The cleats accommodate thermal movement in the valley flashing to prevent stress cracks.
Slate roof valley flashing.
As this weak spot on your roof directs large amounts of water it is a common source for leaks.
Then install a non corrosive metal valley flashing of 24 minimum width.
Brent ulisky of ulisky slate demonstrates flashing a closed valley at the 2015 slate roofing contractors association 10th anniversary conference near grove.
Use roof valley cleats at intervals of 24 o c.
For roof pitches of 6 or more per foot the flashing extends at least 9 under the roof covering on each side.
Structural issues inadequate construction improper roofing methods and material deterioration.
Roof valley flashing material options there is a lot of misinformation and confusion out there when it comes to properly waterproofing roof valleys.
For example in metal roofing systems valleys are commonly fabricated with hems but can also be fabricated without them in which case they could still be used for metal roofing or any other type of roofing.
Whether for slate shingle or metal roofing valley flashing adds detail and helps to direct water.
Valley flashing is used for flashing where roof valleys are constructed.
The first step to installing an open valley is to cleat your valley metal in.
Install an underlayment centered in the roof valley.
Apply an approximately 3 inch width of asphalt roofing cement along the sides of flashing and embed shingles in mastic.
A properly flashed roof valley should have an ice and water shield installed with roofing felt being properly secured over the ice and water.
The lower edge of the flashing should be held 1 2 short of the butt line of the slate tile or shingle in the succeeding course.
Common causes of roof valley leaks.
Lap successive sheets of metal flashing a minimum of 12 inches and seal laps.
Missing ice water shield.
Diagonal cuts can be made to the top corner of these slates in the valley so the pointy edge does not damage the metal.
Intersecting roofs using a closed valley must have the same slopes so that the shingle butts line up at the valley intersection.
Made with premium steel 28 gauge limited lifetime paint warranty easy to cut.
Next step is to install your starter course slate.
These items can be fabricated in many different profiles.
For roof pitches less then 6 per foot the flashing extends at least 12.