Walls fail for various reasons: from poor foundations, neglect or exposure from the elements.
On period buildings a common problem is the decay of the faces in natural stone or brick. Natural stone such as sandstone and some period bricks, especially those which were handmade are made of much softer materials compared to their modern counterparts. This leaves them extremely vulnerable to the elements and unless properly cared for can increase erosion.
To resolve this problem we carefully rake out the joints in the wall by hand and point up using a lime mortar that is softer than the brick or stone used. The reason for this is that rain and frost will always attack the softest material, in this case the lime joints, whilst keeping but keeping the valuable stone or brick intact.
If a hard modern motor such as cement is used in replacement of a traditional lime mortar, this not only accelerates the problem but as natural movements in the walls occur, the strong rigid cement mortar will crack rather than flex allowing water to penetrate deeper into the wall and in some cases, show internally.
Any stone or bricks that are beyond repair are replaced with like for like, so that the appearance of the wall is seamless.
If your building is listed we can provide a lime analysis so you get an exact match of the original mortar.