Skylight and rooflight guides

Each guide takes one rooflight question and works through it properly, from how a centre-pivot window turns for cleaning to what a lantern kerb is for. They are written for homeowners, so the trade terms are explained as they come up, and none of them is a sales pitch for one maker.

The guides sit under the product they belong to. For lanterns, they cover sizing and kerbs and adding one to a roof that is already there. For flat roofs, how upstands, falls and coverings work and how to choose a unit. Roof window guides compare the ways a sash opens and look at loft conversions; the VELUX ones deal with like-for-like replacement and with blinds and controls room by room. Others cover electric and solar opening, makers' rain sensors, U-values and solar-control glass, why glass mists between the panes, walk-on glass and its load ratings, conservation units on older and listed houses, and which rooms suit a sun tunnel.

Two guides apply to every product. The planning guide explains when a skylight on a house in England needs no planning application and when it does, and the Building Regulations guide covers approval, energy figures and escape. For daily use across every type, read our product-by-product page on daily use. If you want a quick reply rather than a long read, the answers index keeps each one short.

Reading a guide is a good way to arrive at the survey with the right questions, but it is no substitute for someone looking at your roof. When you have read enough, the booking page explains how the free visit works and what you get afterwards.