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Restoration & Refurbishment

Cement mortar repointing on victorian terrace???

We have contracted a builder to repoint the gable end of our end terrace. Having read on various sites about repointing that lime mortar should always be used on old brickwork which were originally build with lime, I was surprised when the builder said he was planning to use cement (4:1 sand cement mix).
Should I be worried about letting them go ahead?

6 Answers from MyBuilder Restoration & Refurb Specialists

Best Answer

Using a cement based mortar for repointing lime jointed brickwork is unbelievably stupid. This is an old wall that will naturally have a certain amount of moisture penetrating it and the lime joints are the only means of that water escaping. The joints are basically a sacrifial part of the wall and will allow any moisture in the wall to escape. If cement is used the water cannot get out through the joints and the whole wall will become damp both inside and outside. The bricks will then stay permenantly moist, and as the moisture in them freezes and thaws, the surface of the bricks will blow.

I do hope you have been straight with these people and dismissed them.

Richard Pillinger

2014-02-03T16:00:02+00:00

Answered 3rd Feb 2014

You should be extremely worried, there is no cement in lime mortar, lime mortar allows your house to breathe and stops dampness, cement will cause dampness. It makes no difference how much or how little cement you put in the mix, it takes on the properties of cement. Lime mortar is 3.5 or above natural hydraulic lime, with only sand and aggregates, no additives no cement and not hydrated lime which can be purchased from all builders merchants.
Is the wrong time of the year to be doing it as it cannot be used where the temperature drops below 5 deg in the first 72hrs, it takes 92 days to complete its cycle. It is a lot more expensive than sand & cement and harder to point up with. My suggestion is kick this builder into touch before he does serious damage to your property, and employ one who knows about older properties. Personally I've stopped all lime pointing jobs and am booking them for spring next year.
Should you require any further information feel free to ask.

Good luck Alex

2013-11-05T08:40:03+00:00

Answered 5th Nov 2013

Hi Ben.

Don't let these idiots anywhere near your house!!

A 1:4 mix is used in groundwork on modern builds and is in no way suitable for a Victorian house. You are very correct in that your house needs repointing with a lime mortar. It should be an NHL 3.5 on an exposed gable and maybe a 1:2 mix. The original finished profile would have most likely been 'overhand struck and cut' or 'weatherstruck and cut' and either would be suitable for your Victorian house.

Most modern builders have no idea regarding anything prior to the 60's and 70's and abuse heritage properties something chronic. Try and find a heritage specialist local to you who is trained in historic brickwork, it may cost you a little more but the job will be done properly!!!

I hope I have been of some help.

Kind regards,

Rick

2013-11-05T08:40:03+00:00

Answered 5th Nov 2013

Yes you should not go ahead with that it is wrong it should be a lime mortar mix that will let your brick breath and let any Moisture out and stop the bricks from blowing

2018-01-27T11:55:01+00:00

Answered 27th Jan 2018

On a Victorian property you should use lime

2018-02-05T12:20:02+00:00

Answered 5th Feb 2018

It’s good there are some good tradesmen out there I definately agree on the Lime Mortar do not use any water repellants remember bricks need to breath
Regards Chris

2018-02-26T17:35:01+00:00

Answered 26th Feb 2018

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