Roofers in Bookhamworking from a yardon Eastwick Road

Plenty of Bookham's older tiled roofs are still on their original covering. Clay and concrete tiles can outlast the fixings holding them, so tiles start slipping in ones and twos without anything obvious having broken.

One slipped tile is a repair. A roof that sheds a tile every few weeks is telling you the fixings and battens have gone, and continuing to re-lay individual tiles is money spent on a roof that needs re-covering. Matt will tell you which of the two you have, even when the answer is the cheaper one.

The roads around the village and towards Bookham Common are well wooded. That is why the houses are pleasant to live in and why the gutters fill every autumn.

A blocked gutter does not simply overflow. Water backs up over the fascia line, soaks the board behind it and runs down the wall, so timber rot and damp patches appear at first-floor level long before anyone looks up at the gutter. Clearing is cheap; the rotten fascia and interior redecoration that follow are not.

Bookham houses have been extended repeatedly over the decades, and many of those extensions carry flat roofs laid a long time ago with barely enough fall to move water.

Ponding water sits over a joint or a lap, freezes, expands and finds its way in. We lift the old build-up, check the decking and firrings, correct the falls and re-cover, rather than adding another layer over a deck that is already soft.

Older Bookham properties often have tall stacks that have not been touched in decades. The mortar joints erode, the flaunching around the pots cracks, and water tracks down inside the stack rather than off it.

The symptom shows up as a damp patch on a chimney breast in an upstairs room, which is easy to mistake for condensation. Repointing, replacing spalled bricks, renewing the flaunching or fitting new pots deals with the cause.

Shaded slopes hold damp, and damp grows moss. Moss holds water against the tile surface, works into laps and breaks loose in heavy rain to block gutters and downpipes.

Stripping it back is straightforward work that extends the life of a covering considerably. It is also work best done carefully; aggressive pressure washing on an older tiled roof removes moss and the tile surface together.

A lot of leaks we are called to in the village were 'fixed' previously with a tube of mastic across a flashing or a valley. Sealant shrinks, cracks and lets water back in, usually within a couple of winters.

Correctly dressed lead does the job properly. Where a valley or an abutment has been patched, we take out the patch and replace the leadwork so the joint sheds water by design rather than by adhesive.