The Lime Guys
Marés is the local term used in the Balearic Islands to refer to a sandstone. And unfortunatly over the years it has been combined with Cements in both the pointing, external renders and also covered with plastic paints which we will addres in another article.
A sandstone building usually tells you when the pointing is wrong. You see damp patches that never quite dry, stone faces starting to break away, or joints that look hard, cracked and out of place against the rest of the wall.
When it comes to lime/cal pointing vs cement: what’s best for your Mares building, the short answer is that lime/cal is usually the right choice for traditional sandstone – but the real answer depends on the age of the property, the condition of the stone, and what has been done to it in the past.
For most period Mares properties, the mortar should work with the stone rather than against it. That is where many problems start. Cement can look strong, but strength on its own is not what sandstone needs. It needs to breath and this is something that Cement does not allow, causing water to be traped.
Cement mortar is harder and less porous. On modern construction, that can be useful. On older sandstone, it often causes trouble. If moisture cannot escape through the joints, it may pass through the stone instead. Which is why we often see bubling walls on the inside of a building, also In colder weather, that can lead to surface spalling, where the face of the sandstone flakes or breaks away.
If you are having problems with an older mares property, Call us
