Solar Panel Roof Load Calculator
Solar Panel Roof Load Calculator — quick estimate
Before anyone lifts a panel, the structural question: how much dead load will the array add, and can the roof take it? Estimate the kg/m² and total tonnage by mounting type — then have the structure actually checked.
Your roof & system
Working bands: metal-sheet rail-mount ~15 kg/m², elevated RCC frame ~20 kg/m², ballasted RCC ~30 kg/m² (ballast included), over ~9.3 m²/kWp of array area.
Ask for an engineer's review of your roof for solar
Send your roof details; a structural engineer has to confirm adequacy, and the mounting structure is designed for IS 875 wind loads.
Have a BOQ, drawing or tender for this scope? Send it for an item-wise rate-analysis review →
Your request is in
Your request reached our team with exactly what the preview showed. If an engineer needs your drawings, bill or data, they will use the number you gave.
Indicative dead-load bands only — not a structural verdict. Wind uplift (IS 875), point loads at supports and your slab's actual condition govern; a structural adequacy assessment settles it.
Questions engineers and CFOs ask
How much weight does rooftop solar add to my roof?
As a working band: rail-mounted arrays on metal-sheet roofs add roughly 12–15 kg/m² of array area, elevated frames on RCC roofs around 18–22 kg/m², and ballasted RCC systems 25–35 kg/m² because the concrete ballast blocks that hold them down are most of the weight. These are dead loads spread over the array footprint — point loads at feet and pedestals matter separately.
Can my RCC roof take solar panels?
This calculator cannot say — it only estimates the dead load an array adds. Whether your slab can carry it is a structural engineer's decision: the slab's design, age, cracks, water tanks, existing services and cantilevers all matter, and a stamped structural adequacy certificate is what a lender or insurer will ask to see.
What about wind load — isn't that bigger than the weight?
Often, yes. Uplift on an elevated array in a storm can exceed its dead weight, which is why structures are designed to IS 875 wind maps for your location and why ballasted systems need enough mass to stay put. Weight is the question everyone asks; anchorage against uplift is the one the structural design actually sweats over.
Metal-sheet roof — will the panels damage the sheeting?
Not when the array clamps to the standing seams or fixes into the purlins through proper interfaces with EPDM sealing. What damages sheet roofs is walking traffic during careless installation and cleaning, and drilling that misses purlins. Specify walkways, purlin-fixed rails and a cleaning access plan and a sheet roof carries solar for decades.
Got your number — what next?
A calculator gives you a first figure. These take it further.
The work itself
Read before you specify
The terms behind it
Delivered work with this scope
- 120 kW Rooftop Solar for Bindal Agencies — Chennai— Bindal Agencies Pvt Ltd (Bindal Group)
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One of 56 free MEPF and solar calculators on this site. Every input term is defined in the engineering glossary; the specification libraries, clearance guides and checklists for design teams are in the architects' section.
Need an exact BOQ, rate analysis or measurement sheet?
This is a quick engineering estimate. For tendering, billing or audit, our QS & estimation team prepares an item-wise BOQ, rate analysis and a verified measurement sheet to IS / CPWD norms — backed by 15+ years of estimating our own projects.