How are Grand National fences constructed?

How are Grand National fences constructed? With the exception of the Water Jump, the fences on the Grand National Course at Aintree range in height from 4’6″ to 5’2″. Outwardly, they appear much the same as they always have but, following a research and development programme by the Aintree Racecourse Executive and the British Horseracing Authority (BHA), their anatomy has changed significantly in recent years.

Traditionally, Grand National fences consisted of a rigid timber frame which, although protected by foam rubber padding on the take-off side, was nonetheless solid. The timber frame, in turn, was stuffed with natural birch switches, cut and bundled together, and the fence was dressed with a loose topping of Norway or Sitka Spruce to a minimum depth of 14″. The spruce topping was, and is, intended to be forgiving, such that horses can brush through it, if need be.

However, striking a rigid timber frame at racing speed can be hazardous to horse and rider so, in the interests of safety, wooden posts and natural birch have been replaced by more forgiving, plastic birch units in all the plain fences on the Grand National Course. Thus, even if horses knock the spruce off the fence, they run less risk of becoming unbalanced and/or injuring themselves. Each fence is fronted by a foam padded rail, approximately one-third of the way up the fence, and a toe board, 14″ high, at the base to provide a clear sighting.