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0 Answers

New hybrid termite emerges in Florida

Read an article about scientists at the University of Florida discovering a new termite which is a hybrid species formed from the Asian termite and the Formosan subterranean termite. These two non-native species are now mating and have created a "super" termite which grows faster, eats more wood and can handle colder climates.

Not good news since termites already damage 600,000 homes per year in the US and we spend $5 BILLION on damage repair and treatments.

In Energy efficiency and durability | Asked By Peter L | Mar 29 15
6 Answers

I need assistance with window/door install with 4" foam

I am looking for some direction on installing windows and doors. I have 4" exterior EPS on a 2x6 walls

The current plan is to build 5/8" plywood boxes (I believe they are called Dewey boxes) to get the nail fin of the window to the same plane as the furring strips that the foam and the siding will be attached to.
I am sure its been covered but searching Dewey box got me 0 results so I wonder if someone could point me in the right direction?

Thanks
Tim (Kenora ON Canada zone 7)

In Green building techniques | Asked By tim brown | Mar 28 15
2 Answers

How to insulate a condo concrete floor?

My daughter bought a condo in a highrise concrete structure. This past winter the floors have been cold even though the floor is the ceiling of a heated garage (55F) below. The shower floor next to an outer wall was 37F, outside temp was 12F. How can we insulate the shower and bathroom floor? The floor is ceramic tile.
We may even consider insulating the entire condo.

In Energy efficiency and durability | Asked By NORM DITTER | Mar 29 15
13 Answers

Non-typical insulation of barn / garage

I live in Interior Alaska Zone 7/8. I have a rather large barn pole barn that needs to be insulated so it can be heated. Since it is rural there is no code but i want to ensure that i do not do something that damages or ruins the building over the long term with that said money is not unlimited. The space is intended to be heated to just above freezing 35 to 40 typical with the ability to warm even more during use. Not a business just personal use during the week.

Barn size is 50x60 with 14 foot walls.

In Energy efficiency and durability | Asked By James Williamson | Mar 22 15
11 Answers

Insulating scissor truss

Hi, I am building my first house, what a project that has turned out to be but that's for another day. Anyways, our great room has scissor trusses for a nice pitched ceiling. I would like to have at least 24" of insulation to keep things nice and toasty in the winter. There is a 4' overhang outside on either end. I nailed a 24" high plywood leaving a vent space above where the red is on the layout. My question is what material and how to go about it. To use the high density cellulose is has to be contained by some mesh? Any input appreciated.

In Energy efficiency and durability | Asked By Tom Smith | Jul 19 14
3 Answers

JM Spider overhead

I was planning on using JM Spider on the underside of my structural roof deck. (There is a layer of peel and stick and 5.5" of polyiso foam board above the deck so no worries about vapor permeable insulation inside). The installer is having problems with getting the Spider to stick overhead. The installer says JM changed the fiber recently and they are having difficulties with some wall installations too. While they are working with JM, I was wondering:

Has anyone here had JM Spider installed overhead recently?

In General questions | Asked By Eric West | Mar 27 15
1 Answer

XPS as interior insulation on a plank wall

Architect's plan calls for 2" of "rigid" on interior side of a plank wall in Williamstown Ma (zone 5). Even if we tape the seams and air seal as best as possible, I am still concerned that moist air will get to the back of the planks and create moisture issues. The exterior is not being touched and I assume that there is no kind of air space between the planks and the siding. The space will be air conditioned in the summers and the 2" of xps (class II vapor retarder) gives me some drying capacity to the inside. Is that enough? How risky is the assembly?

In Energy efficiency and durability | Asked By Joseph Carry | Mar 27 15
8 Answers

Porch posts

We are building a wrap around porch that extends 6'. Since we know, because of code we have to use 6x6 for the posts for the deck, I have question about the posts that supper the roof.

One way is to use the same 6x6 and extend it from footer to header. We think that since these posts will be 6' apart going around the porch it might seem a bit too bulky.

Does code allow you to replace 6x6 posts with a PVC reinforced porch posts (they are turned and look like traditional porch posts)? Or do we have to stick with 6x6 lumber?

In Building Code Questions | Asked By Matt Cibula | Mar 25 15
9 Answers

Dryer vent in air-tight Passive House

I am building a house in the Seattle area to Passive House standards. After spending countless hours sealing every crack, seam and penetration to achieve under 0.6 ACH, creating a 4 inch diameter hole in my air barrier pains me. I've looked into condensing dryers that are used in some European Passive Houses, but they seam to take much longer to dry and use lots of water. Since I will be installing a vented dryer (unless someone can come up with another solution), are there ways to make the dryer wall vent more air-tight when the dryer is not in use?

In PassivHaus | Asked By Gerald Blycker | Nov 21 14
3 Answers

Manual J - Calcs - Mini Splits

Zone 4B - 3,300 sqft - 2 story - R10/R25/R60 with R8 windows - open floor plan design

The calcs came in at 3.25 tons heating/cooling. Two ductless minis per floor:
3 - 9,000 Btu Mitsubishi Hyper Heat Pumps - 26 SEER - 10.5 HSPF
1 - 12,000 Btu Mitsubishi Hyper Heat Pump - 26 SEER 10.5 HSPF

$12,000 installed (P&L) for all units - 10 year warranty

In Mechanicals | Asked By Peter L | Mar 26 15
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