When to Replace a Thatched Roof

A new thatched roof installed by a Master Thatcher today will probably outlive him – and the owners of the house that the thatch sits atop.

Thatch is renowned for its longevity, which is one reason why this eco-friendly form of roof covering is still around centuries after tiles and slate took over as the more common form of roofing.

A thatched roof can last 50 to 60 years – but there’s a caveat: it needs to be well-maintained to keep looking good and functioning well for its maximum lifespan.

How to Prolong the Life of a Thatched Roof

Nothing lasts forever, and of course thatch – water reed, combed wheat or longstraw – is subject to natural degradation over time. You can, however, keep a weather eye on your roof, have a professional check it periodically and make any necessary repairs, also follow a few tips to keep it in good condition for as long as possible before it needs a total rethatch.

The most important part of the roof to keep in good repair is the ridge, which needs replacing every 10 to 15 years. The ridge is the thick block-like section of thatch (usually styled in a pattern) which extends along the apex of the roof. Because it bears the brunt of the wind and weather, it is the first part to deteriorate, and without the ridge to hold the rest of the roof in place, all the thatch is compromised.

Apart from keeping your roof ridge healthy, get the thatched roof cleaned at least once a year – professionals will remove leaves, moss, algae and dirt with special rakes. Keep trees and bushes growing near the thatch cut back, so the roof can dry out in the sun and wind as quickly as possible, avoiding rot and fungus growth. Avoid walking on the thatch which could cause damage, and take measures to deter birds and vermin which can damage the thatch.

Knowing when a Re-Thatch is Required

Despite your best efforts there will come a day when a total re-thatch is inevitable. Thatched roof replacement usually means stripping all the thatch covering off back to the roof timbers – and in some cases replacing even the timbers themselves.

A professional thatcher will know when the time for repairs, patching and re-coating has run out, and replacement is the only option. Some of the signs that the thatch needs replacing will be:

• The roof is shedding material
• There are visible dips in the roof surface
• There are leaks inside the building
• The flashings are damaged and peeling away
• Wire nettings, spars and fixings are visible
• There is a substantial moss and lichen growth on the roof

When it comes to re-thatching, a Master Thatcher will undoubtedly thatch the building in a style matching the original as closely as possible, using the same materials (usually the most durable water reed) and incorporating design features (such as ridge patterning) that are characteristic of the local area.

Qualified thatchers are craftsmen who take great pride in the traditional aspects of their trade, and you can rest assured that when it comes to replacing a thatched roof it will be well worth the investment.