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1 Answer

Unvented roof assemblies without spray foam

I am planning an addition on my home in Seattle with an unvented roof assembly. I have looked at the costs and I am not considering using spray foam of any kind.

For an unvented, cathedral ceiling, the local code calls for R-38.

In Energy efficiency and durability | Asked By User-6965270 | Dec 7 17
2 Answers

Efficient shower stall design: Airflow?

So I'm kicking around ideas for efficient shower designs. Our master bath will have a shower stall that is recessed with three tile walls, and one glass wall with a glass door panel more or less flush with the side of the bathroom.

The glass wall will have three parts; two stationary panels and a door in the middle.

In Green building techniques | Asked By Lance Peters | Dec 6 17
12 Answers

Double stud framing insulation

We are building our full time retirement home in zone 5 in Lakeside Arizona. We want to use a double studded framing system to take advantage of the thermal break option.. What are our best options for insulation? and what are the R values of each option listed. See attachment:
1:Open Cell Foam Insulation 2x4 primary Dense Pack Cellulose / wool insulation for 2x4 secondary wall
Option 2:All dense Pack cellulose or wool
Option 3 Use 2x6 with either open cell foam or dense pack cellulose or wool 5 ½ inches

In Green building techniques | Asked By r ferd | Dec 4 17
4 Answers

Solutions to inadequate insulation at truss heel

After recently reading "Prevent Ice Dams with air sealing and insulation" I know that I am not currently able to get the insulation I want at the heel of my standard trusses.

I will be building a double stud wall inside an existing structure, which will help increase the effective insulation at the inner top plate, but there will still only be approximately 9 inches of available space measured normal (perpendicular) to the roof sheathing where the trusses meet the (inner) top plate.

Zone 6a (Maine)

I have a number of thoughts:

In Green building techniques | Asked By Tyler Keniston | Dec 5 17
4 Answers

Adding to existing blown-in fiberglass insulation


I am located in climate zone 5, bordering 6. I have remedied sealing and kneewall issues in my attic. I am ready to add additional blown-in insulation to the existing blown in fiberglass (R-38). My plan is to bring the final R value to R-60. If I currently have blown-in fiberglass, is there any benefit to adding cellulose over the top or just top it off with additional blown fiberglass?

Many Thanks,

In Energy efficiency and durability | Asked By Mg6467 | Dec 4 17
11 Answers
5 Answers

Why is my canned spray foam product inconsistent?

I'm using Great Stuff Pro spray foam (windows & doors, as well as gaps and cracks) with the Pro 14 gun, and I keep getting the same problem occur. The first 10-20 linear feet or so I spray out of a fresh can seems to come out of the gun really well, but when it drys it'll get super hard and crumbly. After the first 10-20 feet it comes out of the gun super slow, and cures more like it should. So I ether get good application, poor end product, or vice versa.

In Green products and materials | Asked By Adam Peterson | Dec 4 17
6 Answers

Removing stapled kraft-faced fiberglass batts

I have an attic with Kraft Faced Fiberglass Batts that are stapled between the joists. I'm looking to air seal the attic floor but this will entail ripping the kraft facing in order to remove them.

Am I better off leaving it alone and not ripping the paper (I know it acts as a vapor retarder) or does it not really matter if I rip the paper where it's stapled and then just place the batts back in between the joists after air sealing?

Thanks for the input!

In General questions | Asked By BuildingNewb | Dec 6 17
14 Answers

Dense-packed cellulose in attic rafters with Ice and Water Shield on exterior

After having an energy audit perform, it was recommended that I have the attic rafters dense packed with cellulose opposed to insulating/air sealing floor in order to bring the HVAC equipment up there into the conditioned space. Also, 3 cathedral ceilings going into the attic made doing the floor too challenging.

In Energy efficiency and durability | Asked By BuildingNewb | Dec 5 17
1 Answer

Exterior wall options for southern Manitoba

Good evening we are in the planning stages of building a new house. The builder has given us an option of 2x4 walls in the build. They can be upgraded to 2x8 with staggered 2x4s, or a double wall system 2x6 with a 2x4 wall. What would be some recommendations. I like the idea of the larson truss system. Would they build a interior 2x4 wall then add the larson system to the outside? What could be the potential cost differences between each option. I am curious about the R value for walls ROI.



In Green building techniques | Asked By Bryonfriesen | Dec 5 17
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