Legal Basements in Markham

A building permit for the unit, applied for with drawings at Markham’s own building department rather than York Region. The stairwell for a new entrance changes the grade beside the house. Markham’s site alteration by-law is aimed at larger sites, and infill and additions go through the city’s RIGS grading review, so we confirm with the city which of the two, if either, covers a stairwell. We prepare and file the set and deal with the examiner’s comments.

Only where the lot is inside Toronto and Region Conservation Authority (TRCA) regulation, near a watercourse, a valley or a floodplain. Digging a stairwell down to the basement changes the grade there, and the TRCA permit may be needed before Markham issues the building permit. Markham’s unit rule also leaves out hazard lands the TRCA prescribes, so on those lots the mapping decides whether the unit is allowed at all. We read it before anything else.

Under Zoning By-law 2024-19, Markham permits additional residential units only on lots containing a detached, semi-detached or townhouse dwelling. No more than two can be located entirely within the house, and where an additional residential unit is located in an accessory building, only one is permitted in the house. Additional residential units are not permitted in a GWY1 zone or within hazard lands as prescribed by the Toronto Region Conservation Authority. So we check the zone first: in one of the excluded zones the unit is not allowed however well the basement measures up.

Yes. We take on legal basements across Markham, including Unionville and Thornhill, about half an hour from our Richmond Hill office. The first consultation is free, by phone or on site.

Three things to start: property address; basement ceiling height, measured floor to joist; and photos of the basement, the mechanical room and the outside wall where an entrance could go. Send those and we tell you what the City of Markham Building Standards Department will ask for before we quote.

Yes. Markham handles plans review in ePLAN, where the applicant logs in to read the examiner’s mark-ups and comments, and we send you each round with our answers. We revise the fire separation or exit details the examiner asks about and resubmit in the same portal until the Building Standards Department issues the permit.

It can. Digging a stairwell or a larger window well cuts roots, and Tree Preservation By-law 2023-164 requires a permit before a private tree 20 cm or more across, measured 1.37 m up, is injured, healthy or not, with City trees covered as well. We plot the trees from the survey and put the entrance on a side of the house that avoids them where the yard allows, and where it does not, we apply for the tree permit while the Building Standards Department reviews the unit.

That depends on what the district asks, so we find out before the entrance is drawn. Markham’s four heritage conservation districts take in Thornhill and Buttonville as well as the Unionville and Markham Village cores, and a new stairwell changes the outside of the house. We look at a side or rear position first, since either leaves the front as it is, and we settle what the district requires before the set goes into ePLAN.

Yes. We measure what was built, compare it with the Building Code and with Section 4.9.9 of By-law 2024-19, and draw the changes the unit still needs, such as a fire separation or a bigger bedroom window. The drawings go to the Building Standards Department as a new application on ePLAN, and the unit is inspected as that work is done.

Yes. We look the address up on the City’s interactive zoning map to see which by-law covers it, confirm the lot is outside a GWY1 zone and TRCA hazard lands, and walk the basement for headroom and a workable entrance. Our team includes a real estate broker, so we can also talk through what a legal second unit would mean for the property’s value.