Water Reed (Norfolk Reed) Thatching

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Water reed being collected and bundled ready for thatching.

Water reed is not grown specifically for thatching. It is an indigenous weed that is managed and cropped for thatching and some other purposes.Water reed is normally harvested after one year’s growth during late December through to late March. Continued cutting after this time results in cutting the tillers of the following year’s growth. The majority of cutters now use machines to harvest their reed. Most cutters try to cut and cart of the bed during these months. The reed then requires cleaning and sizing into bundles later in the year.For ease of handling most commercially grown reed is banded into large bales of 80-100. It is important that reed is tied, baled dry and kept dry.

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Exposed timbers prior to fire proof layer application and then re thatching.

Thatching onto rafters (water reed)

All old thatch requires removal, the roof timbers are assessed and quite often additional rafters are required as helper rafters. It is our policy not to remove any existing timbers. The roof requires re-battening with tanalised batten fixed with galvanised nails. Tilting fillets will be required on all verges.

We normally fit a breather membrane under the battens. This keeps the building dry instantly, eliminates dust and debris falling through into the loft area in the following years, which creates dirt and a fire hazard. The reed is fixed to the roof with galvanised steel spikes driven into the rafters holding a galvanised steel 8mm rod. Average centres of fixing up rafters are 600mm. Our normal thickness is 14” (350mm).

A block cut ridge is fitted to the apex to seal the reed. Work normally cut to an ornamental pattern, conservation officers do sometimes stipulate a straight cut. Our normal practice is to completely net all the roof with 19g netting. Abutments sealed with mortar or lead as preferred or stipulated.

Top coating/over coating (water reed)

This system is only suitable for certain roofs when a sound thin layer of reed exists. The new reed is either pegged to a sound base or spiked through existing reed work. All the specs are similar to above although it is normally around 12” (300mm) thick

The main advantages of this system are that it requires little disturbance to the roof. No timber works are involved. Only a limited amount of old thatch requires removal. A considerable cost saving can be achieved using this system.