Structural Steels and Lintels: The Most Critical (and Complicated) Part of Your Extension
PremiumWhat structural steels do, who specifies them, how to verify your order, and why extension steelwork routinely exceeds initial quotes. Covers cantilevers, cavity width problems, and the ordering failures that delay builds by months.
Your extension walls are a dead weight without steels. Every opening you create, whether it's knocking through to the existing house, spanning across bifold doors, or supporting the ridge of your new roof, needs a steel beam to carry the load that the wall can no longer carry. Get the steelwork right and nobody ever thinks about it again. Get it wrong and you're looking at structural failure, building control refusal, or months of delays while fabricators redesign what should have been specified correctly the first time.
Steelwork is where the money goes, the arguments start, and the programme stalls. On real projects, the steel saga can stretch across 25 or more separate events spanning nearly a year: ordering failures, design changes, cavity width problems, unauthorised material substitutions, and multiple fabricator visits. That's not normal. But it's not unusual either.
Your structural engineer's calculations must be finalised before steels can be ordered. Walls must reach lintel height before lintels go in. Order steels as early as possible because fabrication takes 2-6 weeks, and delays here stall everything downstream: roof structure, windows and doors, and your building control inspection.
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