BCAB #1114 - Finished Ground Level

January 23, 1990

BCAB #1114

Re: Finished Ground Level

With reference to your letter of November 21, 1989, regarding the application of Article 9.28.2.2. From the information received it seems that you have vinyl siding, so the application of Article 9.28.2.2. is eliminated. However, sheathing forms part of the framing, so would be affected by Article 9.23.2.3.

For the situation under review, Article 9.15.4.3. requires that the exterior foundation walls extend not less than 150 mm above finished ground level; we do not consider the fact that a concrete sidewalk is involved to be relevant, the top of the concrete is the top of the finished ground level for this purpose. Under Article 9.23.2.3., if the wood framing has not been pressure treated with preservative and is less than 150 mm above finished ground level, then it must be separated from the concrete by a dampproof course.

Your diagram indicates a treated wood plate 6 inches above the concrete sidewalk, it does not state if this plate is pressure treated, and does not mention the sheathing, which is part of the framing. It also shows dampproofing beneath the plate, presumably of the type acceptable under the Code, but does not say whether this dampproofing extends beneath the bottom of the wall sheathing. If, in fact, the dampproofing is the full width of the wall framing, then you comply with Article 9.23.2.3., without the need for any other measures such as a protective flashing. If your framing is 150 mm or more above the sidewalk surface, then the Code does not even require dampproofing. We do not understand the reference to a clearance of 200 mm, the Code uses a minimum of 150 mm.

At this point we are unable to be more specific, without additional information, but the adequacy of your installation should be easily assessed from the explanations we have given.

J.C. Currie, Chair