Kitchen extension ideas for UK homes in 2026: side-return, rear, wrap-around and kitchen-diner types compared, with layouts, glazing options, costs and planning rules. This guide is written by PG Property Repairs and Renovations, an FMB and TrustMark accredited building company based in Worthing, using real costs and timescales from projects completed across Worthing, Lancing, Shoreham, Brighton and the wider West Sussex area.