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2 Answers

Insulation Against Concrete and AAC Wall

Hi all; with the help of the answers to my previous question (thanks!!) We've attached 3" of XPS and EPS foam against the interior of my foundation walls. We used a combination of glue and screws/washers to hold it against the walls. All told it seems to have worked nicely. Thanks for the suggestions on that one! Now to my next round of questions:

In General questions | Asked By Michael Grundvig | Mar 12 18
8 Answers

Vented over roof on parallel chord truss

I'm about to commence a project and I've got all the details dialed in up to the roof and I'm leaning towards the following.

In Green building techniques | Asked By Will Schebaum | Sep 19 16
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
8 Answers

Zone 5 Envelope Enclosure / Parallel Chord Truss

I'm will be building a home this summer / fall and have started working out the details for my build.

I'm in zone 5, BC, Canada, and intend to build a simple shaped gable end structure with cathedral ceilings. I've located a truss manufacture who can build parallel chord scissor trusses for me that will meet my 20' span without a ridge beam.

In Energy efficiency and durability | Asked By Jeff Pepperdine | Feb 12 15
10 Answers

Raised-heel trusses can be annoying

We installed raised-heel trusses with bottom chord overhangs on our house. The top of the top chord is 20" above our top plate. According to the 2012 International Residential Code for seismic zones or zones designated for winds of 100 mph, raised heel trusses more than 15.25" have to be blocked and braced.

In Green building techniques | Asked By Jimmy Nguyen | Feb 6 16
93 Answers

Explain the correct usage of rigid insulation on the exterior of the building.

Rigid insulation seems like a good choice to add R-value to the whole wall (breaking the thermal bridging, etc) as opposed to just between the studs like most insulation. But isn't it basically impermeable and thus not allowing the wall to breath...not allowing moisture from the inside to exit by diffusion.

In Energy efficiency and durability | Asked By Conrad Welch | Nov 3 09
6 Answers

Mold Remediation

Anyone have mold remediation on a commercial building experience or been/are in the mold remediation industry?

I have a maintenance contract on this building that just started, could smell a strong mildew odor in a unit on the top floor north side of the building when completing a PO. Was doing top floor work in the south side of the building no odor. Slight odor in hall at the midpoint of the building top floor. It was unseasonably warm that day, mid 40's high temp.

In General questions | Asked By T Carlson | Mar 5 18
5 Answers

Can a rainscreen become a chimney for fire?

I have a client who is concerned about fire in a rain screen I recently put up to go under siding.
This is a wall of rough cut 1 inch board sheathing covered in typar and taped at all penetrations and seams. The typar is the primary air barrier. The rain screen is 1X3 (3/4 thick) strapping running vertically every 16" oc. The bottom is open and covered with fiberglass mosquito netting and the top is open to the soffit. The soffit is not vented into the attic. I am planning to insulate with dense packed cellulose. The siding will be vertical grain unpainted cedar.

In Green building techniques | Asked By Josh Engle | Oct 5 16
7 Answers

Flashing deck ledger

So my build is getting closer to a go this spring, as plans are wrapping up, I'm trying to get the small details correct, I've learned on this site, these can come back to bite me if not done correctly.

So our house is single storey with a walk-out basement and full wrap around covered porch.
Walls are 2x4 stud 1/2 sheathing taped, 6" polyiso(2 x 3") ,Tyvek, 3/4" furring with vinyl siding , basement is 8" ICF(Logix)
so 13.5 " total width plus 2"x4" stud walls on the interior.

In Green building techniques | Asked By Dave B | Mar 12 18
6 Answers

3rd Party HVAC Design

All - Building a new home in Colorado and I'm torn on what my HVAC design strategy should be. I've had some knowledge of the HVAC industry through a family member which have left a bad taste in my mouth (not saying all are bad!) but this further fractured my trust given my own personal experiences.

So here we are, building a large custom home, and I want to ensure we get things right and I can effectively go out to bid w/ a solid plan.

In Mechanicals | Asked By COCYCLIST | Mar 12 18
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