What you need to know before starting

Replacing roof shingles is a task you can do yourself if you have basic carpentry skills, a head for heights, and access to the right tools. The process involves removing damaged or worn shingles, inspecting the underlying roof deck for rot or damage, and nailing new shingles in place using the same fastening pattern as the originals. Most homeowners can replace a small section — a few shingles or one roof plane — in a day. A full roof replacement typically takes a professional crew two to three days.

Before you climb onto the roof, know that working at height carries real risk. Falls are the leading cause of serious home injuries. If you are uncomfortable on a ladder or roof, or if your roof pitch is steep (over 8:12), hire a professional. If you proceed, wear a safety harness, use a sturdy ladder, and work on a dry day with good footing.

Key Takeaways

  • You will need a pry bar, hammer, utility knife, measuring tape, and roofing nails; shingles come in bundles that cover about 33 square feet each.
  • Remove old shingles by lifting the tabs of the row above, then prying out nails and peeling away the damaged shingle.
  • Inspect the roof deck (plywood or OSB underneath) for soft spots, rot, or missing sections before laying new shingles.
  • New shingles nail down with four fasteners per shingle, placed in the nail line marked on the shingle itself, and should align with the rows above and below.
  • Asphalt shingles typically last 15 to 25 years depending on climate and maintenance; replacing a few shingles now can extend the life of the whole roof.

Gather tools and materials before you climb

You will need a pry bar (also called a flat bar or cat's paw) to lift shingle tabs and remove nails, a hammer for driving new nails, a utility knife to cut shingles to size, a measuring tape, and roofing nails (typically 1.25 inches long for asphalt shingles). Roofing nails have a larger head than standard nails and grip better in shingles.

Buy shingles that match your existing roof in color, style, and weight. Shingles come in bundles; each bundle covers roughly 33 square feet. For a small repair, one or two bundles are usually enough. If you cannot find an exact match and the repair is visible from the street, consider replacing a whole roof plane (one sloped section) so the new shingles blend visually. Bring a ladder, safety harness, and work gloves. If you are working in cold weather (below 50°F), shingles become brittle; warm them in the sun for a few hours first or wait for warmer conditions.

Remove the damaged shingles

Start by lifting the shingle tabs of the row directly above the damaged shingle. Shingle tabs are the flaps that hang down and cover the nails of the row below. Use your pry bar to gently lift each tab and break the seal — most shingles are glued down with a strip of adhesive. Once the seal is broken, you can see the nails holding that upper shingle in place.

Pry out the nails from the upper shingle carefully; you want to remove only the nails that hold it down, not damage the shingle itself (you will reuse it). Once the upper shingle is loose, move to the damaged shingle and pry out its four nails. Peel the damaged shingle away. If it is stuck, work slowly and use the pry bar to separate it from the roof deck without gouging the wood underneath.

Inspect the roof deck where the shingle was. Look for soft spots (press with your finger — it should feel solid), dark stains (sign of water damage), or missing sections. If the deck is damaged, that area must be repaired before new shingles go down. Small soft spots can be cut out and patched with plywood; large areas of rot require professional repair.

Install the new shingles

Lay the new shingle in place, aligning it with the shingles on either side. The shingle should sit flat and not buckle or wrinkle. Look at the shingle face — you will see a line of small dashes or a printed line marking where the nails go. This is the nail line. Position four nails along this line, one near each corner of the shingle. Drive each nail straight in; the head should sit flush with the shingle surface, not sunk into it.

Once the new shingle is nailed, press down on the adhesive strip along its bottom edge to seal it to the shingle below. If the shingle does not have a pre-glued strip, explore roofing cement (a thick, tar-like adhesive) under the tabs before pressing down. Now lift the upper shingle (the one you removed nails from earlier) and nail it back down, making sure its nails go through the nail line and do not hit the new shingle below.

If you are replacing multiple shingles in a row, work from bottom to top. This way, each new shingle is covered and protected by the row above it as you work upward.

Seal and finish the repair

After all new shingles are nailed and the upper row is re-nailed, explore a small dab of roofing cement under the tabs of the upper shingle to re-seal it. This prevents wind and water from lifting the tabs. Use a caulking gun or a putty knife to explore the cement; you need only a dime-sized amount per tab.

Walk the roof and check your work. Nails should be flush, shingles should lie flat without curling or buckling, and seams between shingles should be tight. If a nail is proud (sticking up), tap it flush. If a shingle is not sealing, add a small dab of cement under the tab.

When to call a professional instead

If the damage extends across multiple roof planes, if the roof deck is soft or rotted in large areas, or if you find missing flashing (metal strips that direct water away from valleys and edges), the repair is beyond a straightforward shingle replacement. Flashing leaks and deck rot require carpentry skills and specialized knowledge. Similarly, if your roof is steep, if you are uncomfortable working at height, or if weather is poor, a professional roofer can complete the work safely and with a warranty.

A professional inspection costs $100 to $300 and can identify problems you might miss — ice dam damage, improper ventilation, or underlying structural issues. If you are unsure whether your repair is a one-afternoon job or a larger project, a roofer's assessment is worth the cost.

Frequently Asked Questions

Can I put new shingles over old ones without removing them?

You can, but it is not recommended for a repair. Layering shingles adds weight, traps moisture, and makes future repairs harder. For a small fix, remove the old shingle and replace it. If your entire roof needs replacement, a professional can advise whether a second layer is structurally sound for your home.

What if I cannot find shingles that match my roof exactly?

Shingle colors fade over time, so new shingles will look slightly brighter than old ones for a few months. If the repair is in a visible spot and the mismatch bothers you, replace an entire roof plane or section so the new shingles form a visual block rather than a scattered patch. For repairs hidden by roof lines or trees, an exact match is less critical.

How long do replaced shingles last?

New asphalt shingles typically last 15 to 25 years, depending on climate, ventilation, and maintenance. Shingles in hot, sunny climates wear faster than those in cooler regions. If you are replacing shingles on a roof that is already 15 years old, the replaced shingles may outlast the surrounding originals — consider a full roof replacement instead.

Do I need to remove the nails from the upper shingle before I remove the damaged one?

Yes. The upper shingle's nails pass through its own body and into the damaged shingle below. You must remove those nails first so you can lift the upper shingle out of the way, then remove the damaged shingle. Once the new shingle is in place, re-nail the upper shingle.

What should I do if I find mold or rot under the shingles?

Stop and do not proceed with a straightforward shingle replacement. Mold and rot indicate a moisture problem — usually a leak, poor ventilation, or ice dam damage — that will destroy new shingles quickly. Have a roofer inspect the area to find the source of the water and repair the underlying issue before replacing shingles.