How to Draw a Site Plan for a Building Permit in Sarnia

If you are applying for a residential building permit in City of Sarnia, the site plan is the drawing that shows where the work will sit on your lot. City of Sarnia's permit guides ask for site plans for projects such as detached accessory buildings, decks, and above ground pools, with enough property measurements, structure locations, dimensions, septic information, and setbacks for the building review.

This guide explains how to draw a site plan for a residential building permit in City of Sarnia, what to include for common homeowner projects, and how to prepare a clear hand-drawn or survey-based drawing.

New to site plans?

If this is your first one, read what a site plan is and why you need one in Ontario first. It covers how a site plan differs from a survey, a floor plan and an elevation, what setbacks and easements actually mean, and why municipalities ask for the drawing at all. Then come back here for what City of Sarnia expects on top of that.

One local wrinkle to keep in mind while you read that: City of Sarnia measures setbacks by yard, asking for front, side, and rear distances from the lot lines, and it also wants distances to septic components on properties that have a septic system.

Do you need a site plan?

You should expect to provide a site plan when the City of Sarnia permit package involves a new exterior structure or a project with a specific location on the lot. The City's own guides identify site plans for detached accessory buildings, decks, and above-ground pools:

• Residential deck design guide (PDF)
• Accessory buildings guide (PDF)
• Swimming pool building application (PDF)

For a shed, garage, gazebo, sun shelter, or similar accessory building, the site plan needs to show the property, the dwelling, other buildings, and the proposed accessory building location. For a deck, the drawing needs enough context to show the proposed deck in relation to property lines, structures, and septic components. For an above ground pool, City of Sarnia asks for the proposed pool, the pool fence enclosure and gate, adjacent buildings, septic system information, and setbacks.

Create a site plan for free using HomeCat that gets your building permit approved in City of Sarnia. Get started

Site plan requirements for residential building permits in City of Sarnia

A useful City of Sarnia site plan should be legible, scaled or clearly dimensioned, and focused on the review questions for your project. Include:

• Property measurements or lot dimensions
• The dwelling location
• Existing building locations and measurements
• Any other building locations and measurements
• The proposed garage, shed, gazebo, sun shelter, deck, above ground pool, or pool fence enclosure
• The size of the proposed work
• Front, side, and rear setbacks from lot lines
• Distances from the proposed deck or pool to existing structures
• Septic system location when it applies to the property
• The pool fence enclosure and gate location for an above ground pool
• Labels that distinguish existing items from proposed items

Detached accessory buildings

For a detached garage, shed, gazebo, sun shelter, or similar accessory building, draw the full lot and show the dwelling first. Add existing buildings and structures, then draw the proposed accessory building in its intended location.

Write the proposed building size directly on the drawing. Add the front, side, and rear setbacks from the proposed structure to the lot lines. If another building is close to the proposed location, include that building and the spacing between the two so the reviewer can understand the site layout.

City of Sarnia provides this accessory building site plan example:

Accessory site plan example in City of Sarnia

Decks

For a deck, show the property lines, the dwelling, all existing structures that matter to the project, and the septic system location if the property has one. Draw the proposed deck against the house or in the intended location, label it as proposed, and add its dimensions.

Add the distances from the proposed deck to all relevant structures, septic components, and property lines. If stairs, landings, or a change in deck shape affect the footprint, draw those parts as well so the site plan matches the rest of the deck permit drawings.

Above ground pools

For an above ground pool, start with the lot dimensions, dwelling, other buildings, and septic system location. Add the proposed swimming pool, the proposed pool fence enclosure, and the gate location.

Write the pool size on the drawing and show the setbacks from the proposed swimming pool to adjacent buildings and to the pool fence enclosure. City of Sarnia allows pool site plans to be drawn by hand, but they should be legible and drawn to scale.

How to draw your City of Sarnia site plan

The quickest route is to create a site plan with HomeCat — walk your property with your phone and get a permit-ready drawing back, free.

If you would rather draw it yourself, our DIY guide to drawing a site plan in Ontario covers all three methods step by step: from a survey, from a Google Maps screenshot, or by hand.

City of Sarnia does not require a survey. The City's swimming pool building application says outright that site plans may be drawn by hand as long as they are legible and drawn to scale, so the by-hand method is a legitimate route for a simple accessory building, deck, or pool application when you have reliable measurements. If a boundary or dimension is approximate, label it as approximate rather than presenting it as exact.

If you do have a survey, use it — it makes the property lines, building locations, and setbacks far more reliable. If you do not, check your closing documents first, then ask your lawyer, closing agent, title insurer, or mortgage company. City of Sarnia also handles access-to-information requests under MFIPPA through its Freedom of Information process, including requests connected to building permits. Our guide to getting a property survey in Ontario covers the cheaper options before paying for a new one.

Whichever method you use, label the front, side, and rear lot lines explicitly — City of Sarnia's setbacks are stated by yard, and the reviewer should not have to work out which side of the lot is the front. If the property has a septic system, show its location and the distance from the proposed deck, pool, or accessory building to the septic components.

Create a site plan for free using HomeCat that gets your building permit approved in City of Sarnia. Get started

Site plan examples for permit for City of Sarnia

For City of Sarnia, a strong site plan example is simple, readable, and measurement-heavy. The accessory building example shows the kind of information homeowners should aim to provide: the property outline, dwelling, proposed accessory building, existing structures, and setbacks.

For a deck, the same idea applies, but the drawing should focus on the proposed deck's relationship to the house, structures, septic system, and property lines. For an above ground pool, the site plan should make the pool, pool fence enclosure, gate, adjacent buildings, and septic location easy to identify.

Your drawing does not need to look like a professional architectural sheet for every small project. It needs to be legible, drawn to scale when required, labeled, and specific enough for City of Sarnia to verify the proposed location.

Common site plan mistakes that delay your building permit in City of Sarnia

Missing property measurements or lot dimensions

Do not draw only the house and the proposed work. Include the property measurements or lot dimensions so City of Sarnia can understand the available space and review the setbacks.

Missing front, side, and rear setbacks

City of Sarnia's accessory building guide asks for front, side, and rear setbacks from lot lines. Write those measurements on the drawing, especially for sheds, garages, gazebos, sun shelters, decks, pools, and fence enclosures.

Leaving out existing buildings or septic information

Show the dwelling and other buildings on the lot. For decks and pools, include the septic system location when it applies. Missing septic or existing-structure information can make the reviewer ask for a revised site plan.

Not enough detail about the proposed work

Label the proposed structure or work area and write its size. A rectangle without dimensions does not tell the reviewer whether it is a shed, garage, deck, pool, or fence enclosure. Keep the site plan consistent with the rest of the permit drawings and application forms.

Frequently asked questions about site plans

Can homeowners prepare and submit their own drawings in City of Sarnia?

Yes. In Ontario, homeowners can generally prepare drawings for a house they own because the Ontario Building Code exempts design work for "a house owned by the person" from the usual designer qualification requirements under Division C, Article 3.2.5.1.(3)(b)(i). City of Sarnia can still require drawings that are legible, scaled or dimensioned, and complete enough for permit review.

What if City of Sarnia asks me to fill out a Schedule 1: Designer Information form?

For homeowner-prepared drawings in Ontario, select House for the design activities and describe the project, such as "deck," "shed," "detached garage," "gazebo," "sun shelter," or "above ground pool."

Under the designer declaration, choose the option stating that the design work is exempt from the registration and qualification requirements of the Building Code. For the basis of exemption, enter Homeowner.

Where can I get a legal property survey in City of Sarnia?

Start with the records from when you bought the property. Check your closing documents and ask your lawyer, closing agent, title insurer, or mortgage company. If you need to request municipal records, City of Sarnia accepts Freedom of Information requests through its access-to-information process, including requests connected to building permits.

Read our Ontario ultimate guide for getting a property survey before ordering a new survey.

Does my survey need to be recent?

For many residential permit drawings in Ontario, an older survey by a licensed Ontario Land Surveyor can still be useful if it accurately shows the property lines and base property information. Update the site plan to show current buildings, removed structures, new structures, septic information, and the proposed work so the drawing reflects the property as it exists today.

What if City of Sarnia rejects my site plan?

Read the review comments as a checklist. Add the missing property measurements, lot dimensions, dwelling location, existing building measurements, proposed work size, front, side, or rear setbacks, septic system location, pool fence enclosure, gate location, or distances to adjacent buildings.

When you resubmit, make the revisions easy to find and keep the site plan consistent with the permit application, deck drawings, pool application, accessory building guide, or other documents in the package.

Conclusion

A good beginner site plan for City of Sarnia is clear, measured, and focused on the proposed location. Show the property, dwelling, existing structures, proposed work, septic information when it applies, and the dimensions and setbacks that matter for your residential building permit.

Create a site plan for free using HomeCat that gets your building permit approved in City of Sarnia. Get started