How To Install A Grp Roof Valley

In order to shingle this kind of roof valley a roofing professional has to install both roof faces at the same time which is quite slow.

How to install a grp roof valley. Dry fix valley trough installation video. The contraction of the grp in cold weather can tear the underlay apart at the laps in the valley trough units. Grp valleys have pre formed upstands to prevent the ingress of water and for mortar bedding some have integral sand strips to ensure a good adhesion between the mortar and valley lining. Soup to nuts riley shows the proper way of installing a valley on a roof.

Lay a strip of membrane down the valley 100 cm wide is ok. Lay two 7 wide feather edge boards down the valley with the thick edges butted together this is optional but provides strength to the valley should you wish to walk up it in the furture to make repairs etc. It is good practice to lay a width of underlay along the valley and then overlap the general underlay on each side of the valley over this. More information on tyvek roofing membranes http www c.

A roofing expert points out the important details for the valley when installing roofing membranes. It is therefore ideal if the underlay under the valley is not bituminous and is laid over the valley battens along with the main roof slope underlay.