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1 Answer

Insulating Cantilever Space Containing Water Pipes Zone 4A No. VA

I am wondering what is the best way to insulate a cantilever space containing hot/cold supply pipes and a bathroom exhaust vent. Above the cantilever is a bathroom, below is the entrance to my house and on the inside another bathroom. Currently there is only fiberglass, no blocking, no foam, no sealants. The pipes have been there since 1984 and since I live in a middle unit townhouse they will not be moved.

Asked By Alex Chandler | Sep 20 14
4 Answers

Air and moisture proofing

I am going to be renovating a 1950’s house in Toronto, ON. It’s a 1 ½ storey that we are making 2 storey with adding addition on the back and attached garage. The plan for the 2nd storey is wrap the outside in Blueskin then cover in 3” Roxul Comfortboard IS, Strap and vinyl side. 3 of the 1st floor brick walls are to be left in place, which I also want to cover in 3” Roxul strap and vinyl side, but unsure what to use under it to keep the air and moisture out.

Asked By Dave B | Sep 18 14
2 Answers

A layer of 1" XPS foam between fiberglass batts?

I live in MN and am working on a complete interior remodel. The exterior walls are 2"x6" w/ R19 fiberglass batt insulation, some with Kraft back & some with poly on the interior side. I would like to try & at least double the R value, but due to other design constraints would like to keep the additional interior intrusion to a minimum (exterior insulation is not possible).

Asked By Joshua Streblow | Sep 19 14
3 Answers

Insulating and air-sealing a room-in-truss over a garage

Hello,
I am looking for some clarification on insulation and air-sealing, when dealing with room-in-truss construction for a conditioned space over a garage.
I live in Michigan, climate zone 5. I have a 28x36 garage, with 28ft span 8/12pitch "attic" trusses. the trusses have a 2x10 bottom chord and 2x8 top chords with 2x4's at the kneewall. I have a permanent stairwell going to the room in the truss, and I plan to heat the room. I have in-slab hydronic heating on the garage floor.

Asked By Ben Helmreich | Sep 15 14
2 Answers

Thoughts on insulating — renovation

I ‘m trying to decide what insulation value to go with on a house we are renovating in Toronto, ON. It’s a 1 ½ storey that we are making 2 storey with adding addition on the back and attached garage.

The 1st storey walls are to be left, 1950s double brick walls no insulation. The 2nd storey I would like to go with either 2x6 with R24 Roxul or 2x8 R28 or 2x4 x2 with 3xR14=R42 and 3”Roxul Comfort board IS R12 on the outside.

Asked By Dave Bentley | Sep 18 14
1 Answer

Metal building — office insulation

Architectural details indicate insulation at 16-18' ceiling heights and vertical walls with methods typical of metal buildings. Offices being built inside much like a story and a half home due to headroom at eaves verses the center of the building. Heating units and distribution is hung from roof structure above 8' suspended ceiling.

I'm of the opinion that a raftered ceiling at 10' or so with drywall and blown cellulose insulation will: -Provide a tighter envelope.
-Reduce the amount of conditioned space.

Asked By William Sauder | Sep 18 14
6 Answers

Has the Oak Ridge study on convective heat loss in blown fiberglass been updated to cover newer materials?

I'm evaluating blown cellulose vs. blown fiberglass (Knauf Ecofill). The Oak Ridge study is often quoted regarding the drop in R-value of blown fiberglass when the temperature differential is high. However the tested fiberglass density (.4 - 5 lb/ft^3) is much lower than the newer fiberglass.

Asked By Neil Weinstock | Jul 21 14
4 Answers

Trying to determine best assembly to insulate an old church roof being converted to office

We are looking to keep the existing roof decking and rafters exposed in a church in Atlanta, Climate Zone 3. We have read Martin Holladay's FHB Article about unvented, Super Insulated Roofs, and Joe LUtiburek's article BSI-036 Complex 3D Air Flows talking about the subject. One of the big differences (really somewhat minor) I see between the two recommended details is the best place to locate the fully adhered air barrier. Martin shows placing it at the outermost layer right on top of the new sheathing, right below the roofing material. In this case asphalt shingles.

Asked By Eric Kronberg | Sep 16 14
4 Answers

Out-sulation vs Double Stud Walls

I was reading some old GBA discussions about double-stud wall designs and the added difficulty of keeping the sheathing dry (relative to wall designs that place appropriate amounts of insulation over the sheathing). This prompts me to wonder why the double-stud approach has its adherents when an out-sulation approach can be used to achieve the similar R-values and protect against thermal bridging while dispensing with the uncertainty regarding moisture. Besides being of general interest to me, I am hoping the responses will help me decide the 'best' way to proceed for a future project.

Asked By Rob Shuman | Sep 16 14
15 Answers

Spray foam & wood roof deck

100 year old residence is located in Zone 5 w/i 50 ft of ocean/bay & has a 100 mph design wind load requirement. It is located high on a hill & completely exposed. Vented eave ridge is not advisable in this area do to high driven rains. The home will not be the primary residence, therefor optimal heating, venting & dehumidifying will not be maintained 24/7.

The energy code requires 49R roof assembly for the proposed occupied attic w/ cathedral ceiling. 49R requirements & existing 2x8 rafters, limits choice of insulation to closed cell spray foam.

Asked By Sheila Sullivan | Sep 12 14
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