FAQ
Is a general contractor licensed in Ontario?
No. There is no provincial licence for general contracting or for renovation work. Some things inside a renovation are licensed: electrical and plumbing are compulsory trades with certificates of qualification, professional engineers are licensed by PEO, architects are registered with the OAA, and permit drawings generally need a designer registered with the Ministry holding a BCIN. A contractor who says they are licensed is usually pointing at insurance or a business licence, so ask which one.
What renovation work needs a building permit?
Structure, services and use. Changing structure, adding or moving plumbing, creating a new dwelling unit, adding a bedroom in a basement, and changing an opening in an exterior wall all need one. Replacing finishes in the same footprint generally does not. Confirm your scope with City of Ottawa building services before demolition.
Can I get the HST back on a renovation?
Almost never. HST is 13 per cent in Ontario and there is no general renovation rebate. The GST/HST new housing rebate only reaches a substantial renovation, which the CRA defines as removing or replacing 90 per cent or more of the interior of the house, or a major addition combined with that work. The CRA states that renovating a basement, or adding a garage or a deck, by itself does not qualify.
Does Tarion cover renovation work?
No. Tarion is the warranty on a newly built home from a builder licensed by the HCRA, with one, two and seven year periods. Its exclusions specifically name defects in materials, design and work supplied by the homeowner, and alterations or additions the homeowner makes. On a renovation your protection is the permit and inspections, a written contractor warranty, and the statutory holdback.
What is the ten per cent holdback and do I have to do it?
It is the statutory holdback under Ontario's Construction Act: ten per cent of the price of services and materials as they are supplied. It protects you if a subcontractor is unpaid and registers a lien. As of 1 January 2026 the annual release of accrued holdback is mandatory and follows a formal notice process, so ask a lawyer about the mechanics on any large project.
Does my contractor need WSIB coverage?
Usually yes. Coverage has been compulsory in construction since January 2013 for independent operators, sole proprietors, partners and executive officers. There is an exemption for work on an existing private residence retained directly by the occupant or a family member, but WSIB's own policy says it does not extend to subcontractors hired by the main contractor. Ask for a clearance certificate.
Do I need a permit to remove a tree for an addition?
Often yes. The City of Ottawa protects distinctive trees on private property, and its own landscaping guide puts the urban private-property threshold at 30 cm diameter. City-owned trees may not be touched at all, and their critical root zone, 10 cm of radius per 1 cm of trunk diameter, is protected during construction. Confirm your specific case with the City.
How much contingency should I budget?
Ten per cent on housing built after about 1990, and fifteen to twenty per cent on anything pre-war. Inside the Greenbelt the unknowns are old wiring, galvanised supply lines, plaster and lath, no subfloor, and stone or block foundations. None of those appear on a quote until the wall is open.