I spent three weeks at Theobalds Park cleaning it before it was dismantled.
Then when they'd rebuilt it they put a sheltercoat all over it.......stood out like a blind cobblers thumb
Still glad I'm not involved in the hash up they're making of cleaning the exterior of St Pauls adjacent to it :shock:
When you look at an elevation that's been cleaned it looks clean but when I look at the large areas of ashlar stonework all my eye can see is the gun shading from the cleaning.Professionally speaking, I'd say that they have used a small nozzle close up and cleaned it dry which has left marks on the stonework, suggesting an uneven clean. The cleaner has moved the nozzle up and down in a repetitive fashion so that it has left lines and when he's made the return at that point the stone has sufferred a deeper clean than other areas. So as the building resoils the gun shading will become more apparrent, giving it a more mottled appearrance. A bigger nozzle, further back with the introduction of water on the surface to soften the impact, would have produced a flatter more even and less intense clean and allowed the operative more dwell time to gradually reduce the soiling......
Well you did ask