Quick answer: Pro Home Insulation tops up and replaces attic insulation across Markham, from heritage homes in Markham Village to newer builds in Cornell. If your attic is R-12 or less and you upgrade to at least R-50, you may get up to $1,250 back through Ontario’s Home Renovation Savings Program, with no energy assessment needed. The program is currently scheduled to run until March 31, 2027, and amounts can change.
Updated November 2026
On this page
- What attic problems do Markham homes have?
- How can you check your Markham attic yourself?
- How much can a Markham homeowner get back?
- Key numbers for Markham homeowners
- Which insulation suits a Markham attic?
- How does our Markham attic process work?
- Markham attic checklist
- Example project (illustrative)
- Neighbourhoods we serve in Markham
- 6 questions to ask any attic insulation contractor
- Frequently asked questions
- Get a free attic assessment
What attic problems do Markham homes have?
Markham’s housing spans more than a century, so attics vary a lot from street to street.
- Thin insulation in 1970s and 1980s homes. Many split-levels and two-storeys in Milliken, Thornhill and Markham Village were built with far less than today’s R-60 code target for new homes.
- Uneven coverage after renovations. Pot lights, bathroom fans and wiring runs often leave gaps or crushed areas that were never refilled.
- Heritage roof lines. Older homes on Main Street Unionville and in Markham Village can have low, tight attics that need careful access and air sealing.
- Blocked soffit vents. Loose insulation pushed into the eaves stops airflow and can lead to frost and ice dams in winter.
- Rooms over garages. Common in Cachet, Berczy Village and Greensborough, these rooms often feel cold because the floor and side walls are poorly sealed.
- Wildlife damage. Raccoons and squirrels in mature, treed neighbourhoods can flatten insulation and leave droppings behind.
How can you check your Markham attic yourself?
Start at the attic hatch, usually in a bedroom closet or hallway ceiling. Use a flashlight and a ruler, and stay on the joists.
Measure the insulation depth in a few spots. As a rough guide, blown fiberglass gives about R-2.5–3 per inch, so 4 inches is only around R-10–12. If you can see the tops of the ceiling joists, you are almost certainly under R-25. Our guide on how to check attic insulation R-value walks through it step by step.
If you see grey-brown, pebble-like granules, stop and do not disturb them. That may be vermiculite.
How much can a Markham homeowner get back?
The standalone attic rebate pays 50% of your after-tax insulation cost, up to the tier maximum. See the full rules on our Ontario attic insulation rebate page.
| Attic before upgrade | Upgrade to at least | Maximum rebate |
|---|---|---|
| R-12 or less | R-50 | up to $1,250 |
| Above R-12 to R-25 | R-50 | up to $1,000 |
| Above R-25 to R-35 | R-50 | up to $800 |
| Cathedral/flat roof, R-25 or less | R-28 | up to $750 |
| Cathedral/flat roof, R-12 or less | R-20 | up to $650 |
Amounts can change, and funding is first-come, first-served. Check current details on our rebates hub.
Key numbers for Markham homeowners
- Ontario’s building code targets about R-60 for attic ceilings in most new homes (Ontario Building Code, SB-12).
- Air leakage represents about 20–30% of heat lost from an older home (Natural Resources Canada).
- One small air leak can let in 100 times more moisture than diffusion through the same area (Natural Resources Canada).
- Going from R-12 to R-50 cuts heat flow through the insulation layer by about 76%, simplified (1 − 12/50).
Which insulation suits a Markham attic?
Any material qualifies for the rebate as long as you reach the target R-value.
| Material | About R per inch | Best for | Watch for |
|---|---|---|---|
| Blown fiberglass | R-2.5–3 | Open attics, quick top-ups | Needs more depth to reach R-50 |
| Blown cellulose | R-3.5 | Open attics, filling around obstacles | Must keep soffit vents clear |
| Closed-cell spray foam | R-6–7 | Rooms over garages, tight spots | Higher cost per area |
Compare them in detail in cellulose vs fiberglass vs spray foam.
How does our Markham attic process work?
- Free assessment. We measure your current R-value, check ventilation and look for moisture, pests or vermiculite.
- Written quote. You get a clear scope, target R-value and the rebate tier you are likely to fall under.
- Prep and air sealing. We seal top plates, wiring holes and light fixtures before adding insulation.
- Install. We install baffles at the eaves and blow insulation to at least R-50.
- Paperwork. You receive the invoice and details needed for your rebate submission.
Markham attic checklist
- Find and clear access to the attic hatch
- Note any cold rooms, especially over the garage
- Look for staining on ceilings near exterior walls
- Confirm you own the home and heat with Enbridge Gas or another eligible fuel
- Ask whether your contractor is a participating contractor before you sign
Example project (illustrative)
example — not a specific customer.
A 1978 two-storey home in Milliken has about R-12 of old fiberglass, with gaps around pot lights. The plan is air sealing plus blown insulation to R-50.
- After-tax insulation cost: $3,000
- 50% of cost: $1,500
- Tier maximum (R-12 or less to R-50): $1,250
- Estimated rebate: $1,250 (the lower of the two)
- Net insulation cost: $3,000 − $1,250 = $1,750
Neighbourhoods we serve in Markham
- Unionville
- Markham Village
- Thornhill (Markham side)
- Milliken
- Cornell
- Cathedraltown
- Berczy Village
- Angus Glen
- Wismer
- Greensborough
- Box Grove
- Cachet
- Buttonville
- Raymerville
We also serve nearby areas, including Richmond Hill, Vaughan and Scarborough.
6 questions to ask any attic insulation contractor
Use these before you sign a quote, with us or anyone else.
- What R-value is my attic now, and how did you measure it?
- What R-value will I end up with, and which rebate tier is that?
- Will you air seal before insulating, and what exactly will you seal?
- How will you keep soffit vents open?
- What happens if you find vermiculite, mould or animal waste?
- Is the rebate paperwork included, and are you a participating contractor?
For side-by-side pricing, try our insulation quote comparison template.
Frequently asked questions
Do I need an energy assessment for the Markham attic rebate?
No. The standalone attic path does not need an energy assessment. You only need to own the home, use an eligible heating fuel and have the work done by a participating contractor.
My townhouse in Cornell is fairly new. Is it worth topping up?
It depends on what is up there now. Some newer homes have settled insulation or thin spots near the eaves. A quick measurement will show whether you fall into a rebate tier and whether a top-up makes sense.
Can you insulate the room over my garage?
Yes. These rooms usually need air sealing and sometimes spray foam in the floor or side walls, not just more attic insulation. We look at the whole space during the assessment.
What if my older Markham home has vermiculite?
Do not disturb it. Health Canada advises treating vermiculite as if it contains asbestos until tested. We can arrange vermiculite removal through qualified professionals before new insulation goes in.
How long until the rebate arrives?
Rebate cheques typically arrive within a few months after the submission is approved. Timing can vary, so keep your invoice and project details handy.
Will you remove old, dirty insulation first?
If the old insulation is damaged by pests, moisture or mould, we usually recommend insulation removal before adding new material. If it is clean and dry, a top-up is often fine.
Get a free attic assessment
Pro Home Insulation has more than 10 years of experience insulating attics across York Region and the GTA. We will measure your attic, explain your rebate tier and give you a clear written quote. Call (647) 250-0606 or Book online.