Repointing stone walls in Langton Matravers

Rubble limestone elevations. A stone wall is not a brick wall with different units in it. The bed joints are uneven, the perpends wander, and the mortar does more packing than a thin brick joint. So we do not rake to a set depth.

On a Langton Matravers wall we take out what is loose, crumbling or friable, follow the decay back to sound material, and fill in stages so deeper voids are not left hollow. All of it with hand tools: an angle grinder on limestone takes the arris off and leaves a sawn line down a wall that was never straight. Joints are damped down before filling.

The mix, and where the joint finishes. Purbeck limestone is hard and dense, and the Langton Matravers walls are solid rubble walls with no cavity, so the wall has to dry out through its joints. That means a breathable lime: an NHL or lime putty mortar gauged to the original sand, and BS EN 459 sets out which lime is which. The joint is kept a few millimetres back from the face, slightly recessed, so the aggregate shows and the stone reads as the surface of the wall. The weather struck and bucket handle profiles you see on brickwork have no business on a rubble elevation, and neither does a flush joint carried over the stone face.

Taking cement off stone. The usual trouble on the older walls in Langton Matravers is hard sand and cement pointing put on in the last fifty years. It is slow work with hand tools, because the cement grips the stone tightly and will bring a face away with it. Spalling gathers under sills and beside downpipes; where a face has gone we cut the stone back or replace it against a sample, then point the surround in the softer mix. A trial panel goes up first, judged on how it will look weathered.

Chimney stacks and brick dressings. The stacks in Langton Matravers are often fired brick above the roof line even where everything below is stone. A stack takes weather on four sides with nothing warming it, so its joints go first and penetrating damp turns up on a ceiling below. We repoint the stack, renew the flaunching around the pots and make good the junctions. A low stack on a single storey range sometimes comes off a tower; anything on a main ridge wants a scaffold and is priced as its own line.

Boundary and field walls. Plenty of the walls along the Langton Matravers lanes are built dry or nearly dry, with little more than earth and a lean lime between the stones. Pointing one solid in a modern mortar wrecks it: the wall loses the drainage it was built with. Where one is coming apart we bed and pin it back with a soft mix, or say it wants rebuilding rather than pointing.

Repointing is not priced by the square metre. The area tells you little until someone has looked into the joints.

Depth and method. Joints are raked back to sound mortar, by hand on soft stone and brick, because a grinder widens the joint and takes the arris off. That slow hand work makes up the bulk of the cost.

The mix. Lime lets a solid wall breathe. Cement holds water against the face, and frost then takes it off. Matching the colour on Purbeck stone means testing sands until a panel dries right.

Exposure. The seaward and south west faces weather deepest, and salt in the joints means raking further back before the new mortar will hold.

Access. A boundary wall needs no platform at all. A gable or chimney needs scaffold that stays up while the lime cures, priced under the work at height rules.

Stone to replace. Where a Purbeck stone has spalled or split, it is cut out and a matching piece set in. Each one is counted in the quote, so you can see how many are allowed for.

Put these to another firm. How deep will they rake, and with what? Which mix, and has it been matched? How many damaged stones or bricks are allowed for, and is the scaffold included?

Walk Langton Matravers and you can pick out the walls pointed in cement since the war. The giveaway is a band of grey mortar standing proud of the stone, spread wide across the face to save cutting back into the joint. It is called strap or ribbon pointing, and on a Purbeck wall it harms both the look and the fabric at once.

The look is what the conservation area is concerned with. A stone wall should read as stone with mortar between it. Ribbon pointing inverts that, so the wall reads as mortar with stone showing through, and the shadow lines that give a rubble elevation its texture disappear. That is a change of appearance rather than a repair. The fabric suffers too: a hard cement band seals the one route water had out of a solid wall, so damp goes deeper and stays longer, and when the cement parts from the stone it takes a layer of face with it.

So ask any quote where the joint will finish relative to the face of the stone, and what happens to the existing cement. A quote that says nothing about either is a quote for a ribbon.

We are based in Boscombe, 11.2 miles away. We repoint in Langton Matravers and in Worth Matravers, Kingston, Acton and down into Swanage, broadly BH19, all of it Dorset Council territory. You would deal with Bournemouth Roofing & Building Ltd, registered in England and Wales, company number 15471719. Before you book a visit in Langton Matravers, you can read our customers' Google reviews, word for word, on our reviews page.

The firm is Thomas Hannen's, and he scratches out a joint and prices the job in person. We have a verified customer's 10 out of 10 on Checkatrade. Both the site visit and the written quote, broken into items, are free.

Most repairs in Langton Matravers need no application at all. What decides whether a change to the outside of your house does is who the council is, whether a conservation area or a listing applies, and whether the place sits in a protected landscape.