Home Addition Cost in Toronto vs. Montreal: 2026 Guide

Are your living quarters feeling cramped? Do you find yourself dreaming of an extra room or a whole new level to expand your space? Next thing you know, you’re setting these home addition plans in motion, looking at options and prices. If you want to take on this kind of home improvement project, we’re here to provide answers to some of the most pressing questions you may have. 

This article will focus on costs for a home addition project in Montreal or Toronto, but we will also expand on the following questions: 

• What you need to know about home addition permits and regulations.

• Hidden costs that people often forget to take into account for this type of project.

• What are the zoning laws you need to know about?

• Whether you can build a home addition on a multiplex (specific to Montreal).

Home addition project : How much does it cost (Montreal vs. Toronto)

Source : VITRERIE ADSTOCK

Whether you live in Montreal or Toronto, building a home addition is a huge project. That being said, if it means not having to find a new house, sell your current abode, and move out, it can be worthwhile. 

Here are the current budget implications for a home addition project.

Home addition cost in Montreal

There are many different types of home addition projects, so we can’t give you one specific number right here and now as to how much your own project will cost in the end. However, we can look at the different average amounts for the most common home expansion projects.

Types of homes in Montreal

In Montreal, most of the real estate pool is made up of multiplexes, condo buildings, and single-family homes (bungalow, split level, shoebox). The majority of home additions are built on single-family homes, but an expansion can also be added on a multiplex. There are strict regulations that address which buildings can be expanded and how. 

For example, the approved home addition design has to be adapted to the size of the land available (many Montreal homes have little to no yard space). There are also specific bylaws for patrimonial buildings (e.g. : shoebox homes in certain areas). Lastly, some permit requirements can vary depending on the borough where you live. 

It’s highly recommended that you look into these bylaws and validate current permit requirements before you greenlight any home addition project. If you’re having a hard time figuring out what applies to your situation, hire an experienced general contractor or an architect to carry out your project. 

Check out this page from the city of Montreal’s website to get yourself started 

How much does a permit cost for a home addition in Montreal ?

This amount will depend on the project cost, based on the following calculation : cost of the work ÷ 1000 x $9,80. For example, if you plan to spend $200 000 on your home addition project, your permit would run you at least 1960$. 

It should be noted that extra fees may be added in certain cases, for example, if your home holds heritage status. All permit fees are non-refundable. 

If your project goes on past the planned timeline, you will have to apply for a permit renewal (before your permit expires). This process costs 25% of the original amount. 

How to get a home addition permit in Montreal

You can apply for a building permit online or in person. This page will also provide information about the documents needed to obtain the permit. 

Home addition cost in Toronto

Source : Architecture & Design Mario Fortin

If you’re looking to build a home addition in the 416 area, we’ve gathered some useful information in the following paragraphs.

For starters, here are the average prices of home additions in Toronto: 

Types of homes in Toronto

Toronto’s real estate pool is quite diverse, with lots of condos, townhouses, duplexes, detached homes, bungalows, and semi-detached homes. As is the case in Montreal, home additions are most often built on individual homes. However, they can also be added onto duplexes, triplexes, and in some cases, onto row homes. 

Of course, there are lots of municipal bylaws and regulations to look into before you even think about going ahead with a project. Contact your local authorities for specific and up-to-date information, including current zoning bylaws.

How much does a permit cost for a home addition in Toronto?

The total amount you’ll have to pay for a home addition permit in Toronto will depend on a few factors. There are base costs for any permit application and subsequent figures that vary depending on the size of the project. 

This is the formula used to calculate permit costs for a home addition (effective January 2026): 

Fee Calculation Formula:

• Permit fee = SI x A + base fee ($214.79)

• SI = Service Index for classification of proposed work ($18.56 per square meter.)

• A = Floor area in m2 of work involved of work involved

Based on this information, if you are building a 40 square meter addition,  that makes for $18.56 x 40 = $742.40, so your permit will cost a total of $957.19 ($742.40+ $214.79). 

Note that an hourly fee of $92.79 will be added if an inspection is required. Also, if you add a separate housing unit (e.g. : basement apartment), you’ll have to pay an extra fee.

How to get a home addition permit in Toronto

You can apply for a home extension permit online on Toronto’s municipal website. Be sure to include all the required documents and expect to hear back within a few weeks, up to several months depending on the size of the project. 

Home addition project costs : what to take into account

We’d love to affirm that home addition projects are simple; however, such is not the case. There are simply too many things to take into account and too many steps to carry out before the project is completed. While we’d love to give you a specific number of what you’ll end up paying, this is simply not possible. 

When calculating your budget, be sure to include a contingency fund that represents about 15-20% so you’re able to carry out the project even if unexpected costs pile up.

The hidden costs of a home addition project

Lots of things will have to be included in your renovation budget, from materials to labour, planning, cleaning and designing. Here is as complete of a list as we can provide, showing hidden costs applicable to the vast majority of home addition projects : 

• Land Surveying and preparation (excavation, grading, moving trees, demolition). 

• Updating HVAC, plumbing and electrical systems.

• Permit fees.

• Hiring an architect, technologist, and/or general contractor to oversee the project.

• Working with a structural engineer to ensure that the project is feasible.

• Having to strengthen the foundation.

• Other labour costs (all trades involved, from plumbers to electricians, painters, flooring specialists, tiling experts, carpenters, etc.)

• Finding the right materials to match the rest of the house (siding, roofing, windows, doors). 

• Encountering issues that come up when demolition starts (problems with the roof, structure, foundation, presence of asbestos, lead or mold). 

How to plan a home addition project

Source : Groupe Beaulieu construction

List of things to take into account for a home addition project

This is what you should be thinking about for a home extension project : 

• How much your budget would be.

• Why do you want to build a home addition?

• What are the zoning laws in your area for this type of project?

• How much time do you have to carry out the project?

• Would it be more worthwhile financially to build the addition or to buy a new home?

• What type of home addition do you prefer?

Here are some of our other articles about home addition projects for you to check out as you start planning out your project : 

Home Addition: How to Build it | Reno Quotes

Home Extension or Addition—How to Plan It Successfully?

Home Addition or Extension—What Are the Key Steps? 

Home Extension or Addition: Project-Specific Costs

Building a New Floor on a Home : What You Should Know 

How long does it take to carry out a home addition project ?

On average, a home addition project will require between 3 and 6 months. In most cases, this will be enough time to carry out each of the steps required to build a high-quality home extension. The duration of the project will depend on several factors including: 

• Permit delays.

• Availability of the materials.

• Contractor schedules.

• If the project is complicated to carry out. 

• How big the home addition is.

• What type of home addition is being built.

Use our home addition checklist to get organized : Home Addition or Extension Guide - Project Checklist

Who can legally carry out a home addition project ?

It depends on where you live. In the province of Quebec, contractors must have a valid license with the Régie du Bâtiment du Québec. If you are working with a general contractor, be sure to check their general contractor license on the R.B.Q. website. On the other hand, if you decide to oversee the project yourself, you’ll have to hire each trade separately and check their licenses individually. 

In Ontario, some trades require licenses or certificates of qualification, whereas others are free to carry out their work without a license. If you want to work with a general contractor, you’ll have to look for one with a valid license issued by the Home Construction Regulatory Authority (HCRA). 

Can I get financing for a home addition project in Toronto ?

There are lots of financing options for home renovation projects in Toronto. Here are a few things to look into : 

• Personal savings and credit cards.

• Getting a personal loan.

• Getting a line of credit.

• Securing a second line of credit + home equity loan.

• Refinancing your mortgage. 

• Applying for grants and subsidies.

Be sure to look into all the grants and subsidies currently available through the different levels of government : federal, provincial, and municipal. Each of these have various programs on offer at all times to favour spending on home improvement projects.

How to get financing for a home addition project in Montreal ?

Much of the same advice written above applies to financing a home in Montreal, from refinancing your mortgage to getting credit lines, personal loans and applying for grants and subsidies available through the government. 

Be sure to check with the city of Montreal, the province of Quebec and the federal government of Canada for any programs currently available to help you save money on your home addition project. 

Here are a few programs that could help as we write these lines : 

Home Renovation Financing - What Are Your Options?

Montréal Renovation Grants - What Programs Are Available?

Ontario’s 2025 Home Renovation Savings Program

Subsidies and Tax Credits for Renovations in Ontario

Where to find home addition contractors in Montreal

No need to look any further! We are here to help you find a certified home addition contractor covering the Montreal area. Simply fill out the form on this page and we’ll put you in touch with someone who is part of our select network.  

Where to find home addition contractors in Toronto

Don’t know where to start looking for professional home addition contractors based in Toronto ? We’ve got you covered. Start by filling out the form right here, tell us a bit about your project and we will put you in touch with qualified experts.