The CAN/CSA A770-16 Home Inspection Standard explained

In February of 2019, the Ontario Association of Certified Home Inspectors chose to adopt the Canadian Standards Association CAN/CSA A770-16 Home Inspection Standard.

All members of this association have 12 months from February of 2019, to transition from their existing standard to the new CSA Standard.

What does this mean for both the Consumers and the Inspectors?


From a Consumer standpoint, it means that all OntarioACHI Inspectors, for all inspections requested by Buyers or Sellers as part of a Residential Sale process, will be required to perform inspections to a Canadian Nationally recognised and independently developed standard.

Unlike previous standards, however, the CSA standard is a protected document and normally requires a $50 (plus tax) payment to be reprinted.  The CSA has provided a consumer-facing, view-only version which requires registration on the CSA site.  The registration process is a little complicated and we are working with the CSA project team to identify ways in which consumer information can be more easily obtained.

For consumers, and inspectors who want to access the read-only version you can register here:


First and foremost, we strongly recommend all inspectors purchase their own copy of the standard which can be obtained here:

We have posted an example contract that Inspectors can use, that identifies the use of the CAN/CSA A770-16 standard, which can be found here
Now we need to take a look at how the new standard provides better guidance to the Home Inspection process and the resultant report.

First of all, the document is 30 pages long, with the first 7 (seven pages being made up of pre-amble about the CSA, Standards Council of Canada, the process by which standards are formulated, the team that developed these standards and a general index.

The actual standard starts on page 8 with a General Introduction to the standard, who the expected users are (Professional Home Inspectors) who are the beneficiaries of an Inspection performed to these standards (clients of the Inspectors who are purchasing or selling a home) and the definition of a Home Inspection.

Definition of a Home Inspection

The definition of the Home Inspection is along the lines of the definition that is provided for in almost every other standard that has been in use since the inception of the home Inspection Standard. 

This says that the home inspection “is intended to be a non-invasive evaluation of the condition and performance of systems and components of a home” and is focused on “significant issues that are readily visible to the inspector as opposed to minor building deficiencies”.   The inspection will be primarily performed “to identify and report any items that do not perform their intended function”. 

Under the minimum requirements of this standard, as per other standards, already in place, the A770-16 standard does not include “cosmetic, maintenance, and other non-critical items” and inspections carried out to this standard “are not intended to verify a home’s compliance to codes and regulations (e.g., building codes)”.

So from a general overview of the Home Inspection and it’s definition, the A770-16 standard does not substantially alter the current definition or general scope of a Home Inspection.

Inspectors can provide additional services, such as InfraRed thermal imaging, Radon measurements, Septic and WETT inspections and mould or other indoor air quality examinations, but these MUST be identified as separate services and bargained for through e.g. a contractual agreement.

General Conditions and Exclusions

Like prior standards, there are specific conditions to which the standard applies.  There are also specific exclusions listed.  The Standard, however, is based on the predication that, if something is not specifically identified as required in the standard, then it is by de-facto principle considered excluded from a Home Inspection.  This does not mean that a Home Inspector cannot choose to go beyond the standard and include items in the standard.  Again the standard requires that if this is the case, then these should be declared as part of the contractual agreement.

A term that is used throughout the standard is “The inspection shall include, but not be limited to…“.    This is a prime instance of where the minimum standard requires a component to be inspected, examined or reported on but leaves the inspector open to, at their discretion, go further if they deem it necessary.   It does not mean that just because the item is not specified, everything else that might be included is mandatory.

With respect to the extent over an above the minimum standard, a home Inspector is prepared to operate is a choice of either the Inspector.   Home Inspector Associations, such as ourselves, may choose to supplement the minimum standard with extra items to be considered as “in-scope” by default, that we require certified members to comply with.  Members of such an association will be required to comply with these standards and have a contractual agreement which identifies such.

A Home Inspector or a home Inspector Association should not able to provide a standard, to be used by Inspectors for clients of the Inspectors who are purchasing or selling a home, that offers a service inferior to those published in the CSA A770-16.

The A770-16 standard itself excludes inspections of industrial, commercial, or institutional buildings or common elements in condominiums, strata plans, although common elements could be included by contract as desired, at which point they must be performed in accordance with the requirements of the relevant clauses of the A770-16.

The standard has specific exclusions, as with all the prior standards but to emphasise the fact that these are typified and applicable to all inspected components that are highlighted at the beginning of the A770-16 standard.   These exclusions cover obvious items such as prediction of future events (probability of failure, remaining service life, etc.) determination of causes for conditions occurring or methods required to, and costs associated with, remediation, determination of suitability of use or advice on whether the property is worth buying or its value or determination of operating costs of any item or the property as a whole.

Also excluded for the inspection requirements are, sensibly, things that can’t be seen at the time of the inspection, including hidden, covered, enclosed or underground items or infestations of vermin, pests. or wood destroying organisms (WDO).   Visible indications of the possible existence of vermin, pests or WDO that are apparent to the inspector at the time of the inspection should, however, be reported on.

The areas of inspection

Similarly to other standards, the A770-16 standard covers specific areas that must be inspected as part of the Home Inspection.  These are specified as:

  • The Exterior to the Property (surrounding) including
    • Driveways, walkways, on-ground ramps, porches, patios, decks, and balconies
    • Fences
    • Exterior stairs
    • Retaining walls and constructed planters
    • Site drainage and grading
    • Swimming pool areas (for safety)
    • Automatic irrigation systems
  • The exterior of the property itself (Building Envelope), including
    • Exterior walls
    • Decks, balconies, pergolas, trellises, and similar structures
    • Exterior guards and handrails
    • Electrical Service entry
    • Exterior doors
    • Exterior windows and skylights
    • Roof (visible structure) and covering
    • Soffit, fascia, and trim
    • Gutters and downspouts
  • Visible Structure including
    • Foundations
    • Concrete slab on ground/grade
    • Floor structure
    • Wall structure
    • Roof structure (attic)
  • Interior finishes and built-in or attached furnishings including
    • Floors, walls, ceilings, interior doors, glazing, and trim
    • Attached cabinetry and countertops and built-in or attached furnishings
    • Interior guards and handrails
    • Interior stairs
  • Plumbing systems and components including
    • Potable water supply and distribution
    • Non-potable water reuse supply and distribution (grey water systems)
    • Domestic water heaters
    • Plumbing fittings and fixtures and bath and shower enclosing surfaces
    • Interior sanitary drainage systems
    • Storm drainage systems
    • Non-potable water discharge systems
  • Heating, cooling, and mechanical ventilation (HVAC) systems including
    • Insulation, air barrier, and vapour barrier
    • Heating and cooling systems (furnace, boilers, compressors, etc.)
    • Mechanical ventilation systems
    • Fireplaces and chimneys
  • Electrical systems
    • Electrical service, main disconnect, and earth grounding system
    • Distribution panels
    • Distribution wiring and circuitry
    • Lighting, switches, receptacles, and junction boxes
    • Auxiliary and other electrical systems
  • Life/safety systems, including
    • Garage doors and openers
    • Carbon monoxide detection
    • Smoke and heat detection
    • Fire separation and egress
    • Accessibility equipment

Most home inspectors that are complying with one of the recognised standards will be performing inspections almost compliant to these items already.    The only additions to the prior standards for areas to be inspected are the Grey Water and Irrigation systems, Accessibility Equipment, Swimming pool safety, exterior recreational structures and fences.


An area of the A770-16 standard which may require some Inspector to change their mode of operation is in the area of reporting.   Reports are required to be more detailed, better explained and easier to identify the components, their locations, the identified concerns and the defects.  The reports should include annotated photos and images to assist the consumers to understand the findings.

This will essentially eradicate what is known in the profession as the “tick-guess” report.   As a written report is also mandated, verbal reporting and walk-through inspections where the client or realtor is expected to take notes will also not be allowed.

The reports must also include what component is not inspected, and a reason why. 

This reason cannot be because the scope of the inspection the inspector offered did not include the component or area of the standard as part of the inspection.

For inspectors already using HomeGauge, Home Inspector Pro or Horizon, the changes to your templates to adapt them for the CSA-A770-16 standard will be minimal.

e.g.  The CSA standard requires you to add who is at the inspection, what the grade of the property is, type & style or home, weather conditions, ground conditions, the approximate age of the property, all standard in the CSA templates for HomeGauge, HIP and Horizon.

OntarioACHI will be releasing a series of custom templates over the coming months that provide a template not just for the A770-16 minimum standard but also options that allow inspectors to provide extra services above and beyond those services in a controlled and standard fashion.  This will increase the protection for the consumer over and above that already established by this standard.

These templates will include standard responses and additional images to explain the proper workings of a home.


A number of tools are expected to be used by a home inspector as part of the inspection process according to the standard.   This may require the use of the following tools that are not currently used by inspectors.

The standard mandates “The home inspector shall provide all equipment and tools required to conduct the home inspection”.  This may include:

  • binoculars,
  • magnifying photography
  • borescope
  • tape measure
  • laser measure
  • digital thermometer
  • electrical circuit analyzer
  • voltage detector
  • spirit level
  • moisture meter

Where the inspector considers the use of a tool a specialized need and outside of the scope of the standard these areas should be reported upon in the report.   This is again specified in the Standard:- “Suspected or potentially hidden conditions that can only be identified through destructive testing, with the use of specialized tools or equipment, or that are the domain of a specialist should be reported along with a recommendation to the client to investigate further where the condition could be of an urgent nature.

Although this is in the non-mandatory section of the standard we believe this is good practice. 

Notes of Caution

The A770-16 Standard does not provide a “how-to” inspection guideline so it is primarily up to the inspector to ensure they are properly trained to perform the inspections, recognised defects correctly and comprehensively report on them.

As an association, we will continue to support and give guidance to inspectors about the best way to carry out their duties.

Above all, Inspectors are reminded that even prior to regulation, a number of activities performed by inspectors are already covered by regulations.

Going further still.

OntarioACHI has a training course for Inspectors as well as a presentation that explains the new A770-16 standard to Realtors and Consumers.  We are just waiting for approval from the various bodies to release these.  We will notify members when these are ready for release and distribution.