Basement waterproofing in Markham comes with its own set of challenges. Expansive clay soil, newer subdivision grading, high groundwater pockets, and aging storm infrastructure all contribute to basement leaks, foundation cracks, and hydrostatic pressure issues.
The companies listed below are established waterproofing and drainage specialists serving Markham and York Region. This list focuses on contractors that diagnose water problems correctly and install long-term systems—not cosmetic fixes.
How These Companies Were Selected
- Active service coverage in Markham and York Region
- Core focus on basement waterproofing, drainage, or foundation water control
- Experience with both interior and exterior waterproofing systems
- Consistent operational presence and completed projects in the area
- Clear service scope and practical recommendations
Best Waterproofing Companies in Markham – 2026
Company Comparison
| Company | Primary Focus | Core Services | Best For |
|---|---|---|---|
| MT Drains & Plumbing | Drainage & water control | Basement drainage, sump pumps, plumbing-related water intrusion | Drainage-first solutions |
| Aquatech Waterproofing | Full-scope waterproofing | Interior & exterior waterproofing, foundation repair | Severe or multi-source leaks |
| RCC Waterproofing | Drainage & foundations | Interior drainage systems, sump pumps | Older homes |
| DryShield Waterproofing | Interior waterproofing | Interior drainage, crack injection | Finished basements |
| Canadian Waterproofing Company | Exterior waterproofing | Excavation, membranes, weeping tile | Exterior foundation exposure |
Company Highlights
MT Drains & Plumbing
Focused on drainage-first waterproofing, addressing the root cause of basement water problems rather than surface symptoms. Strong expertise in basement drainage systems, sump pump installations, and plumbing-related water entry issues. Well-suited for Markham homes where groundwater pressure and drainage failure are the primary concerns.
Aquatech Waterproofing
Handles complex waterproofing projects that require a combination of interior systems and exterior foundation protection. Often selected for homes with recurring leaks or structural concerns.
RCC Waterproofing
Known for practical interior drainage solutions and foundation-related repairs. A solid option for older Markham neighborhoods with aging weeping tile systems.
DryShield Waterproofing
Specializes in interior waterproofing systems, making them a good fit for finished basements or properties where exterior excavation is not feasible.
Canadian Waterproofing Company
Exterior-focused contractor best suited for cases where full foundation wall exposure and membrane installation are required.
Interior vs Exterior Waterproofing in Markham
| Factor | Interior Waterproofing | Exterior Waterproofing |
|---|---|---|
| Typical Cost | Lower | Higher |
| Property Disruption | Basement-only | Yard excavation |
| Effectiveness | Relieves hydrostatic pressure | Protects foundation walls |
| Installation Season | Year-round | Weather dependent |
| Common Use Case | Recurring basement leaks | Exterior wall water intrusion |
Due to lot constraints and finished landscaping, interior drainage systems are commonly used in Markham, often paired with properly sized sump pumps.
Common Basement Water Issues in Markham
- Water seepage after heavy rain
- Hydrostatic pressure beneath basement slabs
- Foundation wall cracks
- Failed or clogged weeping tile
- Undersized or aging sump pumps
Effective waterproofing systems focus on water management and pressure relief, not short-term sealing.
How to Choose the Right Waterproofing Company
Before hiring:
- Identify exactly where water is entering the basement
- Ask why a specific solution is being recommended
- Confirm warranty coverage and limitations
- Avoid contractors offering crack sealing as a standalone solution for active leaks
A proper waterproofing system should be engineered for the property, not guessed.
Final Notes
The best waterproofing companies in Markham prioritize diagnosis, drainage control, and long-term performance. Choosing an experienced local specialist helps prevent repeat water damage and protects the foundation over time.
This guide reflects current waterproofing practices and contractor availability in Markham as of 2026.
