RENOVATIONS
Interior Renovations in Newmarket
Wall removals, new or larger windows, bathrooms and basement finishing in existing homes.
◆ Newmarket homes and renovations
Newmarket Building Permit Services for Second Units, Additions and Decks
In Newmarket, a building permit for an addition, a deck or a basement unit starts with zoning rather than drawings: the Town asks for a Zoning Preliminary Review before most house applications reach its Development Portal. After that, the local details that shape a file are the registration every second unit needs, a parking rule that often decides whether a unit fits, the 20 cm private tree threshold and the Lake Simcoe Region Conservation Authority’s regulated areas.
Two Additional Units, Three Parking Spaces
Newmarket allows up to two additional residential units on a lot with a detached house, semi, link house or townhouse, so the limit is three homes. By-law 2026-10, enacted on March 30, 2026, lets one of those two be a detached unit in the side or rear yard; the alternative is two units inside the house.
Two Town rules settle most second-unit files before the Building Code does:
- Parking. Each additional unit needs one exterior space on top of the two required for the main house, so a house with a basement unit needs three. The spaces must fit within the permitted driveway width between the garage and the curb, and a space inside the garage does not count.
- Registration. Every additional unit in Newmarket has had to be registered since 2013, under By-law 2013-13. A new unit is registered after the final building inspection, with an ESA compliance report for both units and a sketch of the parking area.
The same permit stream covers basement units, additions, decks and new houses, and the residential building permits page sets out what each of those projects involves.
◆ Before the drawings
Zoning Preliminary Review and the Letter After Your Zone
Most Newmarket houses are zoned under By-law 2010-40. Properties in the urban centres along Yonge Street and Davis Drive fall under By-law 2019-06, and lots in the Oak Ridges Moraine area are handled separately by the Planning Department. The suffix after the zone symbol, the D in R1-D, sets the setbacks, height and driveway width, and a number after it, as in R1-D-119, points to a site-specific exception in Section 8.
A Zoning Preliminary Review is required before the permit application for an addition, an additional unit, a deck, shed, pavilion or gazebo, a demolition or a new building. The Town aims to answer within five business days. If the review finds a shortfall, the route is a minor variance at the Committee of Adjustment, where 2026 fees start at $1,495.40 before HST.
Garden suites follow the new detached-unit limits. A one-storey unit can reach the lesser of 10% of the lot area or 75 m², and a two-storey unit or one above a garage the lesser of 10% or 100 m². Side and rear setbacks are 1.8 m for one storey and 2.4 m for two, the unit stays 3.0 m from the house, and its entrance can be no more than 60 m from the curb along the path of travel.
Private Trees, Conservation Areas and Lower Main Street
A few Newmarket approvals come from offices other than Building Services, and they are easier to schedule before the permit drawings are final.
Private trees. Removing a tree 20 cm or more in diameter, measured 1.4 m above the ground, needs a permit. The 2026 administration fee is $100 for one tree, plus a review fee of $116.50 for each tree, and construction removals that cannot be replaced on the lot are charged $450 for each 6 cm replacement tree not planted.
Conservation authority. Newmarket lies in the Lake Simcoe Region Conservation Authority’s watershed, and lots near the East Holland River and its tributaries can sit inside a regulated area that needs an LSRCA permit. The Town’s Navigate Newmarket map shows whether a property is affected.
Heritage. Newmarket has one heritage conservation district, Lower Main Street South, with 72 properties, and 93 more properties are designated individually. Alterations to or demolition of any of them need a heritage permit, while routine maintenance with matching materials does not.
◆ A Newmarket file, start to finish
How a Newmarket Application Moves
Applications are filed and tracked through the Town’s Development Portal. Drawings go in as unlocked, black-and-white PDFs; zip files, JPEGs and links to file-sharing sites are not accepted.
01
Assess
Address, zoning and history
Confirm the zone and suffix, check the heritage and LSRCA layers for the lot, and find any permits already issued for the house.
Intake
02
Check
Zoning Preliminary Review
Send the site plan and basic drawings for the review, and settle any variance before detailed design starts.
Feasibility
03
Prepare
Drawings and side permits
Finish the permit set, and apply for tree or LSRCA permits at the same time where the property needs them.
Drawings
04
File
Portal upload and deficiency letter
Pay the permit fee with the upload. A complete file is reviewed in about 10 to 15 working days, and any gaps come back in a deficiency letter.
Municipal
◆ Newmarket projects
Common House Projects in Newmarket
The kinds of work most Newmarket permit questions are about.
SECOND UNITS
Newmarket Basement Units
Second units inside the house, planned around parking, exits and fire separation, then registered with the Town.
ADDITIONS
Rear and Second-Storey Additions
Additions checked through the Zoning Preliminary Review before structural drawings are prepared.
DECKS
Decks and Below-Grade Entrances
Raised decks, porches and new basement walk-downs, each reviewed for zoning before the permit application.
GARAGES
Garages and Garden Suites
Detached garages, sheds over 15 m² and detached units under the 2026 zoning rules.
ZONING
Minor Variance Applications
Committee of Adjustment applications when the review shows a design does not meet the zoning by-law.
Newmarket Permit Fees for 2026
Newmarket raised most of its permit rates by 2% for 2026 and left the flat fees unchanged. The amounts below come from the Town’s 2026 fee schedule.
Item | 2026 fee |
Additional unit inside an existing house | $1,000 flat |
Deck, per dwelling unit | $300 flat |
Below-grade entrance | $500 flat |
Demolition, building up to 600 m² | $500 flat |
Permit revision | $200 per hour, $200 minimum |
Non-refundable payment at application | $200 up to $50,000 of construction value, $500 up to $500,000, $1,000 above |
Additional unit registration (Legislative Services) | $268.93, one time |
New houses, additions and renovations are charged under the residential rates in the same schedule. Development charges, including education charges, are calculated once the zoning, grading and Building Code reviews are done, before the permit is issued.
Planning Work on a Newmarket Property?
Send the address and a short description of the project to find out which Newmarket approvals it needs and in what order.
◆ Why iPermit?
Before You Hire Help in Newmarket
Newmarket files are usually delayed by things outside the drawings: a review that was skipped, a parking layout that does not fit the driveway, or a registration package that arrives without a current ESA report. When comparing consultants, ask who handles the Zoning Preliminary Review, who coordinates tree and LSRCA permits, and who answers the deficiency letter. The Town reviews the application, issues the permit and inspects the work; a consultant prepares and coordinates the file within the agreed scope.
◆ Newmarket owners often ask
Newmarket Permit Questions
Short answers to questions that come up on Newmarket projects.
How tall can a garden suite be in Newmarket?
A one-storey detached unit can reach the lower of the house height or 5.5 m with a pitched roof, or 3.5 m with a flat roof. A two-storey unit can reach the lower of the house height or 6.5 m, or 5.5 m with a flat roof. Rooftop patios are not allowed.
Does my deck need a permit in Newmarket?
It does if it is larger than 10 m², attached to the house, or 600 mm or more above grade. Sheds need one once they are larger than 15 m².
My basement apartment was built before 1995. Can it be registered?
Yes. Older units are registered with a letter from Central York Fire Services confirming Fire Code compliance, an ESA report for both units dated within the last six months, a parking sketch and the application form.
What do the N plate and B address mean?
They mark a house with a registered additional unit. The plate and the B suffix on the address tell emergency crews there are two homes inside, and a registered house can put out six garbage bags instead of three.
How soon do I have to start after the permit is issued?
Work has to start in earnest within six months, or the Town can revoke the permit. Inspections are booked with two days’ notice.