How a roof replacement works, step by step

A new roof is a big job, and knowing what to expect takes a lot of the stress out of it. Here is how a typical roof replacement runs, from the first phone call to the final walk-through.

Step 1: the inspection and quote

It starts with someone looking at the roof. A proper inspection covers:

• The condition of the existing roof and how it was built
• The roof area, pitch and shape (hips, valleys, skylights, vents)
• Access for materials and for removing the old roof
• Safety needs, such as scaffolding and edge protection
• What you want: colour, profile, insulation, gutters

You should then get a written quote that sets out the scope, the materials and the price, and the payment terms. Read it carefully and ask about anything that is not clear.

Step 2: choosing materials and colour

Once you are happy with the quote, you choose the details: the Colorbond colour, the profile (corrugated or square-rib), and whether to add an insulation blanket or new gutters. Seeing samples against the house in daylight helps.

Step 3: getting ready

Before work starts, the job is scheduled and materials are ordered. If any approvals or insurances apply to the job, they are arranged. You will be told when the crew is coming and what they need from you, for example keeping cars out of the driveway or moving things away from the walls of the house.

Step 4: safety setup

On the first day, the crew sets up safety equipment. Depending on the house, that can mean scaffolding, edge protection, harness points and a safe way on and off the roof. This comes first, before anything is removed.

Step 5: removing the old roof

The old roof comes off in sections, and the crew aims to open up only what can be closed again before the weather turns. Old tiles or sheets go into a skip or truck for removal. If the roof contains asbestos, it is a different process that must be done by licensed people.

Step 6: checking what is underneath

With the old roof off, the battens and frame can be properly checked. This is where problems hidden under the old roof are found, such as rotten or undersized battens. Anything that needs fixing is discussed with you before it is done.

Step 7: installing the new roof

Then the new roof goes on:

1. Sarking or an insulation blanket, if chosen
2. New Colorbond sheets, fixed to the battens
3. New valley iron where roof sections meet
4. New flashings around walls, chimneys, vents and skylights
5. New ridge and hip capping

Good flashing work is what keeps water out for the life of the roof, so it is worth taking the time to do it properly.

Step 8: gutters and finishing

If gutters, downpipes or fascia are part of the job, they are done now. The roof is checked from top to bottom.

Step 9: clean up and walk-through

The old roof is taken away, offcuts and screws are picked up, and the yard and driveway are cleaned. Then you are walked through the finished roof so you can see the work and ask questions.

How long does it take?

It depends on the size and shape of the roof, what is being removed, the access and the weather. A good contractor gives you a realistic timeframe in the quote and keeps you updated through the job.