Timber headings are short lengths of hand excavated tunnels, used primarily where open cut methods or Trenchless Technology equipment is not an option due to the presence of services or because of access difficulties.
Headings are useful for short direct connections into existing manholes in built up areas, also under houses and other buildings where other means of access is restricted.
Instances when headings are appropriate for pipe repair or installation are, underneath highways and buildings where there is only a single access point or in built up areas where you cannot get access from above ground.
Headings can also be constructed to make connections of pipes and services underneath roads without having to excavate and cause disruption to traffic. Traditional timber headings are usually about 1.5m x 1.5m and up to 25 meters in length. Pipework is installed in the heading and the outer void is packed with concrete and grouted. The ground above is supported using timber frames constructed within the tunnel.
