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3 Answers

Do I need to use concrete screws for plywood over an insulated floor?

i am following your advice on using XPS on concrete basement floor followed by two layers of 1/2 inch plywood. My concrete floor is 15 yrs old will I have trouble with concrete screws in older concrete? Can I just fasten the second layer to the first layer of plywood or can I use adhesive on the first layer or do I need the concrete screws?

In GBA Pro help | Asked By Rita Erskine | Apr 17 15
7 Answers

Cathedral ceiling rebuild techniques?

I have 900 sq feet of cathedral ceiling. Zone 7b. Its 2x10 rafter construction. No venting with recessed lights. Mold and moisture remediation will begin in 2 weeks. I've been doing lots of reading on GBA, I love this site and forum. Right now, the rebuild plan is a sealed ceiling with 4" of 2lb spray foam with the remainder of the rafter bay filled with fiberglass batts. All recessed lights will be removed. I'm considering T&G for the interior finish. Will the T&G change my insulation plan? Am I missing anything?

In Energy efficiency and durability | Asked By Scott Buchanan | Apr 2 15
2 Answers

White pine

Hi, I'm needing to build a large rabbit hutch with an enclosed run, and I have to use white pine because the bunnies will chew on the wood and it is safe for them.

Some areas will be exposed to the weather and I can't paint it. How will white pine hold up unfinished?

In General questions | Asked By Girene | Apr 17 15
1 Answer

Can isocyanurate paper/fiberglass faced insulation board be used on the inside of a wood stud framed wall?

Have old house with 4" cavity in wood framed walls. Exterior has 1" sheathing board with 6" wood shiplap siding over it. Can we put isocyanurate bd on interior of walls to increase the R-factor before we sheetrock top 4' and wood veneer the bottom 5' of the wall. Is their any increased fire hazard or other concerns

In General questions | Asked By Bill OConnor | Apr 17 15
5 Answers

Do I need an interior vapor barrier of some sort?

The house was built in 1991 and is located in SE Mich, Zone 5?

It currently has a wood composite siding, no housewrap, and a mixture of plywood and double foil-faced foamboard (no discernible pattern). The studs are 1x4s. On the inside, it had fiberglass with a plastic vapor barrier. The windows are flangeless wood windows that I plan on keeping and restoring.

In Green building techniques | Asked By Hedy O | Apr 17 15
1 Answer

Anyone using or have opinions of H Windows brand?

We are working on planning a new house in western Wisconsin and have discovered H Windows brand windows made in northern Wisconsin with a dealer less than an hour away. Has anyone used these windows or have any personal knowledge of them? Their specs looked good on paper, I thought. They offer 3 different triple pane glazings. http://www.hwindow.com/wp-content/uploads/2015/04/HWC-Performance-Chart-...
If anyone within a reasonable distance of Menomonie WI has used them (or has a panel built wih SIPs), I'd like to hear their comments.

Thanks for any help or advise.
Jim Erdman

In General questions | Asked By Jim Erdman | Apr 17 15
2 Answers

Photos of site-built ventilation baffles

For an upcoming article on site-built ventilation baffles -- that is, baffles used to create ventilation channels under roof sheathing -- I'm appealing to GBA readers to send me photos of your work.

You can post the photos here, or send them to me by e-mail: martin [at] greenbuildingadvisor [dot] com.

I've heard of builders making these baffles out of rigid foam, cardboard, plywood, and fiberboard. If you have a favorite material, including one I haven't listed, please let me know about it.


In General questions | Asked By Martin Holladay | Apr 16 15
27 Answers

Sizing minisplits for adequate heating & cooling in a cold-climate Passive House

We are building a 2300 square foot Passive House in the midcoast area of Maine and are having trouble choosing and properly sizing our mini splits for both adequate heating and cooling. We live in an area where of course it gets below zero many times during the winter. So we are limited (I think) to the brand of mini-split we can choose from.

In PassivHaus | Asked By CathrynJones | Apr 11 15
9 Answers

Window flashing for new construction

Good morning,
I am getting ready to install windows(aluminum clad) on my new construction and would appreciate help figuring out the flashing details.
The exterior walls are made of gigacrete wall panels. The panels are basically steel studs encased in 8" thick eps. The walls will get a coating of stuccomax(gigacrete'a proprietary exterior coating). There is 3" of eps on the outside of the studs so essentially the windows will be inset a little over 3".

I am attaching a few images so the wall components/window openings can be better understood.

In GBA Pro help | Asked By asim majeed | Apr 6 15
5 Answers

How much of a 2 x 6 plate has to be on the stem wall?

The real question is whether to use 6 in or 8 in blocks for my stem wall. Stem wall is 24 in high, this is slab construction.

The wall is metal, membrane, 1.5 in ISO, 5/8 OSB, 6 in plate, 5/8 drywall, trim.

If I use a 6 in block and line the outside of the ISO with the outside of the block, that puts only about 3.5 in of the plate on the block. Will this work? The good part of this system is that the 3 in of styrene on the inside of the stem wall can be let untouched and thereby give me a good thermal break between the floor and the block.

In GBA Pro help | Asked By Tooger Smith | Apr 16 15
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