Do you need a permit for a shed in Dorval?

The rules, in short

Rules from Chapter 7 (Residential neighbourhood zones H) of By-law RCM-60A-2015. The consolidation does not print section numbers, so sections are cited by their heading, except sections 336 and 356, which the text names. Setbacks come from each zone's grid of uses and standards.

• Garden shed: not allowed in the front yard; one per lot; 0.61 m from the side and rear lines, 1.5 m from the house; one storey, at most 3.7 m and 19 m². (ch. 7, s. 356, table, row 13)
• Detached garage or carport: one only; not in the front setback; 1.5 m from the side and rear lines; one storey and 4.5 m; at most 56 m². (ch. 7, div. 5, subdiv. 2, "Detached garage and carport")
• An accessory building cannot contain a dwelling unit. (ch. 7, div. 1, "Additional uses, structures, equipment and accessory uses", 3°)
• A building permit is required for a shed, a garage or a permanent carport; all accessory buildings together may not exceed 10% of the lot. (City page on permit and certificate applications (sheds, garages and permanent carports))

Summary by Radar Foncier, in our own words: the official French text of the by-law, linked above, prevails.

Applying in Dorval

• Processing time: 30 working days after a complete application is filed
• Urban planning department: 514 633-4084
• Permits on the municipality's website