Common questions from Markham homeowners about windows and glass

Often the window can stay. A glass pro measures the fogged unit and orders a replacement built to its exact size and shape, which matters most for half-rounds and tall foyer units. If the frame itself is failing, or fog has spread to several units, also price replacement windows.

They overlap:

• Foggy window, broken seal: moisture has got between the panes.
• Sealed unit: panes, spacer and seal made as one piece.
• Thermopane: an older name for it, still used in Unionville's heritage plan.
• Grilles between the glass: a grid built into the unit, between the panes.
• Simulated divided lites: bars on the glass faces that mimic separate panes.

It can clear the haze, but it doesn't restore the failed seal, so it suits a unit you'll live with for a while, not one you want fixed for good. A new sealed unit is the lasting repair, fitted to the existing frame; foggy sealed units compares both.

Start with what a buyer's inspector will notice: fogged units, cracked panes, a crank that won't turn. Those are usually glass or hardware jobs, not new windows; keep the invoices for the listing file. For the whole-house question, see our guide on repairing or replacing

Complete ENERGY STAR windows and doors can earn a per-opening rebate from Ontario's Home Renovation Savings program, usually alongside a home energy assessment. A sealed unit on its own doesn't count, and conditions change, so check the program page. For repair, the local option is the City's heritage grant, below.

Yes. The Greener Homes loan and grant have both closed, even though the City's energy page still lists the loan; Natural Resources Canada confirms the grant has ended. For windows today, look at the provincial Home Renovation Savings program instead.

No. Markham Windows is a free referral service. The glass and door businesses we connect you with are independent, and none of them work for us. We pass your request on and follow it up if it stalls; measuring, quoting and the work belong to the pro. How it works explains more.

Not a building permit, if the rough opening stays the same size, says the City of Markham. Enlarging an opening, changing a structural wall or adding a basement entrance needs one. In the four heritage districts, any window change needs a heritage permit first, whatever the size.

Usually. Windows and balcony doors are normally common elements, so a change needs a board resolution and a section 98 agreement registered on title. Ask the management office before booking anyone, and keep the approval in writing; the Markham Centre page explains more.

You need a heritage permit before changing windows, replacements included. Each district plan favours repairing original sash and frames over replacing them, wants any replacement to match in material and proportion, and doesn't accept snap-in or tape-on grilles; Markham Village adds that original glass should be reused. The heritage district guide goes further.

Yes. Window and door repair on eligible heritage properties is among the work Markham's Heritage Property Grant, introduced in 2026, can help fund, and applicants supply two professional quotes covering identical work. Eligibility and intake are in the City's grant guidelines; if you intend to apply, say so in your quote request.