Renovating · Extension · Laval
Laval publishes the price and the delay of its extension permit: that is rare, and it lets you plan. Here is the seven-step process, the 2026 costs, and the extend-or-move calculation in your sector.
In Laval, extending a single-family home requires a building permit whose fee and delay the city publishes: $92 for the first $20,000 of work plus $2.50 per $1,000 or part of $1,000 above (a $120,000 extension therefore costs $342 in permit fees), an approximate delay of 50 days from the complete file, and connection fees ($450 for the first dwelling, plus $300 for work within the street right-of-way) only if the project touches the connections. Covered: adding a second storey, an integrated garage, a permanent attached carport, a sunroom or an attached veranda. The process has seven steps: check whether the property is subject to a site planning and architectural integration programme (PIIA) and to construction standards, prepare the application, file it online (or by appointment at 1333 boulevard Chomedey), pay, review, receipt of the permit by email, then the inspector's visit; the delay stretches with the season, complexity and any minor variance or PIIA. The cost of the work follows the 2026 industry ranges ($250 to $450 per square foot on a full foundation, $200 to $400 for a storey), $100,000 to $160,000 for 400 square feet; in the bungalow sectors of Chomedey, Vimont, Fabreville or Sainte-Rose, adding a storey is compared with sales of two-storey houses in the same sector to judge the value created.
| Item | Rule (laval.ca, extension of a single-dwelling home) |
|---|---|
| Building permit fee | $92 for the first $20,000 + $2.50 per $1,000 or part of $1,000 above (example: $120,000 of work, $342) |
| Connection (if connections are affected) | $450 for the first dwelling + $20 per additional dwelling; $300 more for work within the street right-of-way (1 to 4 dwellings); other fees possible under by-law L-11870 |
| Delay | 50 days, approximate, from receipt of all documents; longer with the season, complexity, a minor variance or a PIIA |
| Work covered | Adding a 2nd storey, integrated garage, permanent attached carport, sunroom or veranda attached to the residence |
| Steps | 1. PIIA and standards check; 2. preparation; 3. filing; 4. payment; 5. review; 6. permit by email and start of work; 7. inspector's visit |
| Filing | Online; otherwise by appointment at the urban planning department, 1333 boulevard Chomedey |
| Before digging | Locate request to Info-Excavation |
| Type of extension | Typical 2026 cost (Dessins Drummond estimates, August 2026) | Typical project |
|---|---|---|
| Ground-level extension on a full foundation (basement) | $250 to $450 per square foot | 400 sq ft at the back: $100,000 to $160,000 |
| Ground-level extension on piers or a slab | $200 to $390 per square foot | Cheaper, no basement |
| Second storey added on the existing house | $200 to $400 and more per square foot | 800 sq ft: $160,000 to $320,000 and more, depending on structure and roof |
| Attached garage | $180 to $240 per square foot | 400 sq ft: $72,000 to $96,000 |
| Four-season sunroom | $250 to $325 and more per square foot | 300 sq ft: $75,000 to $97,500 |
These ranges are industry estimates, before taxes, excluding plans ($2,000 to $8,000 depending on the architect or technologist), permits and contingencies (allow 10% to 15%); an extension that touches the roof, plumbing, electrical or load-bearing structure lands at the top of the range. Three detailed quotes from RBQ-licensed contractors, with a schedule and a holdback, remain the only way to get a price.
An extension is rarely recovered in full at resale: in a sector where comparable houses already have the added area, the value created comes close to the cost; in a sector of smaller houses, it caps at what the market pays for the best house on the street, and the excess is lost. The honest comparison: the cost of the extension (plus 6 to 14 months of work and municipal taxes that rise with the assessed value) against the cost of selling and buying bigger (commission, notary, welcome tax, moving: about 8% of the price, $50,000 to $60,000 on a $650,000 to $700,000 house) and the price gap between the two houses. A broker who knows the sector's closed sales can price both options within a week, before you pay for plans.
Yes, for any increase in floor area, including a storey, an attached garage, a sunroom or a veranda; the permit is obtained before the work and an inspector visits the site.
About $100,000 to $160,000 in 2026 for a ground-level extension on a full foundation, taxes, plans and permit extra, according to industry estimates.
Partly: the value created depends on the sector's comparable sales and caps at what the market pays for the best house on the street; compare with selling and buying bigger.
Six to fourteen months from plans to completion, including several weeks for the permit, longer if the project needs a minor variance or an architectural integration approval (PIIA).
Before extending, compare with the other option: the cost of selling, renovating before selling and the 2026 renovation grants.
The Loaa & Manseur team, led by Lotfi Manseur and Loaa Al Daow, is the number 1 team at RE/MAX Platine in 2024 and 2025, 6th RE/MAX team in Quebec, 15th in Canada and in the global top 50 of large residential teams according to the official RE/MAX ranking, computed on actual transactions. Its Google profile counts 221 reviews with a 4.9 rating. Its offices are at 55 avenue de l'Équinoxe in Brossard, one bridge from the island, and every broker's licence can be checked in the OACIQ public register. Three things to verify yourself before calling us, and to demand of any other broker.
Also available in French: version française de ce guide.
Published September 7, 2026 by the Loaa & Manseur team, the number 1 team at RE/MAX Platine in 2024 and 2025, 6th RE/MAX team in Quebec, 15th in Canada and in the global top 50 according to the official RE/MAX ranking. Tell us about your project.
Équipe no 1 de RE/MAX Platine en 2024 et en 2025, 6e au Québec, 15e au Canada et dans le top 50 mondial au classement officiel RE/MAX. Réponse en moins de 24 heures, sept jours sur sept.