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5 Answers

Questions on building an attic storage deck

Hi folks,

I'm embarking on my next project, which is to build an insulated storage deck in my vented attic. First some context:

This is an addition to the house, which comprises a sunken fireplace room over a crawl space and a 2 car garage over a slab. Then there is a stick framed attic over both of these spaces. The walls are 2x4 studs in these rooms, and the ceiling is made of 2x6's.

In General questions | Asked By Ryan O'Rourke | Mar 11 16
2 Answers

Disable attic fan or leave alone?

I recently bought a house that has an attic fan on a thermostat that seems to run whenever the outside temperature gets above about 70. The house was constructed in 1958, and is 2x6 wood frame on 16" centers. The attic has about 2-3" of blown-in cellulose, is pitched (I don't know the pitch but it's about average for a typical suburban house), and has a gable vent on each end (L-shaped house), soffit vents, and ridge vents.

This is in Albuquerque, NM, where it's very dry and very hot in summer (90-110 degrees is a normal high from May - September).

In Energy efficiency and durability | Asked By Gen Lawson | Mar 14 16
2 Answers

Risky wall assembly design with stucco/stone over 2.5" XPS outsulation

Building in Zone 5, NE US want to adhere to the concept of outsulation and break up thermal bridging of 2x6 stick framing (sheathing is 5/8" plywood) and add 12.5 R-value to the wall. Final exterior product planned to be a combination of stucco and stone veneer (lick and stick).

In Energy efficiency and durability | Asked By Sal Lombardo | Mar 15 16
2 Answers

Where to look for industry data?

I have been a Green Building Advisor member for several years and used advice from this community to build an Earthcraft Platinum home.

I am hoping that you can help me to locate some information for a work-related project.

One of my clients has engaged me to write a white paper for a new sheathing product that has an integral water and air barrier. My audience is architects, builders, and specifiers who primarily serve the commercial market.

I would like to reference industry data on the following:

In Green building techniques | Asked By Steve Knapp CZ 3A Georgia | Mar 15 16
1 Answer

I have a question about insulating the attic space in an addition

I am planning a 360 square foot addition with a 12 x 12 gable roof so there will be a large attic space. The ceiling will be 2 x 12 joists to allow for a clear space in the room below. I will put r-38 fiberglas between the ceiling joists to meet code. My question is if I later choose to insulate the roof rafters later on can I leave the insulation in the ceiling?

In Building Code Questions | Asked By Bruce Sukennik | Mar 15 16
9 Answers

Uni-Solar peel-and-stick for standing seam roofs

Is anything like Uni-Solar Powerbond still made?

It seems like a much much more aesthetic form of PV than conventional panels, especially if it were sized correctly to cover the whole south-facing side of a roof. The ideal would be a solar shingle solution that actually looked like shingles or slates, but this doesn't seem to exist.

I know Uni-Solar filed for bankruptcy so I assume this product isn't being made any more? Is that the case? If so, where did it all go wrong?

In Green products and materials | Asked By F W | Apr 10 14
16 Answers

Subslab insulation and bearing wall footings

I am getting ready to do the foundation work on the new home we are finally getting started with. I have some load bearing walls in the basement that will sit on poured footers. The footers are -2" down from the bottom of the slab so the insulation can extend over the projection and run into the foam on the ICF wall. However for the interior load bearing walls, I was considering installing these
-2" as well and continue the foam over top of them, and then the slab. As we all know compressive strength of XPS foam far exceeds loads imposed in residential applications.

In Energy efficiency and durability | Asked By Jesse Lizer | Oct 3 12
3 Answers

Sub-slab insulation under a bearing wall?

There was a previous post very similar to my situation posted back in 2012....I am looking for any new or additional clarification on this question. I have two interior 2x6 bearing walls, 30' long which my engineer says must be able to support 700 lbs per foot. He requested a footer with the slab turned down to sit directly on the top of that footer. I would prefer to run my 2" thick EPS insulation... rated at 40psi....continuously across the whole bed of 4" crushed stone which would also run across the top of the footing.

In Building Code Questions | Asked By Jonathan Scholl | Mar 14 16
2 Answers

steel roof

I think you need to know you have given me all that i need to know ,but you need to know i am working on a low slope roof and im asking about elastometic to repair an area of ponding with damage and poor attempts to fix it but if no one wants to help me with a recomendation I guess i'll ask elsewhere gee thanks

In General questions | Asked By Steven Montgomery | Mar 14 16
2 Answers

Lead plumbing boot flashing safe?

We are having a standing seam metal roof installed and they are planning on using lead plumbing boot flashings to seal the roof roof vent pipe penetrations. I'm sure many of you have metal roofs so hopefully someone will be able to give some insight.

It sounds to me like the lead flashings are considered the method with the most longevity (vs something like those plastic boots), which is important in a metal roof since it should have a long lifetime before replacing.

In General questions | Asked By Nick Hall | Mar 14 16
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