Don Mills was the first planned community of its kind in Canada. Development began in the early 1950s on what had been farmland, and it was laid out on principles that were genuinely radical at the time: curved streets instead of a grid, houses set back on generous lots, mature trees kept wherever possible, and a deliberate mix of housing types rather than block after block of the same thing.

The architecture followed. Low horizontal rooflines, big windows, open main floors, brick and wood rather than brick alone. Renovating one of these houses is a slightly different exercise from renovating any other postwar North York home, because the design was intentional and it is easy to spend a lot of money erasing the very thing that makes the house good.

What You Have Got

The typical Don Mills house has a few consistent features worth naming, because they drive every decision that follows.

Ceilings are often lower than modern taste expects, but the rooms are wide and the windows are large, so the houses feel bigger than the numbers suggest. Main floors were frequently designed as connected spaces before open plan was a phrase, which means the renovation work other postwar houses need most has often already been done by the original architect.

Roofs are shallow. That matters more than it sounds: a low slope limits what you can do in the attic and rules out some of the additions that work on a steeper roofed bungalow.

And the lots are good. Wide, well treed, and laid out with the street rather than in rigid rows.

The Mistake People Make

The most common error we see is renovating a Don Mills house as though it were a generic bungalow: replacing the long horizontal windows with smaller punched openings, swapping wood cladding for stone veneer, adding a steep roofed second storey that fights the original line, and putting in a kitchen that would suit a new build in Vaughan.

The result is a house that has lost its character and gained nothing but square footage. In a neighbourhood where the architecture is a large part of why people want to live there, that is value going backwards.

You do not have to turn the place into a museum. You do have to notice what you are removing before you remove it.

Renovations That Work With the House

Kitchens

Mid-century main floors take a modern kitchen very well, because the space is already open and the sightlines already work. Flat slab doors, full height cabinetry to handle the lower ceiling, and a long uninterrupted counter suit these rooms far better than heavily detailed traditional cabinetry, which looks fussy under a low ceiling.

The one thing worth spending on is the connection to the garden. These houses were designed to look out. A larger opening or a proper glazed door at the back does more for daily life than another run of cupboards. Our kitchen team can show you the layout in 3D before anything is ordered, which is particularly useful when ceiling height is tight.

Windows

Original windows in these houses are usually single glazed and well past their life. Replacing them is one of the best things you can do for comfort, and one of the easiest ways to wreck the exterior.

Keep the proportions. If the original was a wide horizontal unit, replace it with a wide horizontal unit. Modern frames are thicker than 1955 frames, so insist on seeing the sightline dimensions before you order, because a chunky frame in a long opening changes the whole face of the house.

Bathrooms

Original bathrooms are small and there are rarely enough of them. This is the area where you should feel free to be ruthless, since nobody is preserving a 1956 four piece for posterity. Adding a second or third bathroom is usually possible within the existing footprint by borrowing from an oversized hallway or a bedroom closet.

Additions

Going back rather than up is almost always the right answer here. A rear addition can carry the same low roofline, keeps the street elevation intact, and takes advantage of the deep lot. A second storey on a shallow roofed mid-century house is difficult to do well and easy to do badly.

The Practical Problems

Under the good design sits a 1950s or early 1960s house, with the usual list. Electrical panels are undersized for modern loads and some of these houses are late enough to have aluminum branch wiring. Insulation in the walls is minimal and difficult to improve without opening them. Original galvanized supply plumbing, where it survives, will be restricting your water pressure.

Flat and low slope roof sections need a different approach from a pitched roof and a different set of materials. If your house has one, have it looked at by someone who works on them regularly rather than a general roofer.

The Bottom Line

Don Mills houses reward restraint. The architecture already gives you what most postwar renovations are trying to buy: light, openness and a connection to the garden. Spend your money on the systems that have aged out, on kitchens and bathrooms, and on windows that respect the original proportions.

Resist the urge to make it look like a new house. The people who will eventually buy it are buying the neighbourhood, and the neighbourhood is the architecture.

Ready to Talk?

We work across North York from our Wilson Ave office and we are comfortable working on houses where the details matter. If you have a mid-century house and you want a plan that improves it without flattening its character, book a visit.