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2 Answers

Closed-cell spray foam insulation under a sunporch

We installed 2 inches of spray foam closed cell insulation on the underside of a sun porch which is open on a sides underneath. My husband wants to store his riding lawn mower underneath which means he will have to drive it under the porch and start it up under the porch. I understand that this foam is highly flammable. Please advise if this is safe or what we can do to ensure safety of the storage of the riding mower. Thank you.

Denise P

Asked By Denise Phelps | Jul 27 16
3 Answers

Notched I-joist fix

We had a plumber notch our new home's engineered i-joist when installing a tub drain. We were furious but that is besides the point at this time. We are attempting to get it repaired.

Per the building inspector's recommendations, we contacted the joist company. They suggested cutting a 13" section of the damaged part of the joist and heading it off with smaller i-joist sections attached perpendicularly onto the two adjacent i-joists.

Asked By Kara English | Jun 22 16
11 Answers

Poly and Canadian building codes

This comes up quite frequently and I thought it might be useful to lay out what is actually required by the code. My description relies on the BC Building Code, but I am fairly confident it applies to all provinces that have based their codes on the NBC.

The code requires all building assemblies to include an air barrier and a vapour barrier.

The air barrier can consist of a variety of sheet or panels materials. It can be located anywhere in the assembly. That is the inner, intermediate or outside surfaces of the assembly (

Asked By Malcolm Taylor | Apr 4 16
9 Answers

Slab insulation - do I understand the code requirements?

Question about slab insulation. The current slab has zero insulation on each side. That was no issue until now because it always an unheated garage. The slab is just that, a slab. No footing, no drainage.

Living in zone 5A and using the table Martin gave me in another thread I conclude I need:
- R-10 on the edge. --> 2.38" EPS or XPS*
- R-30 on top of the floor indoor. --> 7.14" EPS or XPS*

*= I use R4.2 for both EPS and XPS because I will use reclaimed foam. From what's I've understood XPS outgasses and it's R-value drops to that of EPS over time.

Asked By Tony Tibbar | Jun 18 16
2 Answers

Do basement stairs have to be enclosed?

Hi all,

Just checking code. I will have a basement, and at the top of the basement stairs I will have a door. Does the staircase down to the basement have to be enclosed, and a door at the bottom of the stairs?

If it matters, I will have engineered I-beam floor joists between the basement and 1st floor, which I understand have a little bit different fire code requirements?

Asked By Clay Whitenack | May 9 16
1 Answer

Townhouse common wall upgrades

I had a kitchen fire in my Gaithersburg, Maryland townhouse (about 20 miles north of Washington DC). The insurance is going to pay to have the walls on the first floor removed and have the insulation replaced. The townhouse was built as part of a quad in 1986, with the main wall facing south, and east and west walls connected to neighbors, and half of my northern wall is connected to my neighbor behind me (the other half faces the central atrium).

Asked By Carl Fosler | May 5 16
5 Answers

Continuous insulation under slab

Hi all,
I am looking for some advise on the design of our thickened slab for a "pretty good house" in Kenora, Ontario (climate zone 7).
The house will be 32' x 24' with a loft. We are planning for 6" of rigid foam under the heated slab. Our designer and engineer are adament that the rigid cannot be placed under the footings and under the post. They are telling me this is against the Ontario Building Code and that the engineer will not put his stamp on it.
I am wondering if anyone else has come across this in Ontario?

Asked By Adam Smerchanski | May 2 16
1 Answer

Is there a code requirement for residential boiler piping insulation?

Is there a code requirement for residential boiler piping insulation?

If so, what is the R-value for pipes in conditioned space? And unconditioned space?

We live near Baltimore, MD.

Asked By Brantley Gent | Apr 30 16
6 Answers

Ridge Vents - see light?

I was at our new construction home yesterday. It is not yet insulated. I looked up and noticed one small hole where light was coming through. It was at the peak of the roof (runs along the length of the house - it is a ranch). The was no plywood in this area - just synthetic tar paper/shingles could be seen. Our builder said this just where the shingles come together and that no water or anything can get in there. If they put plywood under it, it will wick and rot. He said he could put steel wool there or caulk it but that is not normally what is done. It is normally just left open to vent.

Asked By Carolyn Farrow | Apr 22 16
12 Answers

Addition cement foundation below grade, patio pour?

Hi all,

We just moved in to a home about a year ago so I am still in the process of finding things out (and learning what's terrible and what's not...), but I had a question regarding pouring a patio at grade if the cement block of our foundation is below grade.

Picture attached.

The blue metal is what I assume to be flashing to cover the treated wood from the elements, but you need to go down about 2-3 more inches to reach the end of it where the cement block begins.

Asked By Ryan Lambert | Mar 20 16
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