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1 Answer

Can I remove my collar ties in my Cape Cod attic or at least remove every other one?

I have a quick question about my collar ties that are located on each rafter in my cape cod 1.5 story attic. The collar ties (1.5 in by 5 in) are positioned at 7.5 feet high ( at the bottom of each collar tie) with the apex of roof at 10 foot. The rafters are 2x6 and go all the way down to the eaves. Are these collar ties structural or can I take them out or at very least every other one? Even after taking out every other one I would still have them about every 2.5 feet. Currently they are spaced a tad over a feet apart.

In Building Code Questions | Asked By Michael H. | Feb 6 13
3 Answers

Using hardwood or bamboo flooring planks on walls

I live in climate zone 4a of the United states. I'm having a 3 season sunroom built and would like to cover the walls with hardwood or bamboo flooring planks horizontally over half inch osb or plywood. I have been told that this is doable. My concern is that this room will be unheated. CAN I DO IT????

In General questions | Asked By Wendell Richardson | Feb 5 13
18 Answers

Asphalt shingles, synthetic underlayment, closed-cell foam and buckled shingles

I am just finishing up a home.The roof was installed about 1 year ago.

I have 6-8 inches of closed cell foam on the attic side of osb roof decking(unvented attic). The roofer used synthetic underlayment(grip rite shinglelayment) on top of the osb and then certaintweed landmark asphalt shingles on top of the underlayment.There are garage sections of my roof that do not have closed cell foam used and a more tradional vented attic.

In General questions | Asked By edward lord | Nov 28 12
3 Answers

Insulated Wood Headers

Question about the level of “perfection” that is required for insulating wood headers: Climate Zone 4A, 2x6 exterior walls, and I detailed the headers with the required number of vertical 2x10s (i.e., I didn’t do triple 2x10s in non-load bearing walls). The 2x10s are held to the outside face of the wall. For a single 2x10 condition (~4” void) the insulator was able to dense pack cellulose. For a double 2x10 condition (~2.25” void), I installed 2” of XPS with a half inch gap and foamed in the edges. For a triple 2x10 condition (~.75” void), I caulked the edges for air sealing.

In General questions | Asked By David Baca | Feb 5 13
7 Answers

Insulating 140 yr. old balloon framed building w/ brick facade

I am trying to come to grips insulating and air sealing a 3 story 140 yr old brick facade building with wood balloon framing.
The order of materials from the exterior is brick, 2"x5" studs 1' on center, 1" sheathing (widths very from 6" to 30"), vertical lath on top of the studs, horizontal lath (spaced for plaster key ways) and plaster which has been removed. There is no insulation currently in the building and the brick ties are two cut nails tacked into the exterior side of the studs and imbedded in the brick mortar joint.

In Energy efficiency and durability | Asked By George Ewbank | Jan 31 13
0 Answers

Encapusulating fiberglass insulation

Hi All,

Need some advice please.

Trying to figure out what insulation to use on a new build.

ICF walls R40, R20 Slab, looking for R60 roof.

My roof is a skillion/shed style 20" thick I-joists with metal on top. There will be no holes in the drywall other than electrical boxes (no can lights). The roof is dead square, no valleys, or peaks.

In Energy efficiency and durability | Asked By Darren Warmuth | Feb 5 13
10 Answers

Two vapour retarders back to back

Hi everyone,
The plan on our project was to use our 5/8" t+g osb as the air+vapour retarder. it has acoustic sealant on all panel edges and where it touches all framing members. the bc building code does not explicitly state panels can be used as the vapour retarder but it does allow for vapour retarding paint. that said, the inspector reallllllly doesn't like the idea of not using poly. the ceiling has an uninsulated 2x8 service core with the t+g on the exterior side. we plan to insulate to about r80 with fibreglass or cellulose.

In General questions | Asked By erik olofsson | Jan 30 13
2 Answers

Where is mold-resistant drywall necessary in a daylight basement?

I am confused about where it is necessary to use mold-resistant drywall. Half of my basement is underground and is poured concrete, the other half is regular walls with 2X6 framed walls, blown cellulose insulation, OSB sheathing, Tyvek, and Hardie panel siding. Is mold resistant drywall needed on all walls in the basement, or just on the walls that are below grade? The below grade walls are insulated with 3/4 inch XPS and strapped with vertical treated 1X4s.

In General questions | Asked By Robert Sanders Jr | Jan 31 13
2 Answers

Concrete over above-grade rubble foundation

I was visiting a home the other day, primarily in search of no/low cost energy improvement opportunities, when the customer asked about insulating his rubble foundation. I recommended ccSPF of course with a poly lining on the floor and up the sides of the walls to create an air and water tight assembly.

In Green building techniques | Asked By Mike LaCrosse | Feb 4 13
1 Answer

Wall insulation/ventilation region 6 A

I am wondering if anyone has come up with a formual that calculates the minimum stand off for a canadian rain curtain that take into account the exterior wall insualating materials, r value, max. wall ht and building location/elevation?

I am also trying to locate some information relating to any benifits to reduced energy consuption a raincurtain might add. Feedback from my clients has been all over the place on the retoros we have completed and they most likely also include upgrades to the roof & attic insulation at the same time



In GBA Pro help | Asked By Matt BLANC | Feb 2 13
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