Heritage Stonemasonry

Your masonry matters to us…

The use of lime harlings or renders in Scotland have played a crucial part of preserving historic stone built structures which can be found all over Scotland, even in the town or down the street where you live. Harlings are basically applied to protect the house you live in.

The removal of OP cement based renders on a building that has been built in stone and lime mortar should be encouraged most definitely.

Not only will there be significant damage to the structure there will also be a degree of damage which will occur internally ie dampness on internal walls, cold stops, heat loss, unpleasant smells.

Ordinary portland cement doesn’t carry the correct properties for the use on rendering stone structures, lime renders do, breathability and flexibility are the two key facts when working on stone wall harlings.

Many people think by rendering their stone built home with a cement based render will make their problems vanish, not true.

It might look good and make you feel good after the jobs been done but in fact this process will have a massive detrimental effect on your home and to the integrity of the building not to mention the thermal lose which will also occur.

Lime mortar plays a crucial part of a traditional sand stone structure, apart from basically holding the structure together it plays a part together with the sandstone to release moisture back out into the atmosphere through the mortar beds, the moisture that is contained in the stone itself.

You must never use opc when re pointing or have it applied any where within the walls of a sandstone building this can cause decay to the stone and have some irreversible consequences which in turn would require surface repairs to the damaged stone.