How To Install Tin Roof Valley

Use tape sealant between the valley trim and the panel.

How to install tin roof valley.

Steep slope roofs slope greater than 3 12 cut the panels at an angle for the valley then bend the hem end of the panel and hook it with a cleat. Place them directly onto purlins that are attached to the roof trusses beginning on the outside edge. These will stop the entry of rain wind and pests. Roof one side of the valley running the shingles across it.

With a clean valley you can lay down some peel and stick roofing membrane. Use 1 inch galvanized roofing nails. Install synthetic roofing underlayment or felt paper according to manufacturer specifications and then install the first piece of valley flashing. Shingle the other side of the valley the same way.

The washer under the screw head should seal to the surface of the panel without bulging or shifting. Fold the top over the roof ridge and cut the bottom along the drip edge metal. Then install a non corrosive metal valley flashing of 24 minimum width lap successive sheets of metal flashing a minimum of 12 inches and seal laps. Make sure that the end of the flashing panel is perfectly in line with the edge of the roof.

Lay one and two tab shingles as you near the valley so full size shingles will run across the valley. Install the roofing screws vertically along each rib in the panel. Snap a chalkline 2 to 3 inches past the valley center on the top layer of shingles. Close or seal off the ends with a wood or plastic strip under the panel at each end.

Lay the flashing down in the roof valley and start at the lower end of the roof. Place the first screw about 7 inches from the bottom and each subsequent screw about 18 to 24 inches apart along the vertical run. Stop nailing 6 inches from the center. Use fasteners to attach the panel to the structure making sure that there is complete compression of the sealant.

Install an underlayment centered in the roof valley. First clean the debris out of the valley including sawdust nails and whatever else is in there. Apply an approximately 3 inch width of asphalt roofing cement along the sides of flashing and embed shingles in mastic.