Home Additions in Richmond Hill

The City of Richmond Hill Building Division handles the zoning check, the permit and the inspections; York Region looks after regional roads and servicing. Richmond Hill’s Site Alteration By-law 47-25 applies to pools and residential regrading, with a grading plan by an engineer or surveyor. An addition that changes the grades around the house can fall under it, and our P.Eng prepares the grading plan that application asks for.

If the lot is in a TRCA Regulated Area, yes: building anything there needs a TRCA permit, and Richmond Hill will not issue the building permit until you have it. TRCA also asks for a pre-submission consultation, which we book as soon as the survey shows a valley or creek near the house.

Yes, if it fits the zoning, and that is the first thing we check. Richmond Hill Council passed Comprehensive Zoning By-law 93-25 on September 24, 2025, and the Ontario Land Tribunal partly approved it on July 2, 2026. It is still under appeal for specific areas of the City, and properties it does not cover are still regulated by other applicable zoning by-laws. We confirm which by-law governs your lot and measure the addition against it. If it misses a setback or coverage limit by a little, a minor variance from the Committee of Adjustment can allow it, and the permit follows that decision.

It depends on whether your house is inside it. The City of Richmond Hill names the Gormley Heritage Conservation District as its first Heritage Conservation District under the Ontario Heritage Act. It came into effect on December 13, 2009 and covers the village core of Gormley. For a house inside the district, we ask Richmond Hill what it requires of an addition and design to that; outside it, the usual zoning and permit rules apply.

Yes. We take on home additions across Richmond Hill, including Oak Ridges and Mill Pond, 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 and a survey, if you have one; what you want to add and where; and photos of the side of the house and the yard where it would go. Send those and we tell you what the City of Richmond Hill Building Division will ask for before we quote.

It can, because new footings cut roots. Under Richmond Hill’s Tree Preservation By-law 19-25, injuring a private tree 15 cm or more in diameter at 1.4 m above the ground needs a permit, just as removing it does. We put the surveyed trees on the site plan before the footprint is set, then keep the foundation clear of them or apply for the tree permit before the City of Richmond Hill Building Division gets the drawings.

Yes, if the lot qualifies. By-law 143-24 allows the house plus up to three additional units on a lot served by municipal water and sewer, and a unit can be built into an addition as well as a basement. It then needs its own entrance, fire separation and exit, and we design those into the addition from the start so the City of Richmond Hill Building Division reviews one complete set.

The zoning by-law that governs your lot answers that, CZBL 93-25 or, where it is under appeal or does not apply, the earlier by-law. Each defines lot coverage in its own words, so we read the one for your address and count the porch with the addition before either is sized. If the two together go over, the options are a smaller porch or a minor variance, and the City of Richmond Hill Building Division holds the permit until that is decided.

As high as the height limit in the by-law for your lot, CZBL 93-25 or the earlier by-law where the new one does not apply. That by-law also defines where height is measured from, so we work it out from the grades on your survey before the new walls and roof pitch are fixed, and the City of Richmond Hill Building Division checks the same measurement at zoning review.