Drainage and water management

Grading around the house, eavestroughs and downspout discharge, weeping tile, sump arrangement, and the backwater valve. Together these decide where rain and meltwater go.

Can you do your own drainage and water management work in Ontario?

Mostly yes for the cheap, effective measures: extending downspouts, correcting grade, clearing eavestroughs. Interior or exterior waterproofing systems and backwater valve installation are contractor work and may need a permit.

Authority: Your municipal building department · Source: 2024 Ontario Building Code (O. Reg. 332/12 (2024 edition)) · Reviewed 2026-09-10

Can you work on it yourself?

The expensive interior waterproofing sale is frequently made to homeowners whose actual problem is a downspout discharging against the foundation. Exhaust the cheap exterior measures before buying the expensive interior one.

Authority Your municipal building department

How long it lasts

Grading degrades over years as soil settles. Weeping tile can clog or collapse. Sump pumps commonly 7–10 years, and they fail when they are needed most.

What failure looks like

Water or staining on basement walls or floor after heavy rain
Efflorescence — white mineral deposits — on foundation walls
Soil sloping toward the house rather than away
Downspouts discharging within a foot of the foundation
A sump pump that runs constantly, or one that has never run at all

Worth knowing about your own house

Does the ground slope away from the house on all sides?
Where do the downspouts actually discharge?
Is there a backwater valve, and does the municipality offer a subsidy for installing one?

Project briefs that involve this system

Sources and review

2024 Ontario Building Code O. Reg. 332/12 (2024 edition) in force 2025-01-01 primary source

Reviewed Reviewed 2026-09-10 Next review 2027-09-10 Tier C · 365-day SLA Reviewer: Justin Challenger