Frequently Asked Questions

Published Ontario contractor pages for 2025–26 put exterior waterproofing at about $100 to $350 per linear foot of wall, commonly $150 to $250. Interior drain and sump systems run about $70 to $150 per linear foot. These are published figures, not rates: deeper foundations and tight access cost more, and whether the drain tile is replaced changes the scope, so compare written quotes for the same scope.

The City's Residential Protective Plumbing Program covers protective plumbing devices, not membranes, crack repairs or drain tile. Its table lists: indoor sanitary backwater valve up to $1,000; storm backwater valve up to $1,000; outdoor storm backwater valve up to $2,500; sump pump with battery backup in an existing pit up to $1,500, or up to $3,000 with a new pit; and 100 per cent of the plumbing permit fee. The City rebates the lesser of the maximum or the cost of the work, and the work and application must be done within 18 months of the permit's issue date. The City lists the program as currently under review: check ottawa.ca before you rely on it (checked September 2026).

If you sign at home, it is a direct agreement under the Consumer Protection Act, 2002, and one over $50 must be in writing and delivered to you. The prescribed contents include a fair description of the work, an itemized list of prices and the start and completion dates. You can cancel it for any reason within 10 days of receiving your written copy. If the contract includes an estimate, the final charge may not exceed it by more than 10 per cent.

The City lists "Damp proofing of existing basements" as work that does not need a permit. "Structural foundation repairs and drain tile replacement" is on its permit list, and the City says a permit is required to install protective plumbing devices such as a backwater valve or a sump pit and pump. Exterior membrane work without tile replacement, and crack injection, are not named on either list: ask the City's Building Code Services before the work starts.

On the City's 2026 fee schedule, a permit for plumbing work only is $117 per application. Other alterations are $12.75 per $1,000 of the assessed value of the work, with a minimum of $117, and the value includes materials, labour, overhead and professional fees. The protective plumbing rebate covers 100 per cent of the plumbing permit fee for eligible devices.

No. The City says designated heritage buildings, and buildings in a Heritage District Overlay, are not subject to the exemptions, so even work on the exempt list needs a check with the City first.

Ontario's Building Code makes dampproofing the default for a foundation wall below ground where the outside ground is higher than the floor inside, applied from finished ground level to the top of the footing. Waterproofing is required "where hydrostatic pressure occurs" (O. Reg. 163/24, 9.13.3.1). The Code gives no number for that, so ask the contractor which one the quote covers and why it fits your site.

Foundation drain tile or pipe must be at least 100 mm in diameter, laid so its top is below the bottom of the floor slab, and covered on the top and sides with at least 150 mm of crushed stone or other clean coarse granular material (O. Reg. 163/24, 9.14.3). It drains to a sewer, a drainage ditch, a dry well, or a sump with a pump.

At least 750 mm deep and at least 0.25 m² in area, with a cover designed to resist removal by children and made airtight (O. Reg. 163/24, 9.14.5.2). Where gravity drainage is not practical, an automatic sump pump is required.

We found no Ontario or City of Ottawa licence for waterproofing contractors. Plumber is a compulsory trade in Ontario, and the province says you cannot engage someone to do compulsory trade work unless they are authorized to do it, so ask who does the plumbing part of a backwater valve or sump job. The Skilled Trades Ontario Public Register is where homeowners can check.

Under the Consumer Protection Act, 2002, a supplier is deemed to warrant that services are of reasonably acceptable quality, and a contract term that tries to cancel that deemed warranty is void. Anything beyond it is whatever the contract says, so get the warranty terms in writing: what is covered, for how long, and whether they transfer to a buyer.

WSIB's clearance policy does not apply to a homeowner who lives in the house and directly hires a contractor for exempt home renovation work. You can still ask for one. A clearance is valid for up to 90 days, and without one a principal may be liable for the contractor's WSIB payments up to the value of the labour.

Yes. Ontario's locate law says an excavator, which includes an individual, may not dig until a locate request has been submitted and the utilities have responded. Locates are free. Ontario Dig Authority asks for the request at least 5 business days before you dig.

The City is responsible for the sanitary and storm laterals from the property line to the street; the homeowner is responsible from the property line to the house. The City names two cases where a lateral blockage is the City's to fix: when City-owned tree roots cause it, or when the damaged part is on City property.

The Building Code requires the storm sump discharge to have a union and a check valve and to be pumped to above grade level (O. Reg. 163/24, 7.4.6.3). The City advises connecting the sump pump to the storm sewer or discharging to the ground at least 1.2 metres from the foundation, and says foundation drains should not be connected to the sanitary sewer.

Check your own policy. Ontario says overland flood insurance is not automatically included in home insurance, and the province's insurance regulator suggests asking "Am I covered for sewer backup? If so, to what amount?" Ask your insurer in writing, and ask about seepage through walls separately.

No. The City's protective plumbing FAQ says these devices will not stop water from entering through cracks in walls or window wells, failed foundation drains or sump pumps, overflowing eaves troughs and plugged downspouts, poor foundation drainage, poor lot drainage, or water sources inside the house.

It is a $1,000 payment for basement flooding caused by sewer surcharging. The City says it is not provided for flooding from an appliance failure, a sewer lateral blockage, or overland flooding due to a foundation crack or leaking window well. The City lists the grant as currently under review, so check ottawa.ca for the current terms.