Is Your Roof Suitable for Solar?

Three things determine whether, and how well, solar works on a given roof: how much genuinely shadow-free area you have, which way the roof faces, and whether the structure can safely carry the array. A site visit settles all three precisely, but you can get a realistic first read on your own roof in a few minutes, which is what this page walks through.

Roof type: what you're mounting on

The type of roof changes both cost and mounting approach, not just aesthetics:

• Flat RCC roof (the most common residential roof type in Gorakhpur). Simplest and generally cheapest to mount on, panels sit on a tilted frame bolted or ballasted to the slab, with clear walking space maintained around the array for maintenance and cleaning access.
• Sloped tin or asbestos sheet roof (common on some homes, and on many shops, sheds and small factories). Mounting uses rail systems that clamp to the existing roof structure. This works well but needs a roof in genuinely sound condition, an old, rusted or sagging tin roof is worth flagging before, not after, panels go up.
• Tiled/sloped residential roof. Less common locally but installable with the right mounting hardware designed for tiled surfaces, usually at somewhat higher labour cost than a flat RCC roof.

Orientation and tilt

In India's northern latitudes, including Gorakhpur, a south-facing roof section captures the most consistent sunlight through the day and is the preferred orientation where available. East-facing catches strong morning sun and tapers off by afternoon; west-facing is the reverse. Both are genuinely workable, typically at a modest output reduction compared to due south, not a dealbreaker. North-facing sections are the least favourable for panel placement and are usually avoided or minimised in the layout if better-oriented roof area exists elsewhere on the same property.

Tilt (the angle panels are propped up at) matters less than orientation for most rooftop installations, installers typically use a practical mounting angle suited to the specific roof and monsoon drainage, rather than chasing a theoretically perfect angle that would need seasonal adjustment. This is confirmed on-site, not something to calculate yourself.

Shading: the one factor that punches above its weight

This is the part most people underestimate. In a standard string inverter setup, panels are wired in series, meaning if even one panel in a string is significantly shaded, it doesn't just lose its own output, it can drag down the output of the entire string it's part of, similar to one weak link limiting a chain. A water tank shadow falling across a single panel for an hour a day can cost you more than that one panel's worth of generation.

To do a rough self-check before your site visit, walk your roof at a few different times of day (morning, midday, late afternoon) and note what casts a shadow across your intended panel area: a neighbouring building, an overhead water tank, a chimney, an antenna, or a large tree. A shadow that's only present for 20-30 minutes at one time of day is usually a minor concern; a section shaded for several hours matters a lot more.

None of this necessarily rules a roof out. Where shading is unavoidable on part of a roof, options include placing panels only on the clean portion, using micro-inverters or power optimisers so one shaded panel doesn't drag down its whole string, or in some cases an elevated mounting stand to clear a lower obstruction. Which of these makes sense for your roof specifically is exactly what a proper site assessment is for, see our how solar works guide for more on how string vs micro-inverter setups actually differ.

Structural load, in plain terms

A standard rooftop solar array, panels, mounting frame and cabling, is light relative to what an RCC roof is built to carry, so for the great majority of homes this isn't a limiting factor. It's still worth a look if your roof is older, shows visible cracks or water staining, or you're considering a larger system on a lighter-duty tin or asbestos sheet roof, cases like that get flagged during the site visit and, where warranted, a more detailed structural check is recommended before proceeding.

What we actually check on a free site visit

Beyond what you can eyeball yourself, our site visit measures usable shadow-free area precisely, confirms roof type and condition, checks your electrical panel and sanctioned load, and factors all of it into a system size recommendation, alongside your monthly bill (see our system sizing guide for how that combines with roof area to determine what actually fits).

Related reading

• How to Choose Your System Size
• How Rooftop Solar Actually Works
• Solar Sizing & Savings Calculator