Repointing - lime or cement

[WasteOfPaint]

We recently bought a house and the survey report says a small amount of repointing is needed on one wall. Specifically, it says the gaps should be raked out to a certain depth and repointed with lime based mortar. However, the existing mortar is cement (1950s house). So if we followed the surveyor's instruction, this would be a small amount of lime mortar on top of the existing cement. Is this beneficial/a good idea?

Anyone?

If it was originally done with cement, then repoint it with the same .

Hello,
DH does this for a living and basically cement isn't breathable so any water that gets in cannot come back out. He recommends repointing in lime and spends a lot of his jobs removing cement and repairing the bricks/stone round where cement has been put in to then put lime in. Lime is much more breathable. Currently in the process of him doing our house but paying customers come first!

Thanks - this would only be minor repairs though. We can't afford to replace all the pointing, and anyway it's in good condition apart from this small section. So the question is if using lime is still beneficial in this scenario.

DH says the cement will trap the water regardless and lime on top of cement will make no difference.

It’s not beneficial if the rest of the house is already in cement. Where is the poor pointing? Can you post a pic?

He has said though eventually for the good of the house all the cement will need removing as it will cause problems later down the line.

Your surveyor is assuming that the original mortar is lime and has at some point been repointed with cement. He's telling you to rake back the mortar to remove the cement and expose the original lime. You can then repoint with lime on top of lime.

Putting lime on top of cement is a waste of time and money.

Hi I am ppops hubby I do this for a living.
The faulty mortar needs raking out to twice the width of the joint deep and replacing with lime mortar.

People charge per square meter for this work. The cost usually depends on the size of the brick work and the region you live in as people charge different amounts across the country. Maybe try putting the job on my builder and see what your local builders price it at.

Here is a pic from the survey report. The issues are only towards the top and on the front side of the house.

Thank you - I did get a quote already, but until I mentioned the lime mortar (based on the survey report) I think the guy was expecting to use cement, based on what was already there. That's why I started looking into it further.

That looks like stone rather than brick. Can you take a pic of a larger area?
In any case, if it’s only a small area, I’b be more concerned with matching the colour.
Up there it’s just movement from the roof and lintel. It will most likely crack again anyway.

@C4tastrophe Yes it's (fake) Bath stone.

I know this is a hard question, but @WasteOfPaint what approximately (even vaguely approximately) would it cost to redo a large 5 bed house from cement to lime pointing?

@Perennis where are you based? DH works it out by m2 and then calculates windows and doors and removes them. Depending on where in the country is the average m2 price. London is much higher then where we are.

Using cement instead of lime is the reason a lot of bricks spall and flake.

@PPop we're in Wakefield, West Yorkshire.

@Perennis there was a thread about it recently (the initial post was about a stone cottage but there is some more general discussion of repointing in the replies).

www.mumsnet.com/talk/property/4716358-re-pointing-stone-cottage-is-this-really-how-much-it-costs

Thanks! V helpful.

The house is stone not brick.

As @NotDavidTennant says, putting lime on top of cement is a waste of time (and money!). A breathable mortar is pointless if applied onto a non breathable one.

That makes sense of what the surveyor said, but I'm not sure the assumption is sound. I was under the impression that cement was typically used in 1950s builds?

If your pointing is good, you are likely to damage the bricks chopping it out.

1950s is quite late for lime mortar. Could you contact the surveyor and ask them why they think the mortar needs to be lime?

Very few 1950’s houses used lime , cement(and cavity’s ) had taken over by then .

sounds like your surveyor has seen the stone and jumped to conclusions.

I thought that cement reacted with water and damaged limestone. That might be why the surveyor recommended that it is replaced? Although if it is fake stone then I have no idea if it would be a problem?