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2 Answers

Hello,
I have a 1 1/2 story cabin that I am insulating. The second story was constructed using engineered attic trusses. The top chords are 2 x 6 and the knee walls are 2 x 4. Metal roof with soffit vents and ridge vents. My plan is to fur the sloped top chord with a 2 x 4 on edge. This would provide me with 9" of space. I will put allow 2" of ventilation space and install 1.5 " XPS rigid foam board as my baffles, followed by 5.5" of roxul comfort batts, 6 mil poly vapour barrier and drywall. The 2 x 4 kneewall I will build out also with 2 x 4, giving me 7 inches of space to fill.

In General questions | Asked By Dawn Roberts | Aug 30 14
17 Answers

I would like to decide on putting in solar panels to reduce energy costs.

I have read about the next generation solar panels not being to far off.

Question: Would it be better to install current solar panels or wait for the new type that will be coming shortly?

In Green products and materials | Asked By John Alberti | Aug 26 14
3 Answers

Hi,
I am currently redoing the exterior of my house with a new vinyl siding and changing all windows. My house was built in the mid 80's and have 2x6 studs with Batt Insulation and mostly without a vapor barrier... but the insulation is not great, especially the air goes through the house.
My question is what is the best insulation for me to put outside the house underneath the vinyl siding. My windows will allow me to go up to 1 inches of exterior insulation.
So XPS with Typar? Polyisocyanurate (IKO Ener Air )? Others?

In Energy efficiency and durability | Asked By Jason Haché | Aug 29 14
9 Answers

My designer and I are designing a house as close to passivhaus standards as we can get. We have agreed to design it with SIPs but he thinks a truss roof with spray insulation would work just as well. I'm thinking a SIP roof eliminates potential for thermal bridging and is less costly to install versus the truss roof.

In Green building techniques | Asked By scott schroeder | Aug 29 14
4 Answers

I am replacing my existing siding and I am doing the following -stud - 5/8" plywood - 1-1/2" of Polyisol, 3/8" rain screen, WRB, fiber cement siding. The house is in the San Francisco bay area on a hill with a stepped foundation.

In Energy efficiency and durability | Asked By Randy Mason | Aug 30 14
3 Answers

Could a roofer possibly give an explanation as to what is occurring near my eave adjacent to a side wall. I have included pics. This has been about 8- 10 years in the making. There is currently a small depression (pic 1875) which is from deteriorating decking, but for 8-10 years there was dripping from underneath the soffitt below where this depression is pic 1871. The water also runs down alongside the house - pic 1869. (This water is not coming from the eave trough.

In General questions | Asked By eric michael | Aug 30 14
1 Answer

I live in the San Francisco bay area and am going to use 1-1/2" rigid foam board and a rain screen on the exterior of my house. I have read numerous articles in regards to using insect screen at the tops and bottoms of the rainscreen wall, however no specific details about the type of insect screen is ever mentioned.

There are numerous types of insect screens (Aluminum, Fiberglass Bronze, galvanized, etc.) available.

In Energy efficiency and durability | Asked By Randy Mason | Aug 30 14
6 Answers

My 1927 house has balloon framing, real plaster walls on rock lath, and no vapor barrier. It has cedar shingles over tar paper.

If I blow insulation into the walls, will I create a problem with vapor from the house condensing inside the walls? Even without insulation (current condition), can I close the top of the walls in the attic or will that also allow water vapor to condense in the walls?

In General questions | Asked By RUTH HENDRICKSON | Aug 29 14
5 Answers

I am in zone 5A and I have a problem of excess humidity in my ICF home with no abnormal sources of moisture (5 occupants of a 2150 sft home with a full basement). This results in condensation on the wall of windows facing a pond on the north.

Since a dehumidifier will also dump heat into the home helping my all-electric furnace heat the home, I am wondering if it would cheaper to run the dehumidifier than to use an ERV to lessen the humidity in the home. I realize in the latter case, there's some loss of sensible heat that the electric furnace would then have to compensate for.

TIA.

In Energy efficiency and durability | Asked By Venkat Y | Aug 29 14
1 Answer

So based on everything thing I am reading should we be using R3 R4 or R5 for each inch of Polyiso since it decreases in performance as it gets colder. I seem to be seeing some variation in Answers. I am in zone 5 and was planning on putting 5 inches of Polyiso.(thinking that was R 30 Roughly but if is is only R 15 when coldest that is a problem) Now it seems like I would be better served with three inches of polyiso with EPS on top. I have access to 1.5 or 2.75 inch EPS. Would I still be OK with 3 inches of polyiso and 2.75 inch of EPS on top?

In Energy efficiency and durability | Asked By terry grube | Aug 29 14
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