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24 Answers

Do heat pumps and super insulation complement or compete with each other?

After reading the article on "how much insulation is too much", I found Marc Rosenbaum's stats on 11 cold climate house configurations interesting. He points out that the difference in energy savings is very small between a minimally insulated and poorly air sealed house and a super insulated and very tight air sealed house. This is because he starts with an 2.5 cop heat pump and a heat pump domestic water heater. He sets the miscellaneous loads (appliances and lighting) at 4800 kwh year. The domestic hot water at 1850 kwh year, and the only variable is space heat.

Asked By ven sonata | May 29 16
0 Answers

Should I be concerned with these wall and roof insulation details?

Hi,

I am a weatherization contractor located in coastal MA, climate zone 5. After reviewing countless articles here and from Joesph Lstiburek's website, I'm concerned that the plans I received for a new construction project are not optimal and may pose problems down the road for the homeowner. Specifically, I'm looking to see if my concerns are accurate or if the plans are acceptable. My questions/concerns are (images for walls and ceiling as attached):

Asked By Corey Ricci-Munn | May 30 16
2 Answers

Raft slab edge insulation detail

Hi - I'm building a home in Central Vermont (Zone 6) this summer and had a question regarding slab edge detailing.

Asked By Craig Bunten | May 29 16
0 Answers

Building an energy-efficient metal building

We are in the process of planning a metal pole barn used for manufacturing. We need to have metal panels on the inside (or similar) for wash down. We currently have a similar metal pole barn which is not energy efficient. What is a good way to make better use of the insulation / materials to make the building as energy efficient as possible? We also need to maintain a constant temperature of 55-65 degrees if possible.

Asked By Becky Parrish | May 30 16
36 Answers

Best exterior wall design within standard 2x8 dimensions

I have been reading several of the GBA posts and articles and I don’t seem to locate the answer to my question so I wanted to drop you a line by email.

I am located in Saskatchewan, Canada and currently have a house under construction that is well under way. That being said I won’t over complicate it with detail but the house is not a high efficiency design and I am not and don't pretend to be knowledgeable on a lot of points that are covered on GBA.

Hhowever, this is what i have

Construction detail:

Southeast corner of Saskatchewan, Canada 15 miles north of North Dakota

Asked By chad online:) | Feb 21 16
27 Answers

Exterior rigid foam and re-siding project

I'm seeking input and opinion. I'm looking to re-side with the dread vinyl (need the low maintenance for my two story house). My 40 year old post and bean house has interior sheetrock, 3.5" of fiberglass batt insulation with kraft paper, rough cut full 2x4 studs on 24" centers, plywood sheathing (I think 5/8"), paper (a mix of Tyvek and felt), and cedar shingles. Shingles and paper will of course be removed, sheathing inspected in the process. I'm in zone 6.

Asked By Howard Gentler | May 2 16
2 Answers

Insulating walk-out basement

I'm insulating a walk-out basement in a new construction. The house is of a double wall design, and will be filled with dense pack cellulose. I understand that for the foundation walls that I can not apply cellulose directly, however I had thought that if I apply a layer of closed-cell either sprayed or laid in in sheets then I should be able to fill the rest of the cavity with cellulose, assuming that there is no concrete exposed. My question is how many inches do I need to use to assure I have no problems with the cellulose?

Asked By Geoff Frood | May 29 16
3 Answers

Conditioned crawlspace, floor insulation

I think every drawing & article I've read showed no insulation on the floor of a conditioned crawlspace. So far, I haven't found any recent info on the heatloss into the ground or temperature of the ground below a conditioned crawlspace. There's something in my old ASHRAE fundamentals for a basement floor, but it seems too high. It would seem that if there more than a little heat loss it should be insulated?

Asked By brad h | May 29 16
2 Answers

Is R-1 fan-fold insulation cost-effective as vinyl siding underlayment?

I am installing vinyl siding on a home in Pittsburgh PA as part of a HUD financed project. As such, HUD has supplied the specs. The requirement is for R1 fanfold followed by Tyvec. I think that the principal function of fan fold has traditionally, pre-house wrap, been to limit air infiltration (not provide R value), a function that is in this case served, redundantly, by the by the Tyvec.
There is almost no wall insulation and no plans to install any soon but there is adequate attic floor insulation.

Asked By Thomas Rydle | May 29 16
1 Answer

Instananeous hot water with a tank

I'm looking for the manufacturer of an instantaneous hot water heater with a thirty gallon tank mounted above it. The manufacturer advertises it as a complete unit. Any info will be appreciated.
Scott

Asked By Scott Goodman | May 29 16
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