Windows & Doors Guide 2026

A complete 2026 guide to replacement windows and doors in the UK. Covers frame materials and how uPVC, aluminium and timber actually compare in use; glazing specification, U-values and the current Building Regulations requirements; hardware, security ratings and locking standards; how installation quality determines whether the specified performance is ever achieved; realistic 2026 costs by window type and property size; what a like-for-like quotation should itemise; and the questions to ask before you sign with any installer.