Raised, low or canopy: which solar structure suits your roof?

The structure is the part of a solar system you will live with most. It decides whether you can still use your roof, how the panels face the sun, and whether everything stays put through 25 years of summer storms. On the flat RCC roofs common in Mohali, Zirakpur and Kharar, there are three choices: a low frame, a raised frame or a canopy. This guide sets out what each one suits and what to check before you agree to one.

Low frame

The panels sit close to the roof, typically with the low edge a short distance above the slab, tilted towards the south.

• Suits: a roof you do not need to use, or a separate part of the roof set aside for the panels
• Cost: the lowest, because it uses the least steel
• Wind: the least exposed, so the frame and anchoring can be lighter
• Drawbacks: the roof underneath is lost; shadows from parapets, water tanks and stair rooms fall directly on the panels; and leaves and dust collect around the frame

Raised frame

The panels sit on columns high enough to walk under, so the roof stays usable below for water tanks, drying clothes or sitting out. This is the structure most Tricity homes choose.

• Suits: homes that use the roof, and roofs where parapets and tanks would shade a low frame
• Cost: higher, mainly for the extra steel and the footings
• Wind: the panels form a large surface well above the roof, so columns, bracing and footings must be designed for the wind load
• Advantages: clears most rooftop shadows, shades the roof slab, which keeps the top floor cooler, and leaves room to reach the water tank and the drains

Canopy

A canopy is a designed structure over a terrace, a parking area or a courtyard, which gives shade as well as power. It is usually built to look finished from below, with neater columns and a cleaner underside.

• Suits: kothis and larger homes with a terrace, porch or parking area that would benefit from cover
• Cost: the highest of the three, because it is designed as a piece of the building
• Rain: standard panels leave gaps between them, so rain comes through. A canopy meant to keep the area dry needs sealed joints or a sheet underneath, which should be agreed at the design stage
• Panels: bifacial panels suit a canopy over a light floor, because they also collect light from below. Our guide to panel types explains the difference

At a glance

What the structure should be made of

Under PM Surya Ghar, the approved materials for mounting structures are hot-dip galvanised steel or iron, aluminium, and since May 2026, ZAM, a zinc, aluminium and magnesium coated steel. Steel sections should conform to IS 2062 and the galvanising to IS 4759.

Hot-dip galvanised steel is the usual choice for raised frames and canopies, because of its strength. Aluminium is lighter and does not rust, and is often used for low frames and on sheds. Avoid structures painted rather than galvanised, and ask what happens at cut ends and drilled holes, where rust starts.

Wind, height and the footings

The structure should be designed for the local wind speed under IS 875 (Part 3), the Indian standard for wind loads, and Tricity’s pre-monsoon storms are the real test. A steeper tilt and a higher frame both increase the load. Our tilt angle guide explains why 15° to 25° facing south usually works best, and how the angle affects the height of the frame.

The legs are fixed either to concrete footings cast on the roof or with anchors drilled into the slab. Both work when done properly. Ask:

• How the legs are fixed, and how many there are
• How the roof is waterproofed where anchors go in, so it does not leak in the monsoon
• That the footings leave the roof’s drainage paths clear

Before the structure goes up

• Check the roof. Repair cracks and redo the waterproofing first if it is due. Lifting a finished array to fix a leak later costs far more.
• Plan the space. Agree where the water tank, the cables, the inverter and the walkway for cleaning will go.
• Agree the height in writing. “Extra structure height” is a common add-on after the contract is signed, so the quotation should state the height above the roof.

Our quotation checklist includes the structure lines to look for, and the types of structure we build are on our home page.

Common questions

How high should a raised solar structure be?

High enough to walk under comfortably at its lowest edge if you want to use the roof, and high enough to clear the shadows of parapets and water tanks. The exact height is set at the survey and should be written in the quotation, because a higher frame needs more steel and a stronger design.

Does a raised solar structure damage the roof?

Not if it is installed properly. The legs sit on concrete footings or are anchored into the slab, and every point where the roof is drilled must be sealed. Repair and waterproof the roof before installation, because it is much harder to do once the panels are up.

Is a solar canopy worth the extra cost?

Where you want shade over a terrace, porch or parking area, yes: the same structure gives you shade and power. If you only need the power, a raised frame costs less and keeps the roof usable.

Which is better for a solar structure, galvanised steel or aluminium?

Both are approved under PM Surya Ghar, along with ZAM-coated steel since May 2026. Hot-dip galvanised steel is stronger and is the usual choice for raised frames and canopies. Aluminium is lighter, does not rust and suits low frames, at a higher cost.