Skip to main content

Valley Troughs and Joining Strips

Installation Advice

Valley Troughs

  • Valley boards must be installed to support the valley trough, this is a requirement of the NHBC standards
  • The valley bottom should be lined with a continuous strip of roofing felt to run the full length of the valley from eaves to ridge, the main roofing felt should then be lapped over into the valley bottom
  • Valley trough edges must be supported on counter battens and secured with galvanised clout nails at no more than 1m centres
  • It is important to ensure that the centre of the valley trough is pushed down firmly into the valley bottom before it is fixed
  • Tiles should be bedded onto mortar, which is laid on the sand impregnated strips which are factory bonded to the valley trough
  • Slates should be secured with clips or rivets in the usual way

Joining Strips

  • Strip back the roof covering over the party wall to provide room to work
  • Make good the roofing felt and battens over the party wall
  • Position the joining strip on top of the battens, directly over the party wall, and secure to the battens using galvanised clout nails through the outer flange of the joining strip
  • Make good the roof tiles or slates ensuring that they meet half way across the joining strip and are bedded onto a strip of mortar
  • nbs plus
  • riba

Web Design by Bluestorm