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Exterior & Drainage · Bones (mechanical)

Retaining walls

A wall that holds back soil, and holds back water pressure with it. On sloped lots the retaining wall can quietly be the most expensive "landscape" element on the property, and walls above roughly a metre generally need engineering and permits in Ontario municipalities.

$1,500 to $5,000 repairs; $5,000 to $15,000+ rebuild; engineering $1,500 to $3,500Address soonExteriorStructure
The ten second check

What else is typical in a house this age?

You are reading the retaining walls page. Type the year the house was built and I will tell you what else tends to be true at that age, what it costs, and what to ask. One number, ten seconds.

A guess is fine. 1965, or just the 60s.

Anything worrying you? Tap any that apply, or skip it.

Free. No account. Educational and impartial, not a home inspection.

Why it matters

A leaning or bulging retaining wall is soil pressure winning, the same physics as a bowing basement wall, outdoors. A failing wall that supports the driveway or a neighbour's grade is a liability item, not landscaping. Rebuilds run $5,000 to $15,000+ before engineering.

How to spot it

Sight down the wall's length, lean and bulge show up immediately. Look for stair-step cracking through block or stone, slumped or separated sections, rotting railway ties, soil washing out at the base, and no weep holes or visible drainage on a tall wall. Note the wall's height against a person and whether it sits on the property line (whose wall is it?).

What it costs

Repairs $1,500 to $5,000; replacement $5,000 to $15,000+ depending on height, length, and material; engineering runs $1,500 to $3,500 when required.

What to do

Address soon if leaning: get a landscape/structural contractor's assessment before the freeze-thaw cycle moves it further, and ask who owns a boundary wall before assuming the cost is yours, or the neighbour's.

Education and triage, not a home inspection. Casaroo flags lean, bulge, and drainage tells from your photos. Whether a wall needs engineering is a height-and-site question your contractor or municipality answers.

Common questions

Whose wall is it if it sits on the property line?

That is the first question to answer, and it is a lawyer question. A boundary wall can be shared, and assuming the cost is the neighbour's, or that it is yours alone, is how people get surprised. Ask before you assume.

Is a leaning retaining wall urgent?

It is soil pressure winning, the same physics as a bowing basement wall, and Canadian freeze-thaw moves it further every year you wait. A rebuild runs $5,000 to $15,000+, so getting a contractor's assessment before the next winter is worth doing.

Does a retaining wall need engineering and a permit?

Walls above roughly a metre generally do in Ontario municipalities, and engineering adds cost on top of the build. Your contractor or municipality confirms what your specific wall and site require.

Will a general walkthrough cover retaining walls?

Generally only as a visual note, if at all. If a wall is tall, leaning, or supporting a driveway or a neighbour's grade, ask for it specifically or bring in a landscape or structural contractor.

Sources

Casaroo flags, it does not inspect.

Last reviewed 2026-07-10. This guide is general education, not a home inspection and not advice for your specific property. Always consult the appropriate licensed professional, and get a licensed home inspection before you remove conditions or buy. Cost ranges are 2026 estimates that vary by region, size, and access; confirm specifics with a qualified professional.
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