BuildRules/London/Windows / doors

London · source-reviewed guidance

Do you need a permit for windows and doors in London?

Prepare a windows and doors project in London: the scope details to gather, questions to resolve and the official municipal starting point.

2 min readLast verified Oct 13, 2026
The short answerConditional

New or enlarged windows and doors require a building permit in London. The City lists same-size replacements among work that does not require a building permit.

The permit statement above comes from the linked municipal guidance. The preparation items below help define your scope; confirm the final application checklist, property constraints and any separate trade approvals with the municipality.

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London / Windows / doors

New or enlarged windows and doors require a building permit in London. The City lists same-size replacements among work that does not require a building permit.

City of London · BuildRules reviewed 2026-10-13

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.

Published municipal guidanceCheck the scope and stated conditionsConditional

New or enlarged windows and doors require a building permit in London. The City lists same-size replacements among work that does not require a building permit.

Source · City of London

Before you apply for a building permit · Residential permit triggers, exemptions and review timelines

Verified Oct 1, 2026Open official source

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Preparation checklist · Reviewed 2026-10-13

Plan ahead

Fees and timing

TimelineNo London project-specific review period has been verified here. Ask when the completeness review begins and which outside approvals must be obtained first.
FeesNo fee has been verified for this project. Ask London which application class applies, which deposits or other approvals are extra, and when payment is due.

From reading to doing

Your next steps.

  1. Record the scope: existing and proposed opening width, height and location.
  2. Gather: wall construction, lintel and structural support changes.
  3. Compare the exact scope with this municipal statement: New or enlarged windows and doors require a building permit in London. The City lists same-size replacements among work that does not require a building permit.
  4. Ask which documents, fees and inspections apply to this exact scope; keep the written response with the project records.
  5. 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 windows and doors project?

Does this scope qualify as a same-opening replacement, or is an opening alteration permit required?

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 windows and doors in London?

New or enlarged windows and doors require a building permit in London. The City lists same-size replacements among work that does not require a building permit.

Know the approval terms

The permit decision can involve more than one rule.

Use these plain-language definitions to understand the conditions above, then check the official source for your municipality.

Building permit

A municipal approval required before certain construction, alteration, demolition or change-of-use work can proceed. The permit review checks the proposed work against the Ontario Building Code, local zoning and other applicable law.

Applicable law

Requirements outside the Ontario Building Code that must be satisfied before a building permit can be issued when the Building Code identifies them as applicable law.

Same project, different city

See how this rule changes across Ontario.

Compare the source-reviewed answer for this project across every municipality BuildRules currently covers.

Compare windows / doors rules by city

When you need a hand

Choose your next step.

Keep preparing on your own, get a research brief, or ask for professional help.

BuildRules / Preparation briefFree report

Before your first contractor quote

Bring the right questions to the conversation.

Collect the published local guidance, documents to prepare and unresolved property questions in one brief you can send or print.

01 Permit and local-rule guidance02 Documents to prepare03 Questions still to verify
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Professional help

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A little help with the next step

Move your windows / doors forward.

Tell us what kind of help you need. We’ll save the request with your project and municipality so a relevant provider can respond if a match is available.

A provider match is not guaranteed. Municipal approval stays with the City.

A provider match is not guaranteed. Municipal approval stays with the City.

Keep exploring

Your next useful question.

A connected project guide or a practical next step, picked for this topic.

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