When the Special Duties Branch relocated to Coleshill in 1942, new Nissen huts were built to accommodate the men and provide space for them to work. Royal Signals personnel repaired and maintained the specialist wireless equipment. A chain was used to hold up branches so the huts could be concealed beneath the trees, hidden from enemy planes.
There are some surviving hut bases in Long Shrubbery Wood, the rest having been removed at the end of the war. The largest hut base is thought to have been the site of the workshop.