BuildRules/Mississauga/Home addition

Mississauga project guide

What do you need for a home addition permit in Mississauga?

Prepare a Mississauga home addition permit with the required site plan, elevations, mechanical forms and official City submission requirements.

1 min readReviewed Oct 1, 2026

The short answerConditional

A residential addition uses a dedicated building permit submission package with site, architectural and supporting documentation.

Mississauga’s addition checklist requires the existing and proposed work to be shown clearly and to scale, including a detailed site plan and elevations.

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Know what matters

What changes the answer.

Start with these conditions. The official reference is attached to each one.

Permit packageDedicated addition submission requiredConditional

Mississauga publishes a project-specific building permit checklist for residential additions.

Official sourceCity of MississaugaAddition · Residential addition forms, site plan and drawings

Verified2026-10-01Open proof

Site planRequiredInfo

The site plan includes property information, existing structures, proposed construction and site statistics.

Official sourceCity of MississaugaAddition · Residential addition forms, site plan and drawings

Verified2026-10-01Open proof

ElevationsRequired for each sideInfo

The City asks for existing and proposed work, grade, floor levels, dimensions, windows, doors and roof information.

Official sourceCity of MississaugaAddition · Residential addition forms, site plan and drawings

Verified2026-10-01Open proof

Your preparation checklist

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Applicable Law Form
Schedule 1 Designer Information
Site plan
Floor and roof plans
Elevations and sections
Mechanical and water-service information where applicable

Open the focused permit checklist

Fees and timing

TimelineConfirm the current municipal review stream after the application is accepted as complete.

FeesConfirm the current Mississauga fee schedule for the exact permit class.

Next steps

Check zoning feasibility
Prepare the site and building drawings
Assemble the City forms
Submit the complete addition package through ePlans

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 home addition rules by city

Better decisions, together

Get everyone on the same page.

Send this to your designer or contractor before agreeing on the scope.

Paid research brief

Get a clearer plan before you spend.

Turn the published rules, documents, timing and questions to verify into one project-specific preparation brief.

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See what’s included

Research guidance only. Municipal approval and professional design are separate.

A little help with the next step

Move your home addition 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.

BuildRules principle

Do not confuse “no permit” with “no rules.”

Zoning, overlays, safety rules and other constraints can still apply.

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