Providing structural roof calculations for solar panel installations for commercial clients

We have worked with several Motor dealerships and buildings on technology and science parks to establish what size of solar panel array is possible on a client’s roof. We have also been asked to look at photovoltaic array possibilities when designing new roofs for clients.

The majority of commercial buildings are repurposed as they are sold or rented so structural engineers are required to calculate what additional loads these existing roofs can take, as solar panels are a relatively new addition, and roofs were not expected to take loads above wind and snow.

How we work

We work directly with clients or with solar panel providers to assess and determine what additional load the roof can take. We will need to know whether you intend to have a ballasted system where the solar panels are on elevated frames or whether it will be a fixed system where panels are positively fixed into the underlying roof structure.

It is important that we know the type of system you need, the size and weights of the panels and fixings and your expectations for the size of the array. We take the time to complete the research on the likely wind and snow loads. Our calculations include all the solar equipment as well as full snow and wind loads so that your solar panels, roof and structure are protected.

Initially we will ask for any as built drawings for the structure to determine how the existing roof has been constructed. We will also complete a site visit to determine if there have ben any changes or modifications and what the reality of the existing roof structure is. We will complete this investigation with or without as-built drawings but with drawings it makes life a lot easier.

It is important to ensure that if you do not own the building, that you have the correct permissions from the landlord to add solar panels. Your solar panel installer will be able to give you a timescale as to when you will have seen a return on the capital investment in solar, but it will improve your environmental credentials as well as possibly make you some money if you can sell any surplus power back to the grid.