Ottawa has one of the best collections of pre-war housing in Canada, and buying one is a genuinely good idea — these buildings were constructed with materials and craftsmanship that are simply unavailable now. But a 1912 house in the Glebe is not a 2012 house with more character. It is a different building, built to different assumptions, and it fails in different ways.
The renovation is usually the problem, not the house
This is the single most important thing to understand. The original 1910 construction — solid masonry, old-growth framing, generous joist sizing — is rarely what generates findings. It is the 1978 basement, the 1994 addition and the 2016 open-concept main floor. New finishes over old deficiencies. Beams carrying loads nobody calculated. A modern panel feeding original circuits. Insulation blown over knob-and-tube.
So the inspection question in a century home is not "how old is it" but "what has been done to it, by whom, and was it permitted".
The four questions your insurer will ask
Ontario insurers underwrite older homes on four systems. Get the answers during your conditional period, not after.
- Roof — material and age. Anything past twenty years invites questions; past twenty-five invites a deadline.
- Electrical — service size, panel type, and branch wiring. Active knob-and-tube causes many insurers to decline outright. A 60-amp service is usually a condition of coverage.
- Plumbing — supply material. Galvanized steel is a red flag; so is poly-B in a later-renovated home.
- Heating — type, age, and whether there is an oil tank, above or below ground. Buried tanks are a serious environmental and insurance issue.
Foundations: stone, brick, and early concrete
Rubble stone foundations have held Ottawa houses up for well over a century and a stone foundation is not, by itself, a defect. What matters is:
- Mortar condition. Historic lime mortar is soft by design — it lets the wall breathe and move. Repointing with hard modern Portland mortar traps moisture and damages the stone. Inappropriate repointing is worse than no repointing.
- Parging that hides things. A smooth cement coating over an interior foundation wall is very often a cosmetic answer to a water problem.
- Active water entry. Efflorescence, staining, spalling and rot at the sill are the evidence.
Structure: balloon framing and what people removed
Pre-1930 houses were commonly balloon framed, with studs running continuously from sill to roof and no fire-stopping at floor levels — meaning a basement fire has an open path to the attic. It is not correctable without opening walls, but it is manageable with interconnected alarms and awareness.
The bigger structural question is subtraction. Open-concept renovations remove walls that were doing work. Look for sagging above removed walls, sloping floors, and doors that will not latch. An inspector should be able to tell you whether a beam looks appropriately sized and properly supported to the foundation, and when the answer needs an engineer.
Materials worth screening for
- Vermiculite insulation — loose, pebble-like, often greyish-brown in attics and wall cavities. Vermiculite from the Libby, Montana mine may contain asbestos, and Health Canada advises assuming it does unless tested. Do not disturb it.
- Asbestos in other forms — pipe and duct wrap, vinyl floor tile and its adhesive, some plasters and textured finishes.
- Lead — in paint pre-1960, and in service lines. The City of Ottawa has a program for lead service replacement; check whether the address is affected.
- Buried oil tanks — on properties converted from oil decades ago. Remediation of a leaking tank runs into six figures in a bad case.
What not to worry about
Century home buyers routinely panic about the wrong things. Uneven floors in a 110-year-old house are usually history, not failure. Fine plaster cracking is normal. Original wavy glass is a feature. A stone foundation with sound mortar and a dry basement is doing fine. Old growth framing is generally stronger than what is used today.
Spend your worry on water, wiring, heat and structure — and on whether anyone pulled a permit.
Frequently asked
Is it a bad idea to buy a century home in Ottawa?
No. They are well built and in the best locations in the city. They need a more thorough inspection, an insurance conversation before you commit, and a realistic maintenance budget — but the buildings themselves are frequently sounder than what replaced them.
Will insurance cover a house with knob-and-tube wiring?
Many Ontario insurers will not write a policy on a home with active knob-and-tube, and those that will may require replacement within a set period. Ask a broker before your condition period expires, not after.
How much more does a century home inspection cost?
Typically $50 to $150 more than a standard inspection, because it takes an extra one to two hours and a different depth of investigation. It is the cheapest part of buying one of these houses.