To install asphalt shingles start by installing underlayment and new flashing on the roof.
How to lay shingles on a roof.
Use the chalk line to snap a straight line vertically every 6 inches.
Do this on both sides of the roof.
Use your chalk and tape measure to mark about 12 inches up on the roof for the first set of shingles.
Once you ve done that cut your shingles to size if they re not already.
Repeat this on both sides of the roof.
Known in the trade as vertical racking or staggering this how to lay shingles method enables the roofer to install a single column of shingles all the way to the peak without the wasted back and forth motion necessary to fill several rows of stair steps.
Continue laying your shingles horizontally up the roof.
When installing shingles start by laying a narrow row of shingles at the bottom of the roof along the edge.
Mark 12 inches up on the roof for the first course of shingles then mark every 5 inches all the way up the roof to set your reveal.
Next lay the first full row of shingles so they re directly covering the starter row.
Then begin nailing the shingles to the roof working in rows and starting at the edge of the roof.