It doesn t matter where you start or stop.
Remove old roof or not.
Clean the roof with a push broom and remove or pound in any remaining fasteners.
What to do if the old roof is not straight if the existing roof has wavy horizontal lines you can take out the waves by snapping a horizontal line 1 2 inch below the shingle bottoms of one course.
If you re going to add a roof on top of an old one it s a good idea to remove any loose shingles and apply a new layer of 30 pound roofing felt before laying the new shingles.
By placing shingles on top of a damaged roof you ll affect the way the roof looks.
Be careful not to damage the flashing.
Your roof leaks when it rains if your roof is leaking it s usually better to get rid of the old roof so you can find the source of the problems and fix them.
More difficult to check deck when you tear off the old roof you get a look at what s underneath.
Once it s out of the way pull any nails and remove any shingles and underlayment that are underneath.
Besides being tripping hazards they can work through and damage the new shingles.
If you re keeping the old metal flashing carefully remove nails and bend it upward off the shingles with a pry bar.
Skylight and chimney flashings are often worth saving if they re in good condition.
When contemplating a new roof many people hope to simply do a shingle over and avoid the extra cost and mess of tearing off the existing roof and starting from scratch.
But if the current roof is curling this isn t possible.
Not only will the existing layer provide a secondary back up roof for the new shingles but it will also save the cost and inconvenience of removing and disposing or recycling the old shingles.
It s clearly easier and cheaper to leave the old shingles in place but there s some special prep work involved with a re roof removing vents ridge caps and misshapen shingles among other things and you still have to replace or add new flashing which sometimes can be tricky over old roofing.
Find a pre screened local roofing contractor.
For example if you live in an area that is subject to high winds keep in mind that shingles will hold better if fastened directly to the roof deck.
Work from the top bottom and sides to save back muscles.
You re better off removing the old roof.
Since it s being put on top of another less than perfect roof it s likely that it may not look as good as a brand new roof would.
In addition removing the old shingles will.
Install a course along the snapped line then install succeeding courses using a guide or a snapped line.
In fact the only pro to a shingle over is it s cheaper and cleaner.
Call for free estimates from roofing pros now.
Putting a new roof over a leaking roof won t remove the leaks.
