During the life of a thatch, various work will usually need to be carried out to ensure that the roof retains its aesthetic appearance, functionality and that the maximum reasonable lifespan of the roof as a whole can be achieved.

The main failure point of a thatched roof, by design, is the ridge. The purpose of a thatched ridge is to cover the exposed stems of the top ‘set’ of material. Without a ridge, the roof would quickly take in water and decay from the top down. Ridges are essentially a sacrificial component and need replacing every eight to ten years. Depending on the lifespan of the main roof, the ridge will be replaced two, three or four times before the whole roof needs renewing completely. Traditionally, Dorset cottages tend to have basic ‘flush’ ridges rather than the lavish patterned cappings seen in other regions.

At the same time as a new ridge, it’s common to brush down the main roof, removing any debris, leaves and loose material that are on the surface. The roof can then be ‘dressed’ to take out any irregularities and tighten the material into it’s fixings. Chimney fillets and wire netting will also be checked and renewed if necessary at this stage.

Moss may also be removed periodically, usually for aesthetic reasons. There are several conflicting opinions within the industry about whether to leave moss in situ or to remove it. Moss growth can cause excessive moisture to be retained by the thatch material, resulting in uneven, premature wear. However, there is also evidence that moss has antifungal properties which could possibly extend the lifespan of a thatched roof. Analysing each roof on a case by case basis is usually the best approach.

Occasionally, isolated repairs will be necessary due to factors such as isolated wear, severe weather conditions or animal inflicted damage. It’s usually possible to perform patch repairs to thatched roofs, extending their working lifespan considerably, although there is inevitably a point where this becomes economically unviable.