
Tim Penny
Assuming you referencing 'period' as around Victorian. Using a cement based mortar for repointing lime jointed brickwork is not a great idea. An old wall that will naturally have a certain amount of moisture penetrating it then the joints are the only means of that moisture getting out. If cement is used it will cause future damp problems inside and out. The bricks will then stay moist, and as this freezes and thaws, the surface of the bricks will blow and deteriorate.