A general home inspection is a broad assessment. For many properties, it’s sufficient. For others — older homes, rural properties, homes with specific systems or conditions — the general inspection should be supplemented by specialist assessments that go deeper into areas the general inspector can observe but not fully evaluate. Knowing which specialists to engage for which property types is how you close with confidence rather than crossed fingers.
“A general home inspection is like a physical exam from your family doctor. It covers everything at a general level and flags what needs more investigation. The specialists are the referrals — the cardiologist, the neurologist. For an older home, if the inspector flags potential knob-and-tube wiring or suggests the chimney needs a closer look, those referrals matter. Skipping them because you want the deal to close is taking a risk that might be small or might be enormous.”
— Colette Arseneau, certified home inspector and OAHI member with 21 years of experience in residential property inspection in the local area
Table of Contents
Specialist Inspections for All Properties
Radon Testing
What it is: Radon is a naturally occurring radioactive gas produced by the decay of uranium in soil and rock. It enters homes through foundation cracks and gaps. It’s colorless, odorless, and tasteless — and it’s the second leading cause of lung cancer after smoking.
Why it matters: Health your country estimates that approximately 10% of Canadian homes have radon levels above the guideline. There is no safe level — but levels above 200 Bq/m³ are considered actionable.
How it’s done: Long-term testing (90 days minimum, ideally over winter) is the most reliable method. Approved test kits are inexpensive ($30–$80) and can be conducted by the homeowner. Short-term tests (48 hours) are available but less reliable.
Cost: $30–$80 for a DIY long-term test kit; $200–$400 for a professional test by a certified measurement professional.
Bottom line: Radon testing is low-cost, non-invasive, and relevant to virtually every your region home. It should be done in any home purchase. If levels are high, mitigation systems cost $1,500–$3,000.
Specialist Inspections for Older Homes (Pre-1980)
Knob-and-Tube Wiring Assessment (Electrician)
When: Any home where the general inspector identifies active knob-and-tube wiring or wiring of uncertain age.
What it assesses: Whether the K&T system has been improperly modified, overloaded, or has insulation placed over it (a fire hazard). Whether active K&T will affect insurance eligibility and at what premium.
Why it matters: Many your region insurers refuse coverage or charge significant premiums for homes with active K&T. An electrician can assess the scope of K&T present, whether the modifications are problematic, and the cost of remediation.
Asbestos Testing (Environmental Consultant)
When: Any home built before 1990, particularly pre-1980, where renovation work is planned. Especially relevant if: floor tiles are vinyl (9″x9″ are nearly always asbestos-containing), textured ceilings (popcorn ceilings before 1980 often contain asbestos), or pipe insulation is present.
What it assesses: Whether suspect materials contain asbestos and at what concentration. Determines whether removal, encapsulation, or management in place is appropriate.
Why it matters: Undisturbed asbestos is not immediately dangerous. Disturbed asbestos (during renovation) releases fibers that are a serious respiratory health risk. Knowing what you’re dealing with before buying (and before planning renovations) is important.
Lead Paint Testing
When: Any home where children will live and where the paint is in deteriorating condition, particularly homes built before 1978.
Why it matters: Lead paint exposure causes developmental problems in children. Testing is straightforward — swab kits are available at hardware stores, or an environmental consultant can test. If lead paint is present, it needs to be managed (encapsulated or removed by a qualified contractor) rather than disturbed.
Chimney Camera Inspection (WETT Inspector)
When: Any home with a wood-burning fireplace or wood stove, or a chimney serving a gas or oil appliance.
What it assesses: Liner condition, structural integrity, creosote buildup, chimney cap and crown condition. The things the general inspector notes but cannot fully assess without a camera.
Why it matters: A damaged chimney liner can allow carbon monoxide to enter the home or combustion gases to reach combustibles — a fire and safety risk.
Sewer Scope (Plumber)
When: Any home more than 30 years old where the drain condition is unknown.
What it assesses: The condition of the main drain from the house to the street — looking for tree root intrusion, collapsed pipe sections, offset joints, or blockages that will cause expensive backups.
Why it matters: Sewer scope before purchase costs $200–$400. Main drain replacement after purchase costs $5,000–$20,000+. It’s one of the highest-value specialist inspections available.
Specialist Inspections for Rural Properties
Septic System Inspection
When: Any rural property with a private septic system.
What it assesses: Tank condition, baffle condition, leaching bed condition, system compliance with current setbacks. Best done by a licensed septic service company who pumps the tank during the inspection.
Why it matters: A failing leaching bed costs $15,000–$40,000 to replace. A septic inspection before purchase reveals current condition and remaining life.
Well Water Testing
When: Any rural property with a private well.
What it assesses: At minimum, bacteriological testing (E. Coli and total coliform). Expanded testing as appropriate for local geology and land use.
Why it matters: Well water quality is the buyer’s responsibility once they own the property. Testing before purchase reveals whether the water is safe to drink and whether any treatment is required.
Well Condition and Yield Assessment
When: Any rural property with a private well, particularly older wells of unknown depth or yield.
What it assesses: Well casing condition, pump age and condition, water yield (litres per minute).
Other Specialist Inspections to Consider
Mold assessment: If the general inspector notes visible mold, musty odors, or significant moisture issues, a mold assessment by an industrial hygienist identifies the scope and species of mold and informs remediation.
Structural engineering assessment: If the general inspector flags foundation concerns, significant cracks, or evidence of structural movement.
HVAC technician assessment: If the furnace is aging or the general inspector flags concerns about the heat exchanger.
Related Questions
- Questions to Ask a Home Inspector Before You Hire One
- What Does a Home Inspection Cover?
- Questions to Ask After a Home Inspection — Understanding the Report
- Questions to Ask a Septic or Well Service Company Before You Hire One
- Questions to Ask a Chimney or Fireplace Contractor Before You Hire One
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