Should Roof Valleys Be Pointed

Some homeowners prefer the consistent look that a woven valley provides.

Should roof valleys be pointed.

I had my roof retiled about 6 years ago. To change a valley on a tiled roof the ridge capping at the top of the valley has to be removed. I mark the shingle where the valley center crosses the top edge and i mark the roof at the top outside corner of the shingle. To achieve a woven valley installation a roofing professional lays shingles in the valley and weaves them together.

I had it repointed again in october 2014 and it has fallen out again from under the roof tiles. A scaffold tower has been used for access in this video. Roof valleys are troughs that discard runoff water where two sections of sloped roof meet. The upstands will prevent water ingress even if the mortar is missing or damaged.

Drip edge metal valley flashing dormer chimney and kickout flashing are types of roof flashing that shed water away from the connections between roofs walls chimneys and other building assemblies. Nrca lile points out that woven roof valleys are limited to cutout style 3 tab asphalt roof shingles as there are no openings to weave solid or architectural or dimensional or laminate style asphalt shingles together and he adds that the valley s slope should be at least 4 in 12 or steeper installed typically over a layer of mineral granule faced roll roofing. Then it has to be reinstated after the valley change. But if the shingles are not laid in the valley properly a woven valley may not lay flat creating bumps and detracting from the overall look of the roof.

To shingle out of the valley with laminated shingles lay a shingle down as a gauge and mark the corner at the bottom left and top right of the roof. Nevertheless they are often omitted from lead valleys. The valleys on many older houses comprise layers of roofing paper which can deteriorate over time. I had it repointed but it fell out again after another year.

After about a year the pointing from one of the valleys fell out. I suspect it has never been done properly each of the 3 times it has been pointed. The upstands or tilting fillets at each side of the valley are an important feature of good valley construction as they keep the water within the centre area of the valley. This video shows how to repoint a lead roof valley.

Valleys are typically found where gable dormer roofs meet the main roof or when a house has angled wings or additions where two roof sections in different planes meet.