The rule that decides whether a Laval roof works
Laval's Code de l'urbanisme contains a prohibition rather than a restriction: on a residential building, a solar panel cannot be installed at all on a roof slope connected to the front or the secondary front façade. Not set back, not flush mounted, not with a permit. Not installed. Every other rule about setbacks and heights applies to the slopes that remain.
The practical test is simple. Stand at the street and look at your roof. The plane you are looking at is out. If your house presents its long, unshaded, south-facing slope to the road, then the aspect that would have produced the most is the one Laval has excluded, and your options narrow to a rear or side slope with a worse orientation, a ground-mounted array, or no project. That is a legitimate outcome to reach, and it is far cheaper to reach it in ten minutes at the kerb than after two site visits.
Note that the prohibition names the secondary front façade as well as the front one. A lot with two street frontages therefore has more of its roof taken out of play than a lot with one, so a corner property should check both planes before assuming there is a workable aspect left.
Setbacks, heights and the ground-mount option
Where a roof panel is permitted in the front or secondary front yard area, it must sit at least 3 m back from the roof edge and stand no more than 2 m tall. Those two numbers are what an installer's layout has to be drawn against, and they tend to cost you the row of panels nearest the edge, which is often the least shaded row.
Ground mounting is a real alternative in Laval rather than a fallback nobody uses, but it carries its own dimensions: 3 m of setback from the front, 2 m from the secondary front, 1 m from side and rear lines, and a height limit of 1.8 m. A ground array at that height on a decent lot can be oriented and tilted freely, which is worth something when the good roof slope is unavailable.
Wall mounting is permitted but limited: a wall-mounted panel cannot project more than 0.6 m from the wall. And if your building is heritage listed, wall coverage limits are tighter again, so a listed property should confirm what area it is allowed to cover before designing around a wall.
None of these dimensions is negotiable at the quoting stage, so give them to every installer at the start. A design drawn without them is a design that will be redrawn.
What a Laval roof produces and what the power is worth
Natural Resources Canada puts Laval's photovoltaic potential at 1,194 kilowatt hours a year per kilowatt of installed capacity at optimal tilt. That is the ceiling figure for a well-oriented, unshaded array. A rear-slope array on a house whose best aspect faces the street will land under it, sometimes well under it, and the gap between the two is the real cost of the front-slope prohibition on a given property.
On the value side, Hydro-Québec bills residential customers on Tarif D, a two-tier block rate rather than a time-of-use rate. The first block of daily consumption runs at 7.065 cents per kilowatt hour as of April 2026 and consumption above the block costs more. Since there are no peak hours in Quebec, nothing is gained by shifting appliances around the clock, and the value of a solar kilowatt hour is simply the block rate it displaces.
Put those together and you get the sensible order of operations in Laval: establish which slope is legally available, work out what that slope can realistically produce, and only then size the system against your consumption.
Whose roof is it in Laval
Laval's dwelling stock is suburban and low-rise. 44.8 percent of dwellings are single-detached houses and a further 9 percent are semi-detached, so a clear majority of Laval homeowners own the roof over their own unit and do not need anyone's agreement to work on it. That is the single biggest structural advantage a Laval solar project has.
30.5 percent of dwellings are low-rise units and 9.8 percent are in high-rises, and in both cases the roof is common property or the landlord's. A semi-detached owner sits in between: the roof plane is typically shared with the neighbouring unit, so the array's footprint, the roof penetrations and any future roof work all become a conversation with the other owner before they become an installation.
Connecting to Hydro-Québec and sizing the system
Hydro-Québec is Laval's distributor, and grid-connected solar runs through its option d'autoproduction. A licensed CMEQ electrician files the installation request for you, and Hydro-Québec then evaluates whether the local network has capacity before granting a conditional acceptance. The 1,000 kilowatt ceiling on self-generation is far above any house, so the constraint on a residential project is time and address-specific network capacity, not size.
Surplus exported to the grid is credited one for one, in kilowatt hours, into a surplus bank that is drawn down against later consumption. The catch is that the bank is emptied every 24 months, on 31 March of each even year, and a balance standing at that moment is settled at Hydro-Québec's average cost of supply, well beneath the retail price you pay. The arrangement cannot produce a negative bill either, so there is no scenario where banking more surplus turns into money.
In most of Quebec the advice that follows is to resist oversizing. In Laval the front-slope prohibition often does that for you: a household that loses its street-facing plane frequently ends up with less capacity than its consumption would justify, not more. Either way the target is the same. Size to the annual consumption on your bills. If the available slopes cannot reach it, a smaller system that you consume entirely is still working at full value, because every kilowatt hour it makes is one you never buy.
Grants and financing for a Laval installation
Hydro-Québec's LogisVert solar grant pays $1,000 for each kilowatt of capacity you install, up to a ceiling of 40 percent of eligible project costs, which Hydro-Québec describes as typically $5,000 to $6,000 on a residential system. Because the grant is paid per kilowatt, a Laval array shrunk by the front-slope rule collects proportionally less, which is one more reason to establish the usable roof area before budgeting.
The timing conditions are strict. The installation has to be completed on or after 30 June 2025, and the application must reach the LogisVert portal within 9 months of the installation date. Hydro-Québec's own projection is that the grant pulls a typical residential payback from 25 to 30 years down to roughly 10 to 12, which is its modelling of a typical case rather than a number for your roof.
Federal help is thinner than it was. The Canada Greener Homes Loan, interest free up to $40,000, closed to new applications on 2 October 2025 and now funds only approved loans. The Canada Greener Homes Affordability Program replaced it in September 2025, delivering no-cost retrofits through provincial partners to low and median income households, with solar eligible federally but each province setting its own technology list. Canada offers no residential investment tax credit for solar.