Repointing

The southern wall of our house had three steel I beams inserted into it and a big hole made, with an extension bolted on to the front. They didn't do anything with the face of the wall that was left behind (they were lazy and or skint) so as we're progressing with the house work my wife cold chiseled out old mortar (lime and cement), removed the overpaint, dirt and random crud (rawl plugs etc). She then repointed properly using traditional lime. It takes several days to dry and several weeks for the chemistry to work and reach full strength, but here it is pictured at least dry.

Lime is better than cement, in that it sets slowly so it's easy to work. It's naturally breathable and porous, it's softer than the stones and it self repairing. The downsides are that it's slow to set, so to construction does take longer, it's not a strong as cement and it eventually wears away.

Cement sets super fast, is super sticky & strong and it's pretty waterproof. The downsides are really that it's stronger and stiffer than the stones, so prone to cracking and damaging the stones. Because it's sticky and hard, it's difficult to get it out again. Unlike lime it's not self repairing, so once it' cracks you've no option but to hack it out and start all over again.

Suffice as to say you shouldn't use Portland cement with natural stone or soft bricks, but from the middle of the twentieth century until fairly recently most people did, and now we're faced with expensive bills to hack it all out and replace it with lime....!

Thankfully there wasn't too much cement used on this wall, so it wasn't too hard to get rid of most of it, and repoint with lime. Sadly the same can't be said for all the walls of the house or garden. Some have been really ruined with cement and getting it out is really expensive and slow work...

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