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Area of column footing when joist span exceeding 4.9 m


Registered User
Apr 21, 2022
--------------------------------------------------------------------------------------------------------------------------------- Basic Footing Widths and Areas
(2) Where the supported joist span exceeds 4.9 m in buildings with light wood frame walls, floors and roofs, footing
widths shall be determined according to,
(a) Section 4.2., or
(b) the following formula:
W = w • [ Σ sjs / (storeys • 4.9)]


(3) Where a foundation rests on gravel, sand or silt in which the water table level is less than the width of the footings
below the bearing surface,
(b) the footing area for columns shall be not less than twice the area required by Sentences (1) and (2), and

1. Is footing area of columns permitted to use the formula of (2)(b) to calculate when supported joist span exceeding 4.9 m? (Note: references for footing area)

2. In reality, columns would support beams and beams support joists, while the beam span would be the column spacing as in the table, is this understanding correct?


Aug 12, 2021
Clayton NY
Can't tell without more code text but seems to be about basic spread footings supporting (typically) a stem wall, sill plate, and joists bearing directly on the sill plate. 1. Don't know for longer joist spans but 4.9 meters bearing is a 32' joist, uncommonly long for a dwelling typical of this construction. 2. I sense to that column loads and their footers at elsewhere in the code.

Is this code available for free viewing on online?
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