Home Renovation Costs in Ontario: What Shapes Your Budget

Why renovation costs vary so much in Ontario

Ask ten homeowners what their renovation cost and you will hear ten very different answers, even for projects that sound similar. That is not because pricing is random. It is because a renovation is a custom project built inside an existing structure, and every home brings its own starting point. A 1960s bungalow in Scarborough, a 1990s two-storey in Markham and a new-build townhome in Vaughan will each respond differently to the same plan.

Rather than publishing numbers that would not reflect your home, this guide explains the variables that shape a renovation budget in Ontario. Understanding them will help you set realistic expectations, prioritise what matters most and read a contractor’s proposal with a clearer eye.

Scope levels: what changes and what drives the cost

The single most useful way to think about cost is by scope. Most projects fall somewhere along a spectrum from a cosmetic refresh to a full transformation. The table below compares the three broad levels by what typically changes and which cost factors tend to dominate.

Moving from one level to the next is rarely a small step. Once a wall opens, related work such as insulation, electrical updates and drywall usually follows, and that cascading scope is one of the main reasons budgets grow.

The core factors behind any renovation budget

Size and complexity of the space

Larger rooms need more material and labour, but complexity often matters more than size. A compact bathroom with a curbless shower, custom niches and relocated plumbing can involve more trade hours than a larger room with a simple layout.

Age and condition of the home

Many GTA homes were built decades ago and have been renovated in pieces since. Older wiring, galvanized or mixed plumbing, uneven framing, past water damage and outdated insulation can all surface once work begins. Homes of any age can hide surprises, but older ones generally carry more uncertainty.

Layout changes and structural work

Keeping plumbing, gas lines and load-bearing walls where they are is usually the most cost-efficient path. Moving a sink, relocating a toilet or opening a wall between rooms adds design, engineering, trade work and often permits.

Materials, finishes and fixtures

This is the variable you control most directly. Stock versus custom cabinetry, porcelain versus natural stone, standard versus designer plumbing fixtures: each decision can shift the budget noticeably. Finish level also affects labour, since some materials take longer to install well.

Mechanical, electrical and plumbing systems

Renovations often trigger upgrades to the systems that serve the space, such as new circuits for appliances, improved ventilation, relocated ductwork or updated supply and drain lines. These items are not always visible in the finished room, but they matter for safety, comfort and long-term performance.

Permits, drawings and inspections

In Ontario, building permits are issued by your local municipality, and each sets its own process. Structural changes, new or relocated plumbing and the creation of new living space commonly require a building permit, while purely cosmetic updates often do not. Permit applications may require drawings or engineering, and inspections add steps to the schedule. Electrical work is handled separately: Ontario’s Electrical Safety Authority (ESA) generally requires a permit for most electrical work. RENAWO reviews permit needs with you during planning so they are reflected in the scope from the start.

HST and other costs that are easy to overlook

Harmonized Sales Tax (HST) generally applies to renovation services and materials in Ontario, so it is worth confirming whether any figure you are comparing includes it. Other items that are easy to miss include disposal and bin fees, temporary protection of floors and finished areas, appliance delivery and installation, design fees and, for larger projects, the cost of living elsewhere during construction.

Budgeting and contingency

A realistic budget has three parts: the planned scope, your selections, and a contingency for things nobody can see yet. Many homeowners plan a contingency of roughly 10 to 20 percent of the project budget, leaning toward the higher end for older homes or projects that open walls and floors. Treat that figure as a general planning habit rather than a rule; the right amount depends on your home and how settled your design is.

• Separate needs from wants. Rank your priorities so you know where to adjust if conditions change.
• Make selections early. Decisions made before construction starts are far easier to price accurately than choices made on site.
• Ask what is included. Compare proposals line by line, including allowances, permits, disposal and taxes.
• Protect the contingency. Use it for genuine unknowns rather than upgrades, and decide on upgrades separately.

Factors that commonly cause cost changes

Even a well-planned renovation can change once work begins. These are the most common reasons:

• Hidden conditions: rot, mould, past water damage, pests or previous unpermitted work found behind walls or under floors.
• Structural findings: undersized joists, notched framing or settling that needs correction before finishes go in.
• Plumbing and electrical updates: older wiring or piping that cannot reasonably stay once it is exposed.
• Permit and inspection requirements: items an inspector requires, or drawings needed before work can proceed.
• Lead times: special-order cabinetry, tile or fixtures that arrive late can disrupt trade sequencing.
• Design changes: changing a layout or selection after work has started usually costs more than deciding during planning.