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16 Answers

Rising power plant energy cost

See attached....SDG$E(San Diego, CA) raised the minimum tier from 12 cents to 15. We don't buy in and didn't run the AC much this year in baking heat, probably what most are doing, that and getting off the grid. This is sign of those still on the grid having to pay for the ones that are off. In KS, cost went down from 10 cents last year, to 9 probably in fear of going bankrupt like Cali. Lets see what they do with gas.

How about where you live, going up or down?

Asked By Terry Lee | Oct 15 14
15 Answers

Enclosed room on slab

In the midst of an enclosed porch over slab job. Plans initially included flash on un-vented roof, rigid foam on exterior, house wrap and fiberglass in walls.

Asked By Jason Schatz | Oct 16 14
5 Answers

Reasonable retrofit efficiency goals

As I battle with an hvac solution for our home, we are leaning more and more towards trying to reduce the load further. I'll mention some details of my own house a bit below but I'm actually asking in hopes of a more generalized discussion of what a reasonable retrofit btu and ACH50 goal is.

I did some reading tonight in the hopes of answering this question but didn't find any useful rules of thumb. I know, the old HVAC rules of thumb have caused a lot of grief. I'm not asking for a rule of thumb about BTUs/sf for heat but rather what is rationally achievable in a retrofit scenario.

Asked By Keith H | Oct 19 14
3 Answers

Unusual thermal envelope intrusion at roof-penthouse


I've discovered that the ~1987 penthouse addition to my house is partially outside the roof thermal envelope . Since it is attached (naturally) to the remainder of the house it compromises the performance of the whole house.

In a nutshell:

Asked By Keith H | Oct 14 14
10 Answers

Choose between more/better insulation, or heat pump?...

Last year we had an energy assessment performed in our 1880's home and were recommended several options. We opted to first pursue air sealing in attic with 20" of blown in cellulose. This made quite a difference both in comfort and heating bills.

Our remaining recommendations:

1 - Insulate walls with dense pack blown in cellulose.
2 - Insulate crawlspace (closed cell spray foam).
3 - Replace 4 windows original to house (drafty!!)
4 - Install high efficiency air source heat pump.

Asked By Christian Rodriguez | Oct 9 14
1 Answer

Thoughts of REMOTE style building in eastern Canada

Dreaming of building a home aprox. 26x30 two story facing towards south with two large triple glaze casement windows (5'x5') per floor, my thoughts are to use REMOTE on a slab with 4" of exterior foam (eps) and blow in or roxul with in the stud cavities (2x6). The main reason, I am wishing to use REMOTE is for airtightness, plus the thoughts of having less wetting on the sheathing. Am I barking up the wrong tree? The home with be built in Charlottetown, PE.
I know this is very basic info, wishing to heat with minisplit.
Thanks Marty

Asked By marty nichol | Oct 15 14
6 Answers

How do I cost effectively insulate the ceilings of my detached garage?

I have a 22x22 detached garage with a 15x15 addition on the back (both gable roofs) that I'm turning into a shop. I live in Iowa and have run a gas line to it and have purchased a gas heater capable of heating. I would like to heat the garage at low heat and will crank it for shop time. Each space has 2x4 rafters, but no insulation, no ridge vent or other roof venting and only one of the two spaces allows free flowing air to enter the building through the rafters running beyond the building envelope as the 22x space has wood blocking.

Asked By Matt McDevitt | Oct 12 14
17 Answers

Correct way to use closed-cell insulation on a roof?

I'm rehabbing an old 3-story brick building in Pittsburgh. The roof is a flat roof but pitched from front to back. I got estimates to spray closed-cell on the underside of the roof and essentially encapsulate the structure. There is a 'space' between the 3rd-story ceiling and the roof, so if I drywall the 3rd-story ceiling, there would then be an air space above the drywall. I'm also planning on installing a new rubber roof. So I guess I have several questions:

1. Is applying closed-cell to create a barrier at the underside of the roof the correct way to go?

Asked By John Murphy | Oct 8 14
2 Answers

Skirting for Cabin

My cabin was built on piers and has no skirting to protect the pipes beneath the house. I'm trying to find something that's energy efficient and attractive. In searches on the internet, all the skirting I find seems to be for mobile homes. Can you suggest skirting materials that will work best for keeping out the cold in the mountains of North Carolina? Currently it just has tar paper and lattice ... (The cabin is on a knoll and gets some very cold wind).

Thank you!

Asked By Leslie Elliott | Oct 10 14
4 Answers

Small house up North

I'm currently planning a home for when I retire. It's in a maritime region, 57 degrees N with 3200 HDD. I'm considering a small house (~1000sf) on a single story. The selected site has clear view to the south and the long axis of the house can be aligned E-W so solar is an obvious consideration. The house will be heavily insulated and built tightly. I would like to know whether or not a combination of direct solar, thermal mass and solar P-V would be a good starting point for the design. I have access to my own wood for winter warmth.


Asked By Peter Hastings | Oct 10 14
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