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2 Answers

Rigid form on interior wall surface

foam insulation on interior side of the wall

In Green building techniques | Asked By Jim Reed | Apr 5 15
3 Answers

Metal Roof Fasteners backing out

Hi Martin Holladay.
I was reading Fine Homebuilding March 2015 and found the article about through fastened metal roofing.
A friend of mine was asking about screws backing out of his roof and I was curious about your opinion about the cause and the fix.
His house is in an area that receives 1-3 feet of snow per winter. Snow usually stays for several weeks.
The metal roof has screws that have backed out.
I was thinking the snow and ice may snag against the screw during melt and movement over several seasons, working the screw out of the roof and structure.

See attached picture.

In Energy efficiency and durability | Asked By Franklin French | Apr 4 15
21 Answers

2/12 cathedral roof replacement


I have a shingled 2/12 roof that needs to be replaced it is a cathedral ceiling. It has no dormers or right angles to it, the size is about 40' by 20'. I am in Vermont so i have serious ice dams which i would like to minimize but heres the catch i am not looking for the 15k to 30k option. I am looking for the most reasonable balanced option under 10k. I have received a few quotes.

1. Strip roof, ice and water shield, architectual shingle ~5500k

In GBA Pro help | Asked By mark kessler | Feb 23 15
1 Answer

How to cover and insulate a floor up on 4' piers or posts to keep the weather out, heat in, and the government men happy

1,236 sq ft., above ground on piers.
One story high, 4 feet off the ground, like a home on the coast, with no walls around the bottom sides.


In Green building techniques | Asked By Jon Uhrick | Apr 3 15
4 Answers

New Construction Insulation

I will be building a 3,600 sq foot house in Salt Lake City. All space will be conditioned. The basement, main, and upstairs are each 1,200 sq feet. The roof has 2x10 rafters, is 6/12, and will be standing seam metal.

I had some energy modeling done and the engineer recommended:

4 inches of EPS under slab
2 inches of XPS on the exterior of the walls
2 inches of Polyiso on the exterior of the walls
4 inches of EPS on top of the roof

In Energy efficiency and durability | Asked By Matt Frieda | Apr 3 15
10 Answers

Replace AC with a heat pump?

I've recently inherited a house in Virginia mountains, climate zone 6, that's been used as a three-season retreat. I want to keep it open in winter. Heating is via coal-guzzling electric baseboards. Conventional AC w/ exchanger in unconditioned 3rd floor attic and flexiducts.
1) Can i replace the AC w/ newest generation heat pump like those used in mini-splits? Local HVAC folks are not familiar w/ the technology, since climate is too cold for conventional heat pumps

In Energy efficiency and durability | Asked By Jerry Knight | Apr 1 15
4 Answers

Does 1x3 strapping reduce thermal bridging?

For those not familiar with the term strapping it is 1x3 boards.
It seems to be a New England thing to install 1x3 perpendicular to ceiling joists prior to installing drywall on the ceiling.
Does this practice significantly reduce thermal bridging of Rafter/ceiling joists in a cathedral ceiling application?

In GBA Pro help | Asked By Dirk Gently | Apr 3 15
6 Answers

Question re furring strips, XP drywall, and finishing basement over 3" of polyiso

I have used recycled roofing polyiso panels (1.5" stuff), staggered them, and going to foam the gaps where I can and use acoustic sealant ("the black death") on gaps too small for foam.

Here is a big question, I want to put furring strips horizontally and just mount drywall over that:
1. Is it OK to just go with furring strips and not build out full 2X3 or 2X4 framing. Wasn't planning to fill the gap with anything between drywall and polyiso

In GBA Pro help | Asked By Apollo S | Mar 23 15
3 Answers

Is it wise to put a product like Drainwrap behind a layer of rigid insulation?

We are getting ready to remove the existing layers of siding from an old (100yrs. +) home that appears to have diagonal board sheathing attached to the studs.

Our intention is to blow cellulose into the stud bays, then cover the board sheathing with Drainwrap integrating the window flashing into this layer, then adding 1" rigid foam with seams taped, and finally adding 1x furring strips and either Hardi or Lp lap siding.

The project is waterfront on a coastal bay in Maryland. The windows in the home are vinyl replacements in original wood frames.

In GBA Pro help | Asked By mike labesky | Apr 1 15
4 Answers

Holding back cellulose

I'm just about done air sealing our attic and getting ready to blow in cellulose. For a few sections I need to make a vertical "wall" of it. One part is where the stairs are. As discussed in another thread part is a flat ceiling, then a vertical slope down to the stair ceiling. I'm going to put fiberglass batts on the vertical sections, but want to blow in cellulose on the flat part. I'm thinking of stapling window screening to the top plate of the actual wall and then staple it to the ridge beam of the house.

In Green products and materials | Asked By Jeremy M | Apr 2 15
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