Free Tools
Structural tools, built by the engineers who sign the reports.
Screening tools for people working on commercial rooftop solar. All free, no sign-up, and all indicative. They exist to tell you quickly whether a roof is worth pursuing and what level of assessment it needs. None of them is a substitute for a signed structural appraisal, and we say so on every one.
Calculator
Solar panel roof load calculator
The dead load an array adds over its footprint, in kg/m² and kN/m², from module weight, module size, mounting type and ballast. Includes the typical ranges to check yours against.
Open the calculator →Screening Tool
Free structural pre-check
Two minutes of questions about your roof, and an indication of whether it is likely to need a desktop report, an on-site survey, or neither. Built around what our engineers ask first.
Run the pre-check →Form
Desktop roof survey form
The information an engineer needs to produce a desktop structural roof loading report. Fill it in once and the assessment can start without a round of questions.
Open the form →Checklist
Installer pre-brief checklist
What to capture on a site before committing to an array layout, so the structural question does not come back later as a variation.
Open the checklist →Decision Tree
Roof substrate decision tree
Work from the roof covering you are looking at to the mounting approach and the structural evidence that covering will require.
Open the decision tree →In Development
Wind and snow zone lookup
Site wind and snow context by postcode, so you can see early whether a location sits in a demanding exposure band before any calculation work starts.
Coming soonWhy these are free, and why they are honest about their limits
Most structural questions on a solar scheme get asked too late, usually once a layout has been priced and sold. By that point the answer is expensive whichever way it goes. These tools exist to move the question earlier, when it is still cheap to act on.
Every one of them is indicative screening only. They work from the information you type in, not from your building. They cannot see the purlin condition, the previous alterations, the plant already on the roof, or the exposure of your specific site. A calculator that claimed otherwise would be selling you a certainty it does not have, and we carry professional indemnity against exactly that kind of claim.
What they do reliably is tell you whether a roof is worth pursuing, and what level of assessment it warrants. When you need the answer signed, that is a Desktop Structural Roof Loading Report from £130, or an on-site structural survey from £600, both within the 48-hour delivery benchmark.
Screened it and need the signed answer? Engineer-certified, within 48 hours.