Steel Beam Calculations for Building Control Approval. We design all Structural elements and advise or consult on the structural fundamentals of your extension or property development. We have over 30 years’ experience at www.onlinebeam.co.uk producing full Structural Design Packages from Surrey. We design steel beams or RSJ’s with full Structural Calculations for loft conversions, load bearing wall removal, extensions and commercial projects. We also design spliced connections and all other custom steel beam connections. We produce all calculations and fabrication drawings on CAD and IDEA design software. Our service is completely bespoke and our fees are very low with an online service for a national facility. We also design all concrete and brick-work structures, including foundations. We also design timber structures such as roof, flat roofs, floors, timber beams and purlins to flitch beams. Roof rafter calculations