the Q&A on GBA, because it's always full of spam. Could I suggest that you moderate the first several posts by any non GBA Pro user who hasn't posted before? The idea being that you either have to pay for a subscription or post three moderated and approved posts before you get unfettered access to the forums.

In General questions | Asked By John Ranson | Jan 19 17
2 Answers

Metal Roof for a 1:12 Pitch

Does anyone make a metal roof that can be used on a 1:12 pitch?

20PSF snow load

In General questions | Asked By Peter L | Jan 23 17
5 Answers

Should I install a vapor barrier under a LVT (Luxury Vinyl Tile) flooring material?

Existing home has an inordinate amount of moisture/water under the raised wood floor (two-story SFD structure).

Realizing that the moisture should be mitigated by possibly at least installing an impermeable moisture barrier at dirt, I am wondering (assuming owners do not elect to install mitigation in crawl space) if the floor assembly should be as follows?

Existing Plywood Subfloor
Vapor Barrier (6 mil poly)
Plywood Underlayment
Floating Click system LVT

In GBA Pro help | Asked By Bill Reid | Mar 16 16
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