Pointing Bricks and Stone

Often when you observe brickwork you will notice that the cement from between the bricks has started to fall out from the joints, this can happen on new brickwork but especially happens on old brick and stone work. The cement between the bricks is called “Pointing”.

Driving water penetrates the cement, the water is absorbed by the cement and when the temperature outside is low enough the water freezes making it expand, this then forces the cement from in between the joints, often leaving partial or full gaps between the bricks. Although this type of damage can be caused over decades, it is important to repair the damaged pointing as soon as possible as the brickwork will become even more porous and water will collect in the joints.

A critical step in the repointing operation is to identify wall areas that require repointing. Any sound pointing should be left undisturbed. Conditions that require repointing include: Mortar Erosion exceeding ¼ inch, Crumbling Mortar, Mortar with voids and hairline cracks in mortar. Visual observation in combination with light scraping can detect cracked, spalled and friable mortar joints. Repointing is a very labour intensive job, skills required for a successful job include:

• Cutting out the mortar joints to the proper depth and profile with minimal damage to the adjacent brick

• Proper preparation of mortar for repointing

• Proper placement of mortar by layering, compacting and tooling

• Accurate colour matching to adjacent, original mortar joints

Cleanliness of the repointing operation is also important, so that extensive cleaning of the finished wall is not necessary.

What will happen if I don’t repoint?

The exposed face of the mortar joint is subject to gradual erosion due to rain and wind. Frost attack also contributes to the breakdown of the materials. Once the exposed face of the mortar has receded behind the outer wall face, the Arises of the masonry become more vulnerable to erosion. At some point the joints become so worn that water can penetrate and saturate the wall. This then causes damp walls or damaged plasterwork and also the general look of the house exterior is reduced.

If left it can lead to very lengthy and costly job, Penetrating Damp and ultimately de value the property. Mortgage surveyors often qualify valuations and some times retentions can be made from mortgage awards until remedial action and repairs have been completed.

A lot of buildings are left to deteriorate to the stage where it becomes more economical and desirable to render the outside of the property. Pointing can be a very expensive time consuming operation and at the end of the day does nothing to help the deterioration or look of the brick surface. If it comes down to replacing brick faces as well as pointing then depending on the number to be replaced it becomes more economical to render.

Clear sealants and brick tinting can be used to restore the integrity of the brick surface the success of the job is determined by the choice of sealant and great skill and experience if it is to be tried by the DIY enthusiast we would reccommend starting somewhere on the building that cannot be seen easily in order to test colours, application practice and to develop the basic skills.