January 15, 2003
BCAB #1576
Re: Foundation Wall Height Above Finished Ground, Sentences 9.15.4.1.(1) and 9.15.4.3.(1)
Project Description
The building in question has a covered "porch," about 8 meters long and 1.5 meters deep, along the front exterior wall of a house. The floor of the porch is concrete poured over compacted fill with its floor level near the same as the interior floor of the house. The front of the porch terminates over a 200 mm foundation wall which also supports the roof system of the house through 150 mm X 150 mm columns. The rear of the "porch" terminates at the front wall of the house, which is supported on a 200 mm foundation wall. This foundation wall encloses an 8 foot high basement.
(Contact the Building and Safety Standards Branch for a description and sketch of the subject area)
Reason for Appeal
Sentence 9.15.4.3.(1) requires exterior foundation walls to extend 150 mm above finished ground level. Sentence 9.15.4.1.(1) limits the height of finished ground above the basement floor to between 2.15 m and 2.30 meters, depending upon the strength of the concrete, where a 200 mm foundation wall is laterally supported at the top.
Appellant’s Position
For the purpose of Sentence 9.15.4.3.(1), the appellant contends that "finished ground level" is the ground level adjacent the exterior foundation wall at the front of the covered porch area.
The appellant does not consider the "porch" slab as part of finished ground and should not be included in the calculation when determining the difference in elevation between the basement floor and finished ground.
Building Official's Position
The Building Official contends the basement foundation wall exceeds the height permitted by Sentence 9.15.4.1.(1) and considers the elevation of the concrete porch slab to be finished ground when determining the height of this wall. Further, the Building Official considers the basement foundation wall to be the exterior foundation wall in the application of Sentence 9.15.4.3.(1).
Appeal Board Decision #1576
It is the determination of the Board that the basement foundation wall exceeds the prescriptive limits stated in Sentence 9.15.4.1.(1) (Table 9.15.4.1), therefore the wall must be designed in conformance with Part 4 as required by Sentence 9.4.1.1.(1).
As the Board considers the basement wall to be an exterior foundation wall the requirements of Sentence 9.15.4.3.(1) apply. Further, for the purpose of this requirement, the Board considers the top of the "porch slab" to be the finished ground. Alternatives to the prescriptive requirements may be considered by applying Section 2.5 "Equivalents"
George Humphrey, Chair