How To Install Roof Shingles Over Old Shingles

To level out an existing asphalt shingle roof rip down reduce the height of two courses of shingles as shown in the drawing below.

How to install roof shingles over old shingles.

Because asphalt shingles are routinely exposed 5 in rip down the first strip the starter course so that it is 5 in. Leave the old valley flashing in place and install new over it. The first row of shingles should overhang the drip edge of the roof. If the job is done correctly with the new layer of shingles laid flat over the existing shingles the old roof cushions the new one and serves as a secondary barrier should wind or water ever break through the new shingles.

Many roofers recommend using laminated or dimensional shingles for re roofs because they re thicker than. Damaged decking will need to be repaired before you can install any new shingles. Watch and see how easy it is. Shingling a shed and want some tips.

To lay out the design for the shingles begin at the bottom of the roof and place a tape measure inch from the edge of the roof to ensure the shingles overhang the drip edge. Handy home shows you universal shingling techniques that can be applied to any shed. Around an inch should do. All shingle manufacturers honor the warranty whether their products are used for a reroof or a new roof.

Rip cut the starter strip or starter pieces so that they butt up against the second course of existing shingles and are even with the front edge of the existing roofing. Attach with nails along the top edge of the strip. Each shingle will require around 4 nails underneath the tar line and about half an inch under where the next shingle will overlap. Step 3 cover the old shingles.

Use a starter strip or cut pieces for a starter course. Re roofers have tricks to lay new roof shingles over old so that the same step ups between courses are maintained but if any old shingles are cupped curled or otherwise misshapen those defects will telegraph through to the new layer. 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. Install a layer of roofing felt over the roof before you begin installing the new shingles.

Do this on both sides of the roof.