Roof Installation: What to Expect

The process of roof installation typically includes planning and preparation, removing old roofing, making necessary repairs, installing underlayment materials, installing new materials and flashing, cleanup and inspection. Professional roof installation typically takes one to five days.

1. Prepare for your new roof

You’ll need to select a contractor, who will inspect your roof to determine exactly what’s needed to complete the job and then give you a written cost estimate for the new roof. You’ll also need to obtain any required permits (your contractor will likely handle this part) and arrange financing, if needed.

Once you’ve signed your proposal, your contractor will order all the necessary materials and have them delivered to your address. Your contractor will also probably have a dumpster delivered to your property a few days before the installation process begins, although some contractors may opt for a dump truck instead.

Clear the area around your house of anything that could get damaged while the contractors are working, such as outdoor furniture, planters, toys or sports equipment, and make sure your pets and children are out of the way.

2. Removal of your old roof

This involves prying up old shingles, flashing or other materials and putting them in the dumpster or truck. Expect this part of the process to be messy and noisy, with materials raining down from the roof, so you won’t want to go in or out of the house during this process unless absolutely necessary.

Your contractor might install the new roofing materials directly over the existing ones. This roofing method is called an overlay or reroofing, and it is generally cheaper, faster, more environmentally friendly and quieter. Opting for an overlay has some drawbacks, however, including the possibility of missed structural issues, possible compromising of certain roof components and the strain of additional weight on your roof.

3. Inspection and necessary structural repairs

Your roofer should take a careful look at your roof decking (your roofing support system). The contractor should repair or replace all rotted, broken or otherwise compromised wood, as well as pull up old nails. In addition, for a tighter, safer fit, the contractor should replace boards that have overly wide gaps.

4. Installing the underlayment

A roof underlayment is protective material that helps keep moisture out. After the metal drip edge is replaced, the contractor installs the underlayment on the roof deck and then covers it with special felt or tar paper for additional protection.

5. Installing the roof cover

The roofer will attach new roof materials, usually starting along the side edges and bottom of the roof deck. Asphalt shingles (if the roof is a shingled roof) go on next, installed in staggered rows; hip and ridge (capping) shingles finish off roof edges and hips. The activities in this part of the process can vary with the type of roof. For metal roofs, for example, the panels are screwed in rather than nailed. The contractor will also install new vents or replace your existing ones, as well as add flashing, which is a thin sheet of metal bent around joints to protect against moisture.

6. Cleanup and inspection

The contractors should blow debris off your roof, gutters and downspouts. On the ground, they should pack up tools, roll up tarps and pick up debris. Someone on the crew should walk around your entire property with a strong magnet to pick up any nails. The dumpsters or other large equipment should be removed from your property. Expect your contractor to do a careful walk-through inspection to make sure everything was done properly. If you had to get a permit from the city, you may need to schedule a formal inspection.