Community: Energy efficiency and durability

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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.

Asked By Venkat Y | Aug 29 14
Answers

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.

Asked By Randy Mason | Aug 30 14
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.

I plan on putting a galvanized metal flashing were the bottom of the plywood meets the foundation. I have read numerous articles on this in regards to a horizontal run, but have not found one with details for a stepped foundation. I am assuming that the metal flashing should also run vertically. Have any of you had experience with this detail?

Asked By Randy Mason | Aug 30 14
2 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?

Asked By Jason Haché | 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?

Asked By terry grube | Aug 29 14
Answers

Hi Folks,

I am advising on a home renovation in Sudbury, MA. It has become obvious that the structure -- about 20 years old -- was built without thought to airsealing. The resulting home performance problems are likely predictable to GBA readers.

Now, the owners are turning a 3-season sun room into a 4-season room and need help figuring out how to best heat and cool the new space. This project also presents an opportunity to address other related issues.

Asked By c talwalkar | Aug 30 14
3 Answers

My new house is designed to limit penetrations through the building envelope to as few as possible. Nevertheless, sillcocks, outside electrical receptacles, outside lights, HRV intake/ exhaust, etc. need to be sealed.
Are there methods or products that are more effective than others? How about ease of installation? I've seen photos of tape covering holes and that seems like a pretty clunky solution. I'm probably going to either do much of the airsealing myself, or at least supervise it.
Thanks for any advice.

Asked By stephen sheehy | Aug 29 14
1 Answer

I understand from prior posts there are concerns with the flash foam and fiberglass insulation in terms of moisture vapor.

Would the use of proper barriers and Roxul instead of fiberglass help to abate that concern?

Asked By George Levicki | Aug 29 14
3 Answers

Here are the facts about this house first;

Asked By Richard Beyer | Aug 29 14
6 Answers

Hi all,

New owner of a 1 1/2 level cape here. Finished upstairs. Zone 5. I'm experienced with home renovations and DIY, but new to Capes.

Trying to bring upstairs environmentals in line with lower level conditioned home temps year round without running the mechanicals 24 /7.

No insulation to speak of. No ventilation. No vapor barrier. Planning to make the attic "outside space".

I've blocked all of the underfloor joist bays, sealed all chases and penetrations, insulated the kneewall hatches very well, etc. This has helped a lot.

Next steps:

Asked By M Welch | Aug 27 14
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