This lovely old stone farmhouse near Oxford had been re-pointed some years ago using a mix of cement and lime. This is a popular technique to enable the cement to blend in better with older properties, but whilst adding lime to cement may give it a more authentic look, unfortunately it doesn’t make it any more breathable.
If moisture is forced to escape through the stonework rather than through the mortar, eventually the stones will crack or their faces will come off. In this house, unfortunately this had already started to happen. Its lintels had also rotted due to damp having to escape via the stone and wood.
To solve the problems, we had to support the structure to prevent collapse, add new lintels and replace all the damaged stonework. To finish, we removed the lime-cement mortar mix and re-pointed with traditional fully breathable lime mortar.