Top 5 Insulation Contractors
in Guelph
We compared 5 Insulation Contractors serving Guelph, Ontario using publicly available business information, including customer reputation, local presence and documented services. Across the businesses featured here, documented specialties include Spray foam insulation, Blown-in insulation, and Cellulose insulation.
≈ Guelph’s featured insulation contractors have a FiveBest Score in line with the Ontario benchmark.
Reitzel Insulation serves Guelph with residential and commercial insulation for new construction, renovations and existing buildings. Its documented options include spray foam, blown-in and cellulose insulation, plus drill-and-fill work for wall cavities. The company assesses building conditions and performance goals to select an appropriate approach.
Spray foam insulation · Blown-in insulation · Cellulose insulation
Great Northern Insulation documents attic insulation, insulation removal and spray-foam applications for Guelph projects. Its Milton location serves the area, and the company describes a hybrid attic retrofit approach that combines spray foam with blown cellulose or fibreglass insulation.
Attic insulation · Spray foam insulation · Blown-in cellulose and fibreglass insulation
Detailed FiveBest Research is not yet available for this business.
Detailed FiveBest Research is not yet available for this business.
Detailed FiveBest Research is not yet available for this business.
Guelph insulation contractors are in line with the Ontario benchmark
Featured insulation contractors in Guelph have a median FiveBest Score™ of 77/100, compared with 77/100 for featured insulation contractors across Ontario.
Among nearby FiveBest markets, insulation contractors in Kitchener (83/100) and insulation contractors in Cambridge (81/100) score higher, while Waterloo (71/100) scores below Guelph.
Comparison based on profiles currently featured by FiveBest in this category with an available FiveBest Score™.
How we researched Insulation Contractors in Guelph
FiveBest reviews publicly available information for Insulation Contractors serving Guelph.
- Google rating and review history
- Documented services
- Years in business when available
- Guelph and surrounding service coverage
- Business website and online presence
- Independent reputation signals when available
Research last updated: September 2026
Common Services
- Attic insulation in Guelph
- Blown-in insulation in Guelph
- Spray foam insulation in Guelph
- Wall insulation in Guelph
- Basement insulation in Guelph
- Air sealing in Guelph
FiveBest Match™
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FiveBest Match™ — Coming Soon 🔒How to Choose an insulation contractor in Guelph
Compare insulation contractors in Guelph for attic insulation, blown-in cellulose or fibreglass, spray foam, wall and basement insulation, air sealing, insulation removal, vapour-barrier work and energy-efficiency upgrades. FiveBest helps homeowners compare selected local insulation companies based on relevant services, online reputation and local presence.
Compare selected insulation contractors in Guelph for attic insulation, blown-in insulation, spray foam, wall insulation, air sealing, insulation removal and energy-efficiency upgrades.
Ask how current insulation, air leakage, moisture and ventilation conditions will be assessed before adding material.
Confirm insulation type, target thermal value, installed depth or thickness and areas included.
Ask whether air sealing or moisture problems should be corrected before insulation is installed.
Check removal, air sealing, insulation, ventilation baffles, access work, cleanup and disposal.
For spray foam or other specialized products, confirm trained installation, ventilation and occupant instructions.
Ask what documentation is provided for applicable energy programs and what product or workmanship warranties apply.
What Affects Insulation Costs
- Area being insulated
- Existing insulation
- Insulation material
- Target R-value
- Removal of old material
- Air sealing requirements
- Accessibility
- Ventilation modifications
- Moisture remediation
- Cleanup and disposal
Questions to Ask an Insulation Contractor
- How will you assess the existing insulation and air leakage?
- What insulation material and target R-value are specified?
- Is old insulation removal required?
- Is air sealing included?
- How will attic or roof ventilation be maintained?
- Are there moisture issues to correct first?
- What documentation is provided for applicable rebates?
- What product and workmanship warranties apply?
Frequently Asked Questions
Insulation costs in Guelph depend on the area to cover, insulation material, existing insulation, required R-value, accessibility, air-sealing work and whether old insulation must be removed. A site inspection helps determine the appropriate scope and price.
The best option depends on the attic condition, existing insulation, ventilation, moisture control, target R-value and budget. Blown-in cellulose or fibreglass are common options, while spray foam may be appropriate in specific assemblies.
Improving attic insulation and air sealing can reduce heat loss and improve comfort when the existing insulation is inadequate. Actual savings depend on the home, climate, heating system and the quality of the installation.
Not always. Existing insulation may sometimes remain if it is dry, clean and in good condition. Removal may be recommended when insulation is contaminated, wet, damaged, compressed or interfering with repairs or air sealing.
Compare experience with the insulation system you need, inspection process, proposed R-value, air-sealing scope, ventilation considerations, product specifications, warranties, cleanup, applicable certifications and recent local reviews.
Programs and eligibility can change over time. Ask the contractor whether current provincial, utility or federal efficiency programs may apply and confirm eligibility with the program provider before starting work.