Avoid a costly replacement by shingling over old shingles.
However, you must take care toinstall shingles correctlyso they lie flat.
And a good job involvesinstalling new flashingsrather than relying on the existing ones.
Credit: Anthony Masterson Photography
Reroofing jobs are sometimes done without replacing flashings.
This provides added protection against ice dams.
Before you reshingle a roof, read our step-by-step guide for adding new shingles over old ones.
Credit: Dave Toht
Doing it now will make it easier to keep the reroofing job clean.
Use a flat pry bar or roofing shovel to pry out and remove the ridge shingles.
Remove all the nails.
Credit: Dave Toht
If you damage shingles while doing this, repair them (see next step).
If the broken piece is lost, cut a new piece to fit the existing shingle.
Install Flashing
At the eave and the rake, install U-shaped drip-edge flashing made for reroofing jobs.
Credit: Dave Toht
load the eave piece first, then the rake piece over it.
The two pieces should meet neatly at the corners.
Drive nails at high points on the underlying roof, the bottoms of the shingles.
Credit: Dave Toht
Attach it by driving nails into the outside edges only.
Do not drive nails less than 6 inches from the center of the flashing.
Install Starter Strip
Use a starter strip or cut pieces for a starter course.
Credit: Dave Toht
Attach with nails along the top edge of the strip.
Nail the shingles just above the tab slots.
Snap vertical control lines; there is no need to snap horizontal lines.
Credit: Dave Toht
Be sure the new tab slots do not align with the old ones.
Install Air Vents
Install air vents in a similar manner.
Work Around Walls
Where you meet a chimney or side wall, install step flashing.
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Install Counterflashing
Protect the step flashing with counterflashing.
On a chimney, use a grinder to cut an indentation into the mortar.
Apply mortar with a caulking gun and set the flashing into the mortar.
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Cut shingles into ridgecaps.
Snap lines on either side and implement the caps.
Cut Shingles
At the rake, snap a line directly above the edge of the existing shingles.
Credit: Dave Toht
Cut with a utility knife; you might want to use a straightedge.
Credit: Dave Toht
Credit: Dave Toht
Credit: Dave Toht
Credit: Dave Toht
Credit: Dave Toht
