A new slate roof, finished right up to the chimney

The brief: a new slate roof that stays watertight

Slate is the roof people choose when they want a covering that lasts. A natural slate roof can serve a house for 75 to 100 years, so the brief on a job like this is simple to state and hard to do: every slate straight, every junction sealed, nothing left to fail.

This project is a new slate roof on a brick house with chimney stacks and a valley where two slopes meet. Those are the details that decide whether slate keeps its promise, and they are the details these photographs show.

What a slate roof asks of the roofer

Slate is laid in overlapping courses, each course covering the fixings of the one below, so the line of every row shows from the ground. Wander off true by a few millimetres at the eaves and the error grows all the way up the slope.

The slates are the easy part to see. The work that keeps water out sits at the junctions: the valley between two slopes, the ridge, and the lead that seals the slates against a brick chimney. Slate has no forgiveness at those points, which is why we give them the most time.

The work, slope by slope

The main photograph looks across the finished slopes to a brick chimney stack topped with terracotta pots. The courses run true across the slope, and the valley runs cleanly down to the gutter line beside the scaffold boards.

A close view shows the stack itself, where new slates meet the brickwork and stepped lead flashing follows the brick courses. Lead is dressed tight into the joints so water runs off the slate and over the lead instead of behind it. Another slope climbs to a second stack, with a roofer's shadow thrown across the slate: the scaffold gave us the same view the roofer had while working.

Each slope is checked against a string line as it goes on, and the lead is dressed last, once the slates around it are tight.

The finish on this new slate roof

A finished slate roof should look calm: even gauge, tight valleys, lead tucked neatly into the brickwork and a ridge that sits straight against the sky. Stand at the bottom of the garden and look up. If the lines are true there, they are true everywhere.

All work is backed with a 20 year written guarantee, and the paperwork is issued when the job is complete. The scaffold comes down on a roof we are happy to put our name to.

Thinking about slate for your house?

We quote slate against tile in plain figures, so you see what the extra life costs. Read more about slate roofing, our wider new roofs and re-roofs service and the lead work that finishes every chimney. Then ask for a free, no obligation quote. We promise to beat any written quote, and Hugh or one of the team calls you back to arrange the survey.