Want to add a floor to your home? The specialists at Construction Précellence are here to teach you more about the factors that can influence the price of such a project! Do not hesitate to contact us for more information or for a quote request!


Adding a floor is a big project and requires a lot of thought. But the first question that comes to mind is: how much will it cost? The specialists at Construction Précellence have come up with a few tips that can help you make an informed decision about your floor addition project.


What are the elements that can influence the price of a floor addition?

  • Level of complexity of architectural integration
  • Modifications and reinforcements (if required) to the existing structure
  • Degree of difficulty in joining the new construction to the existing one
  • Work to be done on the existing building to perform the work
  • Access to the work site
  • Choice and quantity of doors and windows
  • Choice of materials

What is the average price of a floor addition project in Côte Saint-Luc?


  • Adding a floor above a first floor (+/- 1000 sq. ft.): for 3 or 4 bedrooms and a bathroom, costs start at around $225,000 and average around $250,000. Allow for additional budget for interventions on the first floor (except for the staircase which is included) and other project specific details.
  • Adding a floor (+/- 1000 sq. ft.) above a floor to make a 3rd floor plus the basement level: The base price is $300,000 and the average is around $350,000
  • Adding a floor above a garage or other room (+/- 300 sq. ft.): The base cost is generally $110,000 and the average is around $125,000. Note: in some cases, costs are between $125,000 and $150,000
  • Half-storey addition over a main floor (+/- 600 sq. ft.): The price starts at around $175,000 and averages around $195,000.
  • Addition of a room (mezzanine style) above a flat roof level (+/- 300 sq. ft.) with a roof deck: costs start at around $200,000 and average around $250,000.


All of the above prices include complete interior and exterior finish work from the first floor ceiling or the floor below. Below this level, only the staircase (if required) connecting the two levels is included.


We perform floor additions in residential settings only. Here is an overview of the places where we can do renovation work.

  • Single-storey house / single-family home
  • Cottage (two-storey house)
  • Semi-detached / Townhouse
  • Apartment, dwelling
  • Bi-generational and intergenerational house
  • Duplex, triplex, quadruplex
  • Luxury house / High-end house


Why choose Construction Précellence for your floor addition?

  • Company established since 1948
  • Choice of quality materials according to the client’s budget
  • In-home consultation with a professional designer
  • Price estimate for your construction and renovation project
  • Measurements taken by your designer
  • Plan and 3D model and follow-up of the manufacturing of the elements
  • Delivery and installation of the material
  • Quality of workmanship and superior knowledge
  • Respect of the highest standards in terms of cost control
  • Strict adherence to deadlines and the established budget
  • Protection and cleanliness of the work site
  • Management of permit applications with the city


Any questions?

If you have any questions about the price of a floor addition, or about our other services, do not hesitate to contact us by email, by phone, or to come and meet us in person at our offices in Montreal. Our team will be happy to welcome you and give you all the information you need.