Lime repointing - (Damp / Building Preservation)
We were called to inspect the interior of an external wall of a property. There were visual signs of dampness at the base of the walls internally in the sitting room and also a musty damp smell coming through the carpet. The edges were showing signs of moisture ingress through the dark staining.
Upon lifting the carpet we could see that the original brick floor, in some places, had risen and lifted.
Externally we noted the soil of the flowerbed was quite high in relation to the internal floor level abutting directly to the wall and that a well established climbing plant had spoiled the brickwork and mortar, to which also, some roots had migrated through the solid brickwork impairing the brick floor inside. Unfortunately and quite commonly we also identified a cement based mortar across the entire elevation and most extensively at the bottom of the wall, causing some bricks to spall.
This was a small job that demonstrates the need to understand the nature of how traditional construction dealt with damp.
We gently dug out some of the earth by 150mm deep and 200mm wide from the base of the wall which enabled us to repair the damaged brickwork where necessary due to the invasive roots from the plants. We were not creating any drainage as such because the property has cast iron rainwater goods, instead reducing the external ground levels very slightly to provide a small 'evaporation zone', for any moisture rising up in the solid masonry via capillary action, as there is no Damp Proof Course.
After taking varied samples of some of the existing and possibly original lime mortar, in order to gain a color match, we then used a pre-mixed lime putty mortar supplied locally by - Lime Stuff Ltd. - using their expertise and specially crafted traditional materials.