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7 Answers

Insulating a "3-Season Room" or Sunroom in the Mid-Atlantic

My house was built in 1955 with a north-side carport (driveway extended under, roof extended over - including attic with loose-fill insulation, supported by four load-bearing brick columns presumably with footers below) - in the 70s, it was closed in (2x4 framing, plywood, vinyl siding, and jalousie windows. It was ducted for heat and air conditioning although the ducts remain closed. Since we moved in, we replaced the windows with nicer/newer/normal vinyl, and we replaced our HVAC and had them size it such that it would support the sunroom if it were ever insulated/sealed.

In Energy efficiency and durability | Asked By Cory McConnell | Apr 13 15
28 Answers

Rainscreen differences when using mineral wool rather than foam?

Need to replace siding and roofing on my 1942-vintage house. Climate 4C. 8-in-12 gable roof. 2x4 walls.

Because I'll be removing all the contact-clad stucco and replacing it with rainscreened Hardi-Board, I thought it would be a good opportunity to add insulation to the outside of the house (right down to the footings). Ditto with the roof. Thought it'd be a good opportunity to add on over/under-roof with an air gap on top of the new insulation.

In Green products and materials | Asked By John Charlesworth | Apr 9 15
5 Answers

Trying to get quotes on windows for our renovation project in North Vancouver, BC.

I am trying to get quotes on windows for our renovation project in North Vancouver, BC. What a headache. Where do I start?

I would like to have an energy efficient window so my options are double pane or triple pane with 1 low-e coating or 2 low-e coatings. And then you determine which low-e glass you need; 180,270, or 366 Cardinal is the most common.

In Green products and materials | Asked By Aaron Gatzke | Apr 12 15
5 Answers

Metal Roof SRI ratings

If a "cool roof" design has a SRI of 40 would going for a SRI of 54 make that much more of a difference?

Does having a cool roof help with the R-Value of roof assembly? According to the manufacturer they quote ORNL as saying it does help with summer time A/C loads, especially in high-desert climates.

In Energy efficiency and durability | Asked By Peter L | Apr 12 15
15 Answers

Feedback on exterior wall plan for tiny house

My husband and I are about to start building an 8x20' tiny house on wheels, and I'm trying to devise walls that will insulate us well, provide the appropriate air and vapor barriers, and stay as thin as possible to leave plenty of living space. I'd really appreciate any feedback you all can give on our plans! For reference, we are in Nashville, TN, climate zone 4.

From interior to exterior, we are planning:

* Wood tongue-and-groove planks (drywall is too brittle for moving houses)

In General questions | Asked By Michaela Riley | Apr 8 15
4 Answers

How long can the air tightness of construction be maintained?

I'm fascinated by passive construction, however I have a nagging concern about it's durability. I keep seeing "insulation last better than PV". That's great, but the insulation doesn't matter once the air tightness is lost. Due to the the extreme air tightness built deep into the construction, how can simple things like caulking and other decomposing materials be replenished? After 30 years are you left without an airtight house and no heating/cooling system?

In Energy efficiency and durability | Asked By Linee Baird | Apr 11 15
5 Answers

What roof underlayment can be used on a non-vented metal roof?

I've put up a building that has a 14/12 pitch non vented roof but now the building inspection dept. is hassling me over using Titanium UDL30 underlayment under the metal roof. They say it doesn't breathe and can rot the roof sheathing. The ceiling is R49 with 4" of foam against the plywood sheathing followed by 8" of fiberglass and 2 layers of 5/8" firesheild drywall.

I'd like to know 2 things - are my building officials wrong and if they're not what type of underlayment is allowable under a hot metal roof? I'm in the midwest in zone 6a.

In GBA Pro help | Asked By TeleTooler | Apr 11 15
3 Answers

Best subfloor for moisture and insulation under a basement rubber floor?

I would like to put a Roppe rubber floor down in my basement; it's soft and warm on the feet. I have an 80 yr. old concrete slab over which I'd like to add some moisture mitigation and insulation. The installation folks at Roppe suggest a 2 part epoxy paint on the concrete such as Mapei Planiseal, a portland cement for leveling, followed by the Roppe moisture resistant adhesive, and then the 1/8" rubber floor itself.

Reading the GBA site, I'd like to get 1" of XPS in there somewhere. The question is - where do I put it among all these layers?

In Energy efficiency and durability | Asked By Kate Wertime | Apr 11 15
2 Answers

Effectiveness of ductless minisplits for humidity control?

I live on the Texas Gulf Coast. We have to deal with heat and humidity. I live in a two story home not designed with ductwork. There is no easy way to use conventional HVAC. I am considering ductless mini-splits but I don't see how they remove humidity from the house. Please explain.

In General questions | Asked By Lanning | Apr 12 15
1 Answer

Cape Cod Home - condensation on LL floors - mid-May through mid-September

Cape Cod Home - condensation on LL floors - mid may thru mid september... the basement is walk out with windows, slider, so a fair amount of air goes through.

I do understand the floor is colder than the air flow temp. The key piece of info is that there is no insulation under the concrete floor.

The real question.... can a layer of foam be put down over the concrete and then a sleeper floor over that ?? or simply the sleeper floor ? what is the correct way to mitigate that condensation problem on some level.

In GBA Pro help | Asked By PrestigeProperties | Apr 13 15
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