Replacing bricks in vaulted ceiling

[Web3]

We have a massive job ahead of us in refurbishing out basement (not to mention the rest of the house).

The basement has the same footprint as the ground and 1st floor, with vaulted brick ceilings. It's one of the aspects which attracted us to the property.

Some time ago a previous owner converted the basement by coating some of the walls with bitumen, spraying all with cement and then using foil backed plasterboard (clearly trapping a lot of moisture). This survived until we moved in, but the bricks have started to spall where the plasterboard meets the vaulted ceiling in some places. In time we plan on removing all the non-breathable material from the vertical sections of wall and replacing with lime plaster or another solution which will allow the whole wall to breathe and (hopefully) prevent further deterioration. We've started the ripping out, but it will take some time.

Where there is significant damage to the bricks, does anyone know if they can be replaced easily or if we would need to have some structural support in place prior to their replacement? I thought I would ask here for advice first before engaging with builders as we have found them to be very hit and miss with period properties.

 

[Stevers]

Those bricks should be wedge shaped (either rubbed to shape or made that way) so will be difficult to replace. It's hard to think of a sensible way that it could be done as those bricks would be the first ones installed when the arch was built. Might be better to remove the cement and bitumen to prevent further damage, brush the salts off and live with it.

Otherwise there are firms that do tuck pointing on Victorian houses in London. They have ways of refacing damaged bricks, and that might be an option. This is one of them (no connection) to give you some idea:
https://www.londonrepointingandrestorationltd.co.uk/

 

[Kearn]

Depends on the goal really… if they’re no longer structurally doing their job as the spalling is of a substantial depth, then replacement is probably the option. As mentioned it won’t be too say, as the bricks will be in more compression than a standard wall, so wiggling one out and popping another in doesn’t work. And then you have the shape of the brick. And the need for a tight packed bedding layer. Slate could help here…

the odd on or two being replaced is unlikely to require anything except common sense. You’ll still have the triangular load shift in play.

Chances are though, it’s just the outer skin that’s gone and the majority of the brick is still sound. And I’m assuming these were more consistent bricks than many where there’s crap in the middle reliant on the outer fireskin to hold them together.

The visual goal is important. Old bricks, especially once they’ve started deteriorating, will dust. A lot! Just because some have visibly spalled doesn’t mean the rest aren’t on their way, with moisture forcing its way out.

So, either a lime plaster, when you do the lower section, or at least a stabilising limewash will keep them in check. But they’ll no longer be visible red bricks.

Limewash maintains the aesthetic, as would a bag rub. A full plaster will fully hide the bricks tho…

 

[stuart45]

They can be built without any formwork.

 

[Cubist]

or if we would need to have some structural support in place prior to their replacement?

If it were me, and regardless of the unknown form of the individual bricks, I would not want to be underneath it if I were doing more than just lime washing or plastering.

Any brick vault structure has to be considered at high risk of catastrophic collapse when removing even just one or two bricks. Such jobs should never be conducted by amateurs.

Some here might suggest that others may like the idea of flattening a Cubist but the First Lady wouldn't be impressed - I hope.

 

[Web3]

Thank you to all the excellent replies.

Those bricks should be wedge shaped (either rubbed to shape or made that way) so will be difficult to replace.

It's clearly not going to be as easy as I had hoped! Though I suspected that it wouldn't be, I tried finding out information online about it, but couldn't find much outside of people replacing normal bricks.

Just because some have visibly spalled doesn’t mean the rest aren’t on their way, with moisture forcing its way out.

I've taken a closer look and there are definitely more bricks spalling, these are just the worst offenders (I think they've put some kind of sealant on the exposed bricks as well for good measure). We don't really want to cover them up or limewash them, but clearly if it comes to that it's better than them carrying on getting worse. I wish the builder who did the original work knew the effect that they were going to have.

They can be built without any formwork.

That's good to know.

Such jobs should never be conducted by amateurs.

I'm definitely planning on getting professionals in for this. We're hoping to avoid anyone getting flattened! I'm just trying to understand our options/what we are letting ourselves in for.

Does anyone have any company recommendations in the midlands/willing to travel which are capable of doing the work if we go down that route?

 

[Cubist]

Hopefully you will find a local team with some relevant experience. Come what may though it would be advisable that you check their references and demand a detailed schedule of works which MUST include a clear statement of methods and and equipment to be used to safeguard the structure from collapse. Also, it would be wise to check their insurance cover to determine who pays for what should the worst arise.

That's bad news regarding the sealant used by the former contractor as its most likely contributing to the spalling problem. I'm not at all sure there is any way to reverse any on-going effect but it may be worth some research on the topic.

 

[stuart45]

They can be built without formwork

That's good to know.

I've never seen it done in the UK like that. Mexicans do it with lighter, highly absorbent bricks and a wet lime rich mortar.
It might be difficult to find bricklayers experienced in this kind of work. I've worked on the construction of a few, but never replaced any bricks on one.
It's definitely doable if you know how. A mate of mine used to be a bricklayer for British Rail, so did quite a few jobs like this on the tunnels. Getting the mortar packed tightly into the joints is a key issue.
Stevers idea of repairs is worth considering. I built a small one in our kitchen, but because I had trouble getting the bricks in between the form and the lintel, when I took the form away a few of the bricks were twisted up a lot. Instead of cutting them out, I used coloured mortar to straighten them out a bit. It was supposed to be a bit rustic anyway.
under

 

[Cubist]

As I recall, Fred Dibnah demonstrated the techniques, some of them at least, in one of his tv shows 20-30 years ago. Many of these are still available on YouTube and worth a look.