Lime mortar is a magical thing, one part hydrated lime putty to three parts coarse sand is all you need to make this ‘old-fashioned’ version of cement. Add half a part of horse hair and it becomes base coat plaster, use water and lime putty and it becomes paint – whitewash. Put it in an airtight bucket and it’ll keep indefinitely as it only ‘goes off’ when exposed to the air.
This week we have mostly been re-pointing, this involves scraping out the mortar joints with a hoof-pick and then brushing down the wall and the joints ready to accept the mortar.
A lot of the joints in the bottom half of the wall appear to be mortared with mud – was the work of tree roots or rodents or a reaction to the rain coming in from the leaking roof? Strangely it was a work of fiction that answered this question rather than the old building reference books we had been looking for the answers in:
When their tender was accepted it was he who superintended the work and schemed how to scamp it, where possible, using mud where mortar was specified, mortar where there ought to have been cement…The Ragged Trousered Philanthropists – Robert Tressall
Sometimes re-pointing turns into re-building where we find stones loose or missing or, as in this case, whole sections of wall loose. what happened to the mortar? Did it wash out from years of rain or damp? Did someone else rake it all out years ago but never get around to re-pointing it?
It’s a long slow job, but it’s getting done.