Storm season starts in September — so August is the month

Roof maintenance has an awkward property: you notice it was needed once it is too late. The weather does hand you a schedule for it, and it is surprisingly precise.

Dutch meteorological institute KNMI notes that the storm season begins in September and that the first storm often arrives in November. That is your window: whatever is checked and repaired in August goes into the season intact. Whatever you leave until October has to be done in the period when every roofer is busy and the work itself is interrupted by the weather.

What tests a roof is not the mild days but the outliers. KNMI describes wind gusts as brief squalls or gusts of at least 50 kilometres per hour; from 75 kilometres per hour KNMI speaks of severe gusts, and gusts over 100 kilometres per hour are called very severe gusts. Such a gust finds the weak spot: a tile that no longer grips, a raised roof edge, a strip that has come loose at a detail.

In practice that means a short list before September: ridge and verge tiles for grip, roof edge and junctions for loose sections, and the roof surface for shifted tiles. Whatever you cannot judge from the ground, a roof inspection covers for € 150-350 with photographs. Loose tiles are then repair work at € 150-500 — in November that same tile is an emergency job with water damage underneath. Every guide rate is in the price index.