Professional Calculators
Technical calculators for designers, architects, and contractors — full compliance tables and detailed calculations, straight from the OBC.
Look up SB-1 climate and seismic data for any Ontario location. Find SB-12 compliance packages for new construction and additions (Zones 1 & 2), and SB-10 thermal requirements for Part 9 non-residential buildings (Div. 5) and Part 3 buildings (Div. 3, climate Zones 5/6/7) — all occupancy types.
Calculate the maximum permitted unprotected opening area for any wall — Part 9 or Part 3. Part 9 covers OBC Tables 9.10.15.4 (residential, business & low-hazard industrial) and 9.10.14.4 (mercantile & medium-hazard industrial). Part 3 covers OBC Section 3.2.3.1 Tables B, C, D, and E — all with bilinear interpolation for limiting distance and exposing building face area.
Find the minimum window area for habitable rooms under OBC Table 9.7.2.3. Enter floor area and room type — bedroom, living room, kitchen, or basement — and get window sizing options, sill height requirements, and electric-lighting exemptions.