Know what matters
Know what applies to your project.
Check the conditions below before you finalize the scope. Every answer connects to an official source.
London lists re-shingling as work that does not require a building permit. Roof extensions or alterations that increase height or change slope require a permit.
Source · City of London
Before you apply for a building permit · Residential permit triggers, exemptions and review timelines
Verified Oct 1, 2026Open official sourceMake a start
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Your next steps.
- Record the scope: existing and proposed roofing material and weight.
- Gather: any changes to framing, roof slope or roof height.
- Compare the exact scope with this municipal statement: London lists re-shingling as work that does not require a building permit. Roof extensions or alterations that increase height or change slope require a permit.
- Ask which documents, fees and inspections apply to this exact scope; keep the written response with the project records.
- Resolve approvals before committing to a construction start date.
Trace the evidence
Official sources behind this guide.
These are the source documents linked in the rules above. Check the municipal authority for current requirements before submitting a project.
- City of London
Before you apply for a building permit · Residential permit triggers, exemptions and review timelines
Source verified Oct 1, 2026
A little more clarity
Common questions.
What should I ask before starting a roof replacement project?
Is this a material-only replacement, or do the structural or material changes need approval?
Does this approve my property-specific project?
No. The published general guidance is verified; zoning, exact scope and other approvals still need to be resolved for your property.
Do you need a permit for roof replacement in London?
London lists re-shingling as work that does not require a building permit. Roof extensions or alterations that increase height or change slope require a permit.
Same project, different city
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