Spider Treatment in Montreal
Webs taking over your home? Spiders invading your basement and storage areas? Blackline Pest Control eliminates spider populations with targeted perimeter spray and interior treatments — safe for your family and pets.
Why Spider Infestations Spike in Montreal Homes
Montreal's dramatic seasonal transitions — particularly the shift from summer to fall — trigger mass spider migrations indoors. As temperatures drop in August and September, spiders seek warm shelter inside homes, apartments, and commercial buildings. Montreal's older housing stock, with its abundance of cracks, gaps, and unfinished basement spaces, provides ideal harborage for dozens of spider species.
While most spiders found in Montreal homes are harmless — common house spiders, cellar spiders, and wolf spiders — their presence is unsettling and can indicate a larger pest problem. Spiders are predators that follow their food source. A significant spider population almost always means there is an underlying insect infestation providing them with prey. Treating spiders without addressing the insect population is only a temporary solution.
The yellow sac spider (Cheiracanthium inclusum) is the most common biting spider in Quebec and can cause painful, slow-healing wounds. While not life-threatening for most people, bites can cause significant discomfort and secondary infection. The northern black widow has also been documented in Quebec, though it is rare.
Blackline Pest Control's spider treatment program addresses both the spider population and the underlying insect problem. We apply a residual perimeter spray around the entire foundation, treat interior harborage areas, remove existing webs and egg sacs, and provide recommendations for reducing conditions that attract spiders.
How We Treat Spiders in Montreal
A comprehensive approach that eliminates spiders and addresses the insect population that sustains them.
Inspection & Species ID
We inspect the property to identify spider species, locate harborage areas, assess web density, and identify the insect population sustaining the spider colony. This determines whether exterior-only or combined interior/exterior treatment is needed.
Exterior Perimeter Spray
We apply a residual insecticide barrier around the entire foundation, window frames, door thresholds, eaves, and utility penetrations. This kills spiders on contact and creates a long-lasting barrier that prevents new spiders from entering.
Interior Treatment & Web Removal
For interior infestations, we treat cracks, crevices, basement corners, and storage areas with targeted insecticide. We physically remove all visible webs and egg sacs to eliminate the next generation before it hatches.
Insect Control & Prevention
We address the underlying insect population that attracts spiders. We also provide recommendations for reducing exterior lighting, sealing entry points, and reducing clutter in storage areas. Our 100-day guarantee covers free re-treatment if spiders return.
Pricing & Our 100-Day Guarantee
Exterior Perimeter Only
- Full perimeter spray
- Web removal (exterior)
- 100-day guarantee
- Follow-up visit
Interior + Exterior
- Full perimeter spray
- Interior crack & crevice treatment
- Web & egg sac removal
- Insect control included
- 100-day guarantee
Seasonal Program
- Spring & fall treatments
- Year-round protection
- Priority scheduling
- 100-day guarantee
- Discounted rate
Signs of a Spider Problem in Your Montreal Home or Business
Webs in Corners, Ceilings, and Basements
Finding multiple webs in corners, along ceiling edges, in basement areas, and around window frames indicates an established spider population. Different species build different web types — funnel webs, cobwebs, and orb webs each point to different species.
Egg Sacs Attached to Webs or Surfaces
Spider egg sacs are small, silky pouches attached to webs, walls, or hidden surfaces. A single egg sac can contain 100–400 eggs. Finding egg sacs means a population explosion is imminent if not treated promptly.
Spiders Appearing Frequently Indoors
Seeing multiple spiders per week inside your home — especially in bathrooms, basements, and storage areas — indicates a significant population. Spiders are solitary, so frequent sightings suggest many more are hidden in crevices and wall voids.
High Insect Activity (Spider Food Source)
Spiders follow their food. If you have a significant insect problem — flies, mosquitoes, moths, or other small insects — spiders will congregate where prey is abundant. Treating the underlying insect problem is part of our spider control approach.
Webs Around Exterior Lights and Vents
Exterior lights attract insects at night, which in turn attract spiders. Finding dense webs around porch lights, garage lights, and ventilation openings indicates spiders are actively hunting in these areas and may be entering your home.
Spiders in Garage, Shed, or Storage Areas
Garages, sheds, and storage areas with clutter provide ideal harborage for spiders. These areas are often the source of indoor spider problems, as spiders migrate from storage spaces into living areas through gaps and cracks.
Signes d'araignées / Señales de arañas
🇫🇷 Toiles dans les coins · Sacs d'œufs · Araignées fréquentes · Insectes abondants · Toiles autour des lumières · Araignées dans le garage
🇪🇸 Telarañas en rincones · Sacos de huevos · Arañas frecuentes · Insectos abundantes · Telarañas alrededor de luces · Arañas en el garaje
We Treat Spiders Across Montreal and Surrounding Areas
Condos & commercial
Heritage triplexes
Older wooden homes
Large heritage properties
Suburban homes & garages
South Shore residences
New developments
Commercial & industrial
Riverfront properties
Family homes & basements
East-end residential
Residential & commercial
Frequently Asked Questions About Spider Treatment in Montreal
Are there dangerous spiders in Montreal?
Most spiders in Montreal are harmless, but the northern black widow (Latrodectus variolus) has been found in Quebec and its bite can cause serious symptoms. The yellow sac spider is also present and can cause painful bites. If you are unsure of the species, professional identification is recommended.
Why do I suddenly have so many spiders in my Montreal home?
Spider populations spike in late summer and fall as they seek warm shelter before winter. A sudden increase in spiders often indicates an underlying insect problem — spiders follow their food source. Treating the insect population reduces the spider population naturally.
How long does spider treatment last?
A professional perimeter spray treatment typically remains effective for 60–90 days. We recommend seasonal treatments — spring and fall — for properties with recurring spider problems. Our 100-day guarantee covers free re-treatment if spiders return within the guarantee period.
Is spider treatment safe for children and pets?
Yes. We use Health Canada-approved products with low mammalian toxicity. Exterior perimeter sprays are applied to the foundation and entry points. Interior treatments use targeted applications in cracks and crevices. Children and pets can return to treated areas once the product has dried, typically within 1–2 hours.
Do I need to leave my home during spider treatment?
For exterior-only treatments, you do not need to vacate. For interior treatments, we recommend that residents, children, and pets leave during the application and return 2 hours after treatment is complete and the area has been ventilated.
How much does spider treatment cost in Montreal?
Spider treatment in Montreal starts at $199 for a single-unit exterior perimeter treatment. Interior treatments and larger properties may cost $250–$500. We provide a free inspection and transparent quote before any work begins.
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Learn MoreWhat Clients Say About Our Spider Treatment Service
Real feedback from Montreal homeowners and businesses we've helped.
“Every fall our basement fills with spiders — it was getting out of hand. Blackline came the same day, did a full perimeter spray and treated the basement interior. It's been two mo...”
“We have a large heritage home with a lot of exterior crevices and the spider situation every fall was embarrassing. Blackline treated the entire perimeter and removed all the webs ...”
“Found what I thought might be a black widow in my garage — called Blackline in a panic. They were there within 3 hours, identified the spider (it was a harmless cellar spider, than...”
“Our backyard deck had become completely covered in webs — we couldn't use it. Blackline did an exterior treatment and web removal, and also treated the garage. Within a week the de...”
“Good service overall. The technician was knowledgeable and the treatment worked well. Spiders are mostly gone from the main living areas. The basement still has a few but they came...”
“I manage a small apartment building and the common areas were full of webs every fall. Blackline did a building-wide exterior treatment and interior treatment of the common areas. ...”
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