Measuring a roof by drone: what you get out of it

Anyone planning a new covering, a solar system or a roof refurbishment needs one reliable figure first: how big is the area really? That is where the trouble starts. The building plans are often out of date because things were extended or rebuilt. And measuring it yourself means putting up a ladder, climbing onto the roof and reaching for the tape.

Why measuring from the ground is hard

A roof is sloped, often folded several times, and the interesting bits sit where you can barely reach. If you take the footprint of the house and multiply it by a factor, you can easily be several square metres out. With material that is paid for by the square metre, that is real money, in both directions.

How the flight works

I fly the building in a fixed pattern and take a great many images that overlap heavily. Every image carries the position it was taken from. From that stack the software then computes a true-to-scale model of the roof. If it has to be more precise, I first place measured markers on the ground.

For an ordinary detached house I am usually on site for a good half hour. You do not have to prepare anything, and nobody has to climb up.

What you receive

The imagery turns into a measurement with all partial areas, pitches, ridge and eaves lengths. Plus the details that tend to get forgotten in a quote: dormers, chimneys, roof windows, valleys. You get all of it as a PDF to print, or as a file you can carry on working with in CAD.

The full-resolution images come with it. They also show, as a by-product, what state the tiles are in, where moss has settled and whether anything has slipped.

Who benefits

Roofers and carpenters use it to price a job without putting up scaffolding first. Homeowners use it to compare several quotes on the same set of numbers. And with apartment blocks or halls it simply saves time, because an area that would otherwise take half a day is captured in one flight.