Masonry/mortar bees?

[Jammy_Jim]

Hello there,

Would anyone know from past experience if the attached photo is masonry/mortar bee activity? And what should be done to remedy?

This is on our chimney and hoping we just need a solid repointing job and not taking the bricks out and a beekeeper!

Ta,
James

 

[jj4091]

I would say it depends if they have built a hive/honeycombe in the cavity. If they have and are still active you need to evict them first because that looks like a big area to be infested

 

[endecotp]

I would say it depends if they have built a hive/honeycombe in the cavity.

Mason bees are solitary bees; tney don’t create hives or honeycomb.

 

[Ivor Windybottom]

I'd be more worried about how weak the mortar is in general. Is it lime and sand? New or old?

They look like metric bricks, suggesting reasonably new?

 

[Jammy_Jim]

I'd be more worried about how weak the mortar is in general. Is it lime and sand? New or old?

They look like metric bricks, suggesting reasonably new?

Yeah it's wet and sandy, it'll be repointed as we've got the scaffolding up and bricky on the building already. However, we're trying to understand if we can just repoint with a stronger mortar to keep the bees out or it's a bigger job.

 

[Ivor Windybottom]

They look like burrows, they'd be very unusual weathering otherwise.

Whatever the cause, it must be too weak. But there's probably an internet full of lime mortar fanatics ready to say you have to let the building flex/breathe or something.

What's the age of the building? I'm wondering whether it's lime or just a builder who used one bag of cement to build the whole place. I've seen builders using what looked like wet sand before. Then I watched it all weather away.

 

[Jammy_Jim]

They look like burrows, they'd be very unusual weathering otherwise.

Whatever the cause, it must be too weak. But there's probably an internet full of lime mortar fanatics ready to say you have to let the building flex/breathe or something.

What's the age of the building? I'm wondering whether it's lime or just a builder who used one bag of cement to build the whole place. I've seen builders using what looked like wet sand before. Then I watched it all weather away.

It is Victorian, there has been some work to the chimney before but higher up. I think mortar looks so poor because soaked from behind and front. It's stood the test of time so far though it seems

 

[Ivor Windybottom]

Ah right, if it's old then it's excusable.

Cement works, but lime mortar has something of a cult following these days. I've pointed with cement over lime mortar, it looked great and didn't immediately explode. Many will tell you all the bricks will spall, but this doesn't seem to actually happen in the real world. Old bricks can crumble at any time, but if there's cement pointing then some immediately jump on this as the cause.

 

[opps]

That looks like a solid 9" wall. You have header bricks than run back to the internal skin. As far as I know, Victorians didn't build cavity walls.

 

[catlad]

Not guaranteed to be a solid wall as those headers might be tying the chimney breast in.

 

[Harry Bloomfield]

I would say it depends if they have built a hive/honeycombe in the cavity.

That is not a cavity wall, judging by the layout of the bricks, it is simply a double brick wall.

 

[jj4091]

That is not a cavity wall, judging by the layout of the bricks, it is simply a double brick wall.

Yes you could well be right after re-reading the post and noticing that it is a chimney and not a gable end as I first imagined.

 

[Ivor Windybottom]

Don't understand what the argument was - opps said it wasn't a cavity wall but I don't think anyone had said it was?

 

[Harry Bloomfield]

Don't understand what the argument was - opps said it wasn't a cavity wall but I don't think anyone had said it was?

I would say it depends if they have built a hive/honeycombe in the cavity.

 

[Ivor Windybottom]

Thanks, missed that. There won't be a hive anyway, I think we've established that. If they were the hive-making sort they'd only need one entrance, these look like individual pods for solitary bees of some sort.

If indeed they are, but they'd be freakish weathering. Either way, it's too weak to stop whatever made the holes.