Straight answers
Spray Foam Insulation FAQ for Guelph Homeowners and Businesses
These are the questions we hear most often on estimates and phone calls across Guelph, Waterloo Region and Wellington County. Each answer is short, with a link to the page that covers the topic in depth. If your question isn't here, call us at 226-780-8752, seven days a week.
- In business since 2018
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Cost and Quotes
How much does it cost to spray foam 1,000 square feet?
At 2 inches of closed cell foam, 1,000 square feet typically costs about $3,300 to $5,300 installed in 2026. Open cell at full cavity depth in a wall costs less per square foot. The cost guide walks through the math.
Is spray foam cheaper than regular insulation in the long run?
Spray foam costs more up front, but it air seals as well as insulates, which batts don't. Whether it pays back faster depends on how leaky the space was. Our spray foam vs other insulation guide compares them honestly.
What time of year is insulation cheapest?
Prices don't swing much by season, but scheduling does. Late spring and summer are usually easier to book, while fall fills up fast as people prepare for winter.
Safety and Curing
Why are people removing spray foam insulation?
Almost always because of a bad install, such as an off-ratio mix or foam sprayed too thick, which can leave a lingering odour or poor adhesion. Properly installed foam rarely needs removal. Our spray foam safety guide explains the causes.
How long does spray foam take to cure?
Closed cell foam is firm within minutes and substantially cured within a day. Re-occupancy follows the manufacturer's instructions, commonly 24 hours for closed cell.
Can mould grow behind spray foam?
Not when closed cell foam is bonded to a dry surface, because there is no gap for moist air to condense in. Problems arise when foam covers a liquid leak or wet material. See our mould removal page.
Choosing the Right Insulation
What is the difference between open cell and closed cell?
Closed cell is dense, gives about R-6 per inch and controls vapour. Open cell is soft, gives about R-3.6 per inch and needs a separate vapour barrier. Our comparison guide explains where each belongs.
Can you spray foam a finished basement?
Only where the walls are open, so most finished basements need the drywall removed first. Rim joists can often be reached from the furnace room. See our basement spray foam page.
Will spray foam stop mice getting in?
It seals many of the gaps mice use, but it isn't chew-proof on its own. Our pests guide covers what else to do.
Code, Rebates and Paperwork
Is spray foam code compliant in Ontario?
Yes, when the product is evaluated for use in Canada, installed to CAN/ULC-S705.2 and covered by a thermal barrier where required. Our Ontario Building Code guide has the details.
Can I get a rebate for insulation in Ontario?
Yes. The Home Renovation Savings Program offers a standalone attic rebate and larger multi-measure rebates. Our rebates guide explains who qualifies.
Will spray foam affect my mortgage or home sale?
Concerns about lenders refusing spray foam homes come mostly from the UK and are rarely an issue in Ontario. Keeping your installation records helps if a buyer or lender asks, as explained in our safety guide.
Before and After Your Install
How do I get my home ready for spray foam?
Clear the work area, move stored items away from the walls and arrange for pets and family to be out of the house. We shut off the HVAC and handle the masking.
Do you remove old insulation first?
Yes, where foam needs to bond to the surface. Wet, mouldy or contaminated insulation is removed as part of our insulation removal service.
How long does a typical job take?
Rim joists usually take a few hours, and a basement is often done in a day. Larger homes, barns and commercial jobs take longer, and your quote will include a timeline.