Basement Insulation in Toronto
Cold basement walls pull heat from your home and create condensation that leads to mould and musty odours. Closed-cell spray foam creates a thermal break and vapour barrier in one application—warming your foundation walls and eliminating moisture problems.
Signs Your Toronto Basement Needs Insulation
Most Toronto homes—especially older properties in The Beaches, Riverdale, and Cabbagetown built before 2005—have uninsulated or poorly insulated foundation walls. Here's how to tell.
Cold Floors Above
If your main floor feels cold even with the heat running, your uninsulated basement is pulling warmth down through the subfloor. A thermal break on foundation walls fixes this.
Condensation on Walls
Water droplets or damp patches on concrete walls mean warm interior air is hitting cold foundation surfaces. This moisture feeds mould and damages framing.
Musty Odour or Mould
That damp basement smell is moisture trapped between concrete and fibreglass batts—the perfect environment for mould. Spray foam eliminates the air gap where condensation forms.
High Heating Bills
Uninsulated foundation walls account for 20–30% of your home's total heat loss. Insulating the basement is one of the highest-ROI energy upgrades you can make.
Sagging Fibreglass Batts
Old fibreglass insulation in basement walls traps moisture against concrete, loses R-value when damp, and sags away from the wall creating air gaps. It needs to be replaced, not patched.
Unusable Space
A cold, damp basement isn't a living space—it's wasted square footage. Insulating foundation walls is the first step to turning your basement into a comfortable room.
Open-Cell vs Closed-Cell for Toronto Basements
For basements, closed-cell is almost always the right choice. Here's why.
| Feature | Open-Cell (½ lb) | Closed-Cell (2 lb) |
|---|---|---|
| R-Value per Inch | R-3.7 | R-6.5 |
| Vapour Barrier | No — vapour permeable | Yes — at 2" thickness |
| Moisture Resistance | Absorbs water | Waterproof |
| Structural Strength | Flexible, no racking strength | Adds wall rigidity |
| Mould Resistance | Can harbour moisture | Does not absorb water |
| Thickness for R-20 | ~5.5 inches | ~3 inches |
| Cost per Sq Ft | $1.50 – $3.50 | $2.50 – $4.50 |
| Best For Basements? | Only if exterior is waterproofed | Recommended for all Toronto basements |
Not sure which is right for your basement? We'll assess moisture conditions during your free site visit.
Where We Apply Basement Spray Foam
Complete basement insulation means more than just the walls. We seal every surface where heat escapes and moisture enters.
Foundation Walls (Full Height)
From sill plate to floor slab. Full-height coverage creates a continuous thermal break and vapour barrier across the entire foundation.
Rim Joists
The wood band where your floor system sits on the foundation. One of the biggest air leakage points in any home—spray foam seals it completely.
Sill Plate
The wood-to-concrete connection where air infiltrates. Spray foam bridges this gap and stops drafts from entering at the foundation top.
Window Wells & Bucks
Around basement window frames where gaps allow cold air and moisture in. We seal the entire perimeter of each basement window.
Utility Penetrations
Every pipe, wire, duct, and conduit that passes through the foundation is a potential air leak. We seal each one during application.
Cold Room / Storage Areas
Uninsulated cold rooms connected to the foundation lose heat and introduce moisture. We can insulate or isolate them from your conditioned space.
How Basement Insulation Works
From quote to completion—most Toronto basement jobs are done in a single day.
Free Site Assessment
We inspect your basement, check for moisture issues, measure wall area, and assess existing insulation. You get a detailed written quote.
Prep & Protection
We mask floors, cover belongings, set up ventilation, and remove any old fibreglass if needed. Your basement is protected throughout.
Spray Application
Closed-cell foam is applied to foundation walls, rim joists, and sill plate to the specified thickness—typically 2–3 inches for code compliance.
Inspection & Cleanup
We verify thickness and coverage, trim any excess foam, clean up completely, and walk you through the finished job. Ready for framing and drywall.
Why Toronto Homeowners Choose GTA Foaming
Local expertise, honest pricing, and work we stand behind.
Serving Toronto
We serve all Toronto neighborhoods from our nearby Woodbridge location. Fast response times across downtown, east end, west end, and midtown.
Fully Licensed & Insured
Full liability insurance, WSIB coverage, and installations that meet or exceed Ontario Building Code requirements.
Upfront Pricing
Detailed written quotes before any work starts. No hidden fees, no surprises. We price per square foot so you know exactly what you're paying.
Real Job Photos
We document every project with before and after photos. Check our Toronto project gallery to see our work.
Same-Day Quotes
Contact us in the morning, get a site visit and written quote the same day. We know Toronto homeowners don't want to wait weeks.
Code-Compliant Installs
R-20 minimum for Toronto basement walls (Climate Zone 6) per Ontario Building Code. We don't cut corners on thickness or coverage.
Toronto Neighbourhoods We Serve
Fast basement insulation service throughout Toronto and surrounding communities.
Your Neighbourhood Not Listed?
We serve all of Toronto and the surrounding GTA. Call for a same-day quote.
Call (647) 613-3626What Toronto Homeowners Say
Real feedback from basement insulation projects across Toronto.
"Our Victorian row house in Cabbagetown had terrible basement moisture issues. GTA Foaming removed all the old sagging insulation and sprayed closed-cell foam on the foundation walls. No more dampness, no more mould smell. The transformation was incredible."
"We're finishing our basement in Leslieville to create a rental unit. The crew explained everything, showed up on time, and finished the spray foam in one day. Professional installation and our contractor said it's the best he's seen. Very happy with the results."
"The main floor of our Junction home was always freezing. After insulating the basement walls and rim joists, the temperature difference upstairs was immediate. Our heating bills dropped and we finally have warm floors. Best investment we've made."
Ontario Building Code for Toronto Basements
What you need to know about basement insulation requirements for homes in Climate Zone 6.
R-20 Minimum Required
Ontario Building Code specifies R-20 minimum for basement walls in Climate Zone 6 (Toronto). With closed-cell at R-6.5/inch, 3 inches meets or exceeds code.
Vapour Barrier Built In
Closed-cell spray foam at 2 inches or more acts as a Class II vapour retarder—no additional poly sheeting required. This simplifies your basement finishing process.
Thermal Barrier Required
Exposed spray foam requires a 15-minute thermal barrier (typically drywall) in finished living spaces. We ensure compliance with all fire safety requirements.
Basement Insulation FAQ — Toronto
Common questions about basement spray foam insulation for Toronto homes.
Ontario Building Code requires minimum R-20 for basement walls in Climate Zone 6 (Toronto). With closed-cell spray foam at R-6 to R-7 per inch, 3 inches provides R-18 to R-21 while also acting as your vapour barrier—no additional poly sheeting needed.
For finished or semi-finished basements, insulate the walls to bring the space into your home's thermal envelope. Ceiling insulation is only recommended if the basement will remain permanently unheated and unconditioned.
Yes. Closed-cell spray foam at 2 inches or more acts as a Class II vapour retarder, preventing warm interior air from contacting cold foundation walls where condensation forms. This eliminates the musty smell and mould risk common in Toronto basements.
Basement spray foam in Toronto typically ranges from $2.50 to $4.50 per square foot depending on foam type, thickness, and access. A typical 1,000 sq ft basement costs $2,500 to $4,500. We provide free quotes with exact pricing.
For Toronto basements, we almost always recommend closed-cell spray foam. It provides R-6.5 per inch, acts as a vapour barrier at 2 inches, resists moisture, and adds structural rigidity. Open-cell is only suitable if the basement is already dry with verified exterior waterproofing.
Active water leaks must be addressed before insulating. Closed-cell spray foam handles normal moisture vapour migration through concrete, but bulk water entry from cracks or failed weeping tile needs to be fixed first. We assess moisture conditions during your free site visit.
Most Toronto basement spray foam jobs are completed in one day. A typical full-basement application (foundation walls and rim joists) takes 4–6 hours including prep, application, and cleanup.
Yes. After spray foam cures (24 hours), you can frame directly over it or against it and install drywall. The foam itself acts as the vapour barrier, so no additional poly sheeting is needed behind the drywall.
Get Your Free Basement Insulation Quote
Serving The Beaches, Leslieville, Riverdale, The Junction, High Park, Rosedale, and all of Toronto. Same-day site visits available.