Does anyone know anything about bricks?

[greyvix]

We have a newish extension-5 years old. We bought hand made bricks to match the originals. I have noticed today that several are a raw colour and very powdery; they are near the base of the wall. It seems they are spalling (lost their protective surface), possibly due to frost damage. We obviously have had a very wet winter/ spring/ early summer.
Does anyone have experience of this? Is there a simple remedy? Please tell me the house isn't about to crumble!

Hi. Sorry to hear that you are having problems. Are they reds? Those often come up a bit soft especially in a strong cement mortar. Are they above or below dpc?

Different bricks have different weathering properties. Not all can be used in all situations. Also sometimes the bricks fired in the centre of the kiln dont get as much heat and are not quite as durable as the others.

You need to speak to the brickmakers and ask for the product sheet for your bricks. That will give a 2-letter durability rating which will tell you if the bricks you have used are suitable (ie above/below dpc).

Assuming that is all fine your house will not be crumbling but you may have a local issue with one or two bricks. In that instance you can cut out and replace the problem ones.

If you do find a bigger problem in that bricks have been used below dpc which are not sufficiently durable, you need to get back to your architect. They will then have to propose solutions and any costs should be covered.by their pi. If you just employed a technician or did a diy spec you will have to solve it yourself or maybe employ an rics surveyor to help.

Good luck and hope it turns out to be minor.

Thank you very much. They are below the dpc. We used an architect initially, but the detail was sorted out by the builder, who ordered the bricks on our behalf. I will try to contact the brick maker, if I can remember who we used. Unfortunately, the relationship with the builder ended up being tricky!

Fingers crossed the data sheet brings good news then!

greyvix mentioned spalling, which is the outer surface of the brick coming away in flakes like a shell, usually caused by a wet brick being frosted, especially if it is dense. Hand-made bricks are of less reliable quality than machine-made, and might be quite soft.

Efllorescence is just a powder of mineral salts, usually white, appearing on the surface of the bricks as tiny crystals, sometimes looking a bit like white mould. Sometimes it will brush of and sometimes it is hard. Either way it will stop appearing once the brickwork is dry, and will eventually weather away. Trying to wash it off with water makes it worse

spalling below the dpc needs attention, efflorescence is trivial. Bricks below the DPC will never be truly dry, and winters will often be icy, so spalling will never stop.

There is a row of bricks below the dpc that is affected. It is not efflorescence, and it is brick dust coming off. It is dusty, rather than flaky though, and they have not started crumbling away (yet). The rest of the bricks are fine. They are red ones, as suspected.
I cannot remember the name of the company who sold us the bricks, which is annoying, as they will need to be matched if i have to replace them.
Thanks for your very knowledgeable (as always) responses.

if you have to replace them, it would be worth considering a more durable brick below the dpc. It is unlikely to be a perfect visual match, but if done in complete courses, can look quite sensible.

Thanks. Good idea.