Basement Renovations in Newmarket
From the historic downtown and Main Street to Glenway, Armitage and Stonehaven, we finish Newmarket basements and build registered additional residential units.
Registered, Plated and Parked
In Newmarket, a basement unit is not finished when the drywall is done. Every additional residential unit must be registered with the Town, and in 2026 the application fee is $282.82. A registered unit receives an 'N' plate and a 'B' added to its address. Units built after 1995 need an ESA report and a final building inspection report to register; older units need a letter from Central York Fire Services.
Parking is the other hurdle. Each unit needs its own space on top of the two required for the main house, every required space has to be outside rather than in the garage, and each must measure at least 2.6 m by 5 m. The Town's guide also says the front faade of the house must not be altered, so we plan new entrances for the side or rear and check the driveway at the first visit.
Up to three units are allowed on a property, but not on lots in the Floodplain and Other Natural Hazards zone mapped by the Lake Simcoe Region Conservation Authority, so homes near the East Holland River need a zoning check first. About 30% of Newmarket homes were built before 1981, according to the 2021 census, and basements of that age may need to be opened up to meet the current Code.
- Licensed & insured contractors
- Transparent, itemized pricing
- Permits & approvals handled for you
- On-time delivery, every project
Newmarket Basement Costs
Basement finishing in Newmarket starts at $55 per square foot with us, and a registered additional unit at $80 per square foot. A family basement usually costs $50,000 to $90,000. A legal unit typically lands between $80,000 and $175,000, since it needs its own kitchen, separation from the main house, linked smoke alarms, a code-compliant exit and full permit drawings.
Newmarket's fees are predictable: a flat $1,000 permit fee for a unit in existing space, $500 for a below-grade entrance and $282.82 to register. What moves a quote more is whether the parking works as it is, and whether an older basement has to be stripped first. Your quote is fixed and itemized after a site visit, and every Town fee appears as its own line.
Newmarket's Basement Checklist
Six things we confirm for every Newmarket basement unit.
Registration and Fees
$282.82 to register in 2026. A fire retrofit inspection for an older unit is $255.58 with HST.
Outdoor Parking
One space per unit plus two for the house, outside the garage, each at least 2.6 m by 5 m.
Front Faade
The Town guide says the front of the building must not be altered.
Floodplain Exclusion
No additional units on lots in the LSRCA Floodplain and Other Natural Hazards zone.
Permit Fees
A flat $1,000 per unit for an ARU in existing space, and $500 for each below-grade entrance.
Lower Main Street South
In the heritage district, new door and window openings are reviewed, which matters for a new basement entrance.
Newmarket Basement Work
The basement projects Newmarket homeowners ask us for most.
- Registered Basement Units. Units designed to pass the final building inspection and ESA review the Town asks for at registration.
- Registering an Existing Unit. Upgrades and paperwork for older units, including the fire retrofit inspection route.
- Side and Rear Entrances. Below-grade entrances placed so the front of the house stays as it is.
- Family Basements. Rec rooms, offices and guest rooms under a basement finishing permit.
- Basement Bathrooms. New bathrooms with an ejector where needed and a softener connection planned in.
- Older Basement Updates. Opening up pre-1981 finishes and rebuilding with current insulation, wiring and fire protection.
Newmarket Basement Renovation FAQs
What will a registered basement unit cost in Newmarket?
Do basement units have to be registered in Newmarket?
How much parking does a Newmarket basement unit need?
What building permits does a Newmarket basement need?
Can I add a unit to a home near the East Holland River?
Newmarket Basement Facts
Town fees and census figures that shape a basement unit here.
| Units allowed | Up to 3 per property |
| ARU registration (2026) | $282.82 |
| Fire retrofit inspection (2026) | $255.58 including HST |
| Parking | 1 outdoor space per unit + 2 for the main house |
| ARU permit in existing space (2026) | $1,000 flat per unit |
| Homes built before 1981 | About 30% (2021 census) |
Newmarket Neighbourhoods We Serve
We build basements and basement units across Newmarket.