What I found behind this sandstone retaining wall changed the repair plans. Here are before and after shots. Various repairs had been done over the years including bricking part up and slapping cement mortar on it. It didn't look too bonny and was falling apart. Freestanding walls pointed with sand and cement behave differently to those pointed with lime. Cement repairs turn a homogenous black and the stone becomes invisible. This is clear where a gap in an old wall has been repaired. On original areas, even after more than a century, ferns might be growing in the mortar joints but the stone and lime maintain seperate identities and the stone is still stone coloured. On the repair however the stone and cement soon become indistinguishable. You can see this on garden and estate walls all over Western Scotland.
Taking this wall apart I discovered that it was originally built with lime. With the clients blessing, out went our plans to repoint with sand and cement and in came some restoration with a lime mortar. You can see the stones again and, being lime, you will still be able to see them in 150 years.
