ASK THE EXPERT
Douglas Kent, technical and research director at the Society for the Protection of Ancient Buildings, answers your renovation queries
Q We have ‘tuck pointing’ on the old house we’re buying - can you explain what this is please?
Tuck pointing is a specialised way of filling joints in masonry, particularly brickwork, to give the impression that they’re finer and more regular than they really are. The joints are first filled flush with mortar coloured to match the bricks, then scored with a narrow groove into which a thin ribbon of contrasting mortar (normally white, but possibly black, red or brown) is inserted or ‘tucked’. It was often employed on façades or enrichments to emulate superior ‘gauged’ brickwork from the 17th to the early 20th century. Such pointing may be overlooked, especially if it has weathered, but remnants can survive in more sheltered areas; for example, below eaves or windowsills.
Q Do you have any tips on how to stop a window binding?
Where paint build-up or wrongly painted parts causes sticking, try an inorganic solvent stripper. If binding arises from a distorted frame, careful planing and sanding should help (though severe distortion may suggest structural problems, such as wall movement, which will need addressing). When sliding sashes stick, a general overhaul is often advisable. Avoid easing windows in damp weather or recently uninhabited buildings, because opening lights will free themselves when ambient conditions change.
Q Our fireplace smokes a lot, which I think is because the opening is too big for the flue. What do you suggest?
It is possible to reduce the openings of inglenooks and other fireplaces exceeding around 90cm2 by installing a register plate along with a smoke canopy or freestanding closed stove. You can also compensate for an oversized opening by raising the hearth. With a fireplace opening smaller than approximately 90cm2, a small canopy or tempered glass plate might be installed. A smoke canopy can also cure smokiness resulting from a fireplace throat that is too large or poorly shaped. If a chimney pot or cowl is restricting the flue, it should be refitted or replaced.