Repointing advice

[plums]

Hi all

I have a property built in approximately 1910 using "Ruabon Red" brick which needs some areas of repointing.

Can anyone give me a clue as to what mortar needs to be used?

My understanding is that hydraulic lime mortar should be used to aid breathability as the property is solid wall construction but there seems to be plenty of people who say that Portland cement will do.

Thanks.

[Woody3]

What mortar is in place now?

Not too sure how soft "Ruabon Red" bricks are, but if it's a solid wall, I'd be using lime mortar.

The softness of the bricks will dictate what strength of NHL to use. Generally for pointing you use 3.5, unless the brick is very soft.

http://periodproperty.co.uk/forum/ is a very useful forum when it comes to old buildings.

[TimCrighton]

Hi,

This will depend on the 'hardness' of the bricks - basically the mortar needs to be softer than the bricks otherwise you are likely to suffer spalling.

Lime mortar was mainly used prior to the WW1, however Portland was actively in use also from around 1880 so it will also depend on what is currently in place. See if you can get a photo or get some examined locally.

If its Lime it should be replaced with Lime. There are some excellent places to get pre-mixed Lime Mortars and Plasters (and these stay workable for up to 4 weeks when sealed unlike portland mixes).

Lime is a great material to work with but its also not used by many builders so you will need to find a specialist probably or at least a builder that is prepared to use it and not default to Portland.

[FlossyThePig]

have a look at the SPAB website, loads of detail there.

There are plenty of specialists around and not as expensive as you may think. We had a lot of repointing done last year, including removal of cement based mortar to be replaced by lime based.

[plums]

Thanks for your input everyone, the link to the old houses forum was very useful too.