Pitched Roof Valley Gutter Detail

One of the areas of a pitched roof most prone to leakage if not constructed properly is the valley.

Pitched roof valley gutter detail.

Roof ridges and ridge tiles roof hips and hip tiles roof valleys roof verges and lead flashings. How to do a roof valley martin s roofing and guttering merton ltd for all your roofing needs. To get the most out of it is helpful to also read parts 1 and 2. Cut underlay to rake and dress over tilting fillets to lap onto metal valley.

The lowest course of tiles slates should not touch the roof membrane. Part 1 a guide to roof construction covers an overview of flat and pitched roofs. A common misconception is that the mortar bedding is there to prevent water access. It is an area where water is directed towards rather than away from therefore correct detailing and construction is essential.

Catchment area must be no more than 25 m gutter must be at least 250 mm wide. Cut tile and a half tiles neatly and fix to form a gap minimum 125mm wide centred on valley. Purpose made valley trough tiles should be supported by gutter boards where the roof uses single lap interlocking tiles they should be mechanically cut to the correct rake adjacent coverings should be neatly cut to form a smooth junction and preferably be cut from tile and a half tiles. Where a flat roof adjoins a pitched roof or where valleys or gutters occur the waterproof membrane should be carried up under the tiling to a height of 150mm above the flat roof valley or gutter and lapped by the roofing underlay.

Maximum catchment areas for valley gutters are given in table 8 of e2 as1 for minimum roof pitch and gutter widths. A valley gutter is where two main roofs meet or where there is a change in roof direction. The valley gutter problem areas can be made worse where there are surrounding trees and associated leaves and branches that can block the valley gutters up. Fold the top over the roof ridge and cut the bottom along the drip edge metal.

First clean the debris out of the valley including sawdust nails and whatever else is in there. Part 3 of the four part guide to roof construction covers pitched roof detail. Valley gutters are generally considered to be a problem area. With a clean valley you can lay down some peel and stick roofing membrane.

Ensure that valley boards plywood sheathing and tilting fillets provide full support for metal valley.