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4 Answers

Exterior foam and fluffy inside

Building a new house in climate zone #5 and was planning on 5" of exterior foam and R30 on the inside of a flat, non-vented roof. The two story part is still good for this set-up but the one story portion - garage and heated workshop is now messed up as the EIFS installer only allowed for 2" of foam on the garage and workshop roof. I spoke to the EIFS installer and he said it would be quite a job to correct and not his fault as the builder did not tell him 5" of foam.

In Energy efficiency and durability | Asked By matt watson | Apr 16 17
2 Answers

Insulating a "pole building" / garage using nail base insulation panels

Greetings,

In Energy efficiency and durability | Asked By Marco Marra | Apr 16 17
0 Answers

HTP Crossover Wall or Phoenix LD?

I'm looking at my options for a combination water/space heating appliance. I'm liking the look of two HTP units that are completely different in operation, the Crossover Wall and Phoenix LD.

The Crossover Wall is a combination on-demand/tank heater with a small tank, 10-1 turndown and either 150k or 199k BTU ratings. The Phoenix Light Duty is a conventional tank-type water heater with condensing burners, 3-1 turndown and 76k BTU input. Both are very efficient, though feedback and reviews are limited. The Phoenix LD has some positive reviews, but relatively few.

In Mechanicals | Asked By Lance Peters | Apr 17 17
2 Answers

Spray Foam Attic: Is blocking at the eaves required?

Closed-cell attic spray foam, climate 4A, balloon frame 1924 house, dense pack cellulose already in walls. As I'm trying to prep the attic prior to the insulation, I am also trying to educate myself on some of the specifics so I will be able to get my preferences spelled out in the eventual contract. Often times details are left out and left up to the contractor. Part of the steepness of the learning curve is that if you've never studied wood-framing or observed your house's framing up close it's hard to visualize how things are actually laid out.

In Energy efficiency and durability | Asked By David Goldman | Apr 14 17
4 Answers

Opinions on a wall system

Hello. I would appreciate any thoughtful opinions on a wall system I am looking into.

In Green building techniques | Asked By David Sol | Apr 16 17
18 Answers

DensGlass sheathing and rainscreen materials

Martin,

Other than not holding siding fasteners, what are the downsides of using Densglass instead of plywood sheathing? A (modest) price difference? Is taped Densglass less of an air barrier than taped plywood?

In Green products and materials | Asked By Domenico Perrella | Apr 11 17
7 Answers

Patio insulation

I live in Florida and enjoy sitting outside on my roofed patio. However, during the summer the heat radiating through the roof is intense. Do you have a suggestion about the best way to slow or stop this radiant heat coming through the ceiling of the patio?

In General questions | Asked By Bob Ross | Jan 30 16
3 Answers

Insulating old 2x4 walls with rigid insulation

Our home is located in western Maryland, (zone 4?) and was commercially built to increase profits without regard as to results. It is a 2800 sq. ft. brick faced story and a half salt box style with full basement and set back into a hill. Foundation is essentially a monolithic pad poured without benefit of steel reinforcement of any kind with extra depth along the rear ground level side. Walls are 2 x 4s with fibreglass insulation stapled inside the stud bays. Front roof 2 x 10s have 6" fibreglass as do the upper bedroom ceiling joists.

In General questions | Asked By user-6818892 | Apr 13 17
7 Answers

Best method for air sealing an existing tongue-and-groove (wood) ceiling? Sheetrock is out.

The Home is located in Zone 4 NC. Question #1 Any problems using closed cell spray foam on any

large cracks , in attic at ceiling plane. Then using blown in cellulose ?

Question # 2

Any best method for securing tongue and groove ceiling to prevent cellulose from pushing down ceiling ? Netting etc.

Question # 3

Thought of using Reclaimed Commercial Roofing foam board Fiberglass faced , using cut and cobble

at attic joist bays. Leaving small air gap from tongue and groove ceiling. My thought was it would

In General questions | Asked By Greenconfusion | Apr 13 17
9 Answers

Slab to foundation wall: Air Barrier and capillary break detail with interior rigid foam

We’re planning on insulating our basement walls with 2 inches of Thermax (foil-faced polyiso) rigid foam, installed with adhesive on the interior of the wall. We’ll also have 2 inches of XPS beneath the 4 inch slab, and would have these different types of foam connect right on top of the footer, similar to the detail shown at:

http://www.greenbuildingadvisor.com/cad/detail/insulated-basement-poured...

In Green building techniques | Asked By William Costello | Apr 12 17
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