Window U value regulations for replacements in 2026
Replacing windows in 2026? The legal limit is a maximum U-value, not a target. Here is what Part L asks of a replacement, where the new-build rules differ and when to go further.
Timber Patio Doors: Sizes, U-Values, What to Specify
Standard sizes, Part L U-value limits, hardware weight classes, thresholds and Part F ventilation: a manufacturer's guide to specifying a large glazed timber door properly.