Lay out chalk lines, then gently break the seal between shingles. This can be done with a “shingle ripper” or “slate bar” tool, which can also be used to remove any nails that prevent the flashing from going into position. The flashing’s bottom edge should never extend beyond the drip edge of the shingle. Before drilling, place the flashing in its correct position and mark the exact pre-drill point.
Once rafters are located and marked, and the post position is determined, drill a 7/32-inch pilot hole into the center of the rafter and fill with the roof manufacturer’s approved sealant. Be sure to drill the pilot hole 90° to the pitch of the roof. Pilot holes are used to prevent splitting the wood with your lag screw (or hanger bolt). The size of the pilot drill bit should be about 60% to 70% of the screw that is being installed. For example, if your lag size is 5/16, then your pilot drill bit should be about 7/32 or 1/4 inch.
Slide the flashing under the shingle to align with your chalk lines and pre-drilled pilot hole.
Drive the hanger bolt with its sealing washer into the rafter to the correct torque specifications listed by the manufacturer.
Cap off the block with an EPDM sealing washer to prevent standing water in the mounting block’s hole. EPDM is a high-heat-resistance rubber that works well with PV system mount components.
Attach the rack system to the mount and proceed with your PV installation! This picture shows a standard L-bracket that is fastened with a fender washer, a lock washer, and a nut. Most all-in-one flashing and mount products are designed to be compatible with standard PV racking systems. This example shows Quick Mount PV mounts with Iron Ridge rails.