Lime pointing tips....

[robbie77]

I have had "a go" at some lime pointing. The previous custodian of the house had at some point had sections of the house, outbuilding and outside walls re-pointed with a sand cement mix.
I suspect this is why some of my bricks have blown/ or the cement pointing is loose.

Also had some shrubs growing out from the bricks

old joints were scraped out

The lime did not go that well:
I used a 3:1 mix of sharp sand and nhl 3.5. I added lime and half sand in mixer then added rest of the sand. I mixed in cement mixer for about 15 /20 minutes and added a little water being careful not to get it too wet. I wonder if I did not get the mixture wet enough? I also tamped it with a brush after it had set for about an hour.
It went on very rough and the finish was quite bad ...

The joints are weather tight now at least but it is a much darker art than I thought would be. Do you think it needed more water. I did this yesterday.
Any ideas or tips to improve?

Cheers

 

[stuart45]

Did you mix it dry for 20 minutes and then add the water?

 

[robbie77]

I mixed it dry and added water at the end. It started to ball a bit so i added water until it was not balling any longer.

 

[stuart45]

You need water and then let it mix for 20 minutes. Not too much at the start. Then leave for 20 to fatten up and then mix for a few more mins adding water if needed.

 

[robbie77]

You need water and then let it mix for 20 minutes. Not too much at the start. Then leave for 20 to fatten up and then mix for a few more mins adding water if needed.

Ah so start with a little water in the mixer. Add lime and sand mix 20 mins etc?

 

[stuart45]

You can mix it dry for a couple of mins, but the mix needs water for about 20. It needs time to get air into the mix and become workable without having too much water in it. Let fatten up for another 20 and remix for a couple.
The wall needs to be wetted down first and the pointing needs to be kept moist and out of the sun for a week. Lime mortar won't carbonate properly if it dries too quickly.

 

[robbie77]

Yeah i hosed the wall down first. It won't et much sun that side of the house. Could i rake a bit out and put some over the top thats a bit smoother? Will it bond ok?

 

[stuart45]

You may be better to rake it out completely if you have any doubts about the first mix. Try and push in tightly, but don't hit it with the churn brush too soon. Normally the next day is better.

 

[Gerrydelasel]

Did you try again?