Rendering and render repairs in Hythe, Folkestone and Kent

Render usually fails slowly and in patches. Tap it lightly with a knuckle or the handle of a screwdriver: sound render rings solid, and render that has come away from the wall sounds hollow, which is called blown render.

Small cracks and the odd blown patch can be cut back to sound render and repaired, matched as closely as possible for texture. Colour is harder: a patch on painted render disappears when the wall is repainted, but a patch on old weathered or through coloured render will show.

When a large share of an elevation sounds hollow, patching becomes a false economy, because the sound render around each patch is usually the next to go. Stripping back to the wall and starting again costs more, but it is the repair that lasts, and it shows you the state of the wall underneath, which on an older house is worth knowing.

Re-rendering a large part of a wall can bring in the Building Regulations, because it can count as renovating the wall, which may mean improving its insulation at the same time. Building control will tell you whether your job does.

Older houses with solid brick or stone walls need to breathe. They were built to take in some moisture and dry out again, and a hard cement render stops the drying half of that. On those walls lime render is the right material: softer, more flexible and able to let the wall dry. A lot of damp in older houses traces back to cement render or cement pointing on a wall that was built with lime.

Modern cavity wall houses are a different case. Sand and cement render suits them, and thin coat silicone or through coloured renders are increasingly used because they shed water, stay cleaner and need no painting, and some are designed to go over external insulation. They cost more than traditional render and only perform when applied to the system's rules, so the choice comes down to the wall, the budget and how much upkeep you want.

Houses near the sea get more driven rain, more wind and salt in the air, and the elevations facing the south west take the worst of it. Render on those sides cracks and weathers faster, and any water that gets behind it has longer to do damage. A crack you might watch on a sheltered inland house is worth sealing promptly here.

The details matter as much as the render. Render should stop above the damp proof course, finished on a bell shaped bead that throws water clear of the wall, and never carry on down to the ground, where it draws moisture up past the damp course. Window sills need drips that throw water off rather than down the face, and every gutter above needs to work, because an overflowing gutter will stain and eventually blow the render beneath it.

Repairing existing render like for like needs no permission. Rendering a house that is currently brick changes its appearance, and depending on where the house is and what the render looks like, that can need planning permission. In a conservation area it does, and on a listed building it needs listed building consent.

Painted and rendered fronts are a large part of the character of Hythe's High Street and of Folkestone's older streets, so check with Folkestone and Hythe District Council before changing one.