Websites for masons.

Scratch the mortar joint with a key or a screwdriver. If it crumbles to sand, or you can push a blade in more than a few millimetres, the joint is done. Other signs: mortar missing in chunks, brick faces flaking off, or damp inside the wall on the weather side. Left long enough, water gets behind the brick and you move from repointing to rebuilding.

That is most of the craft. We match colour, sand and joint profile, and on older houses we match the strength too — soft historic brick needs a lime-based mortar, and using hard modern mortar on it will crack the brick faces off within a few winters. Fresh mortar always looks brighter for the first season and settles in.

Efflorescence — salts carried to the surface as water moves through the masonry and evaporates. On new work it is normal and weathers off. On old work it means water is getting in somewhere, so we look for the cause: failed joints, a cracked cap, bad flashing or a downspout dumping against the wall. Sealing over it without fixing the water makes things worse.

Some of it, with hoarding, heated enclosures and additives — but it costs more and quality gets harder to hold. Mortar needs to stay above freezing while it cures. We schedule repointing and rebuilds for the season when they will actually last, and honestly tell you when waiting until spring is the better call.

Done properly, with joints raked to the right depth and a mortar matched to the brick, twenty-five years and often much more. Done badly — surface smeared over failing joints — you will see it fail in two or three winters. This is a trade where the difference between the cheap quote and the good one shows up entirely in year five.

If the mortar is failing but the brick is sound, repointing and a new crown may be enough. If the stack is leaning, the brick faces have spalled off, or the liner is broken, it comes down to the roofline and gets rebuilt. We take photos from the roof so you are looking at the same evidence we are before deciding.