Correct mix for repointing property (brick with lime mortar)?

You are better buying it pre mixed from some of the companies on the net that sell it, just type in lime mortar. This will give you a consistent mix. you need N.H.L ; lime putty : sand aggregates. It is not hydrated lime, which can be purchased from most builder/diy merchants and requires cement to set, AND DOES NOT MAKE LIME MORTAR You want 3.5 NATURAL HYDRAULIC LIME MORTAR. It is the wrong time of year to put it in, the temperature must remain above 5 degrees within the first 72hrs or it will become ineffective. There is no cement in lime mortar, this makes it ineffective as it takes over the properties of cement and does not allow your walls to breathe. Also try to stay off the brickwork as it is very difficult to remove, seen a few houses ruined by bad pointing. Expect to pay a lot more for a bag of lime mortar as opposed to cement. would not be using plasters sand as suggested by r Hughes as it is unwashed and only a 50/50 mix of soft & sharp. it must also be stippled to ensure it is compressed completely into the joints, as stated it is the wrong time of the year to start this task as the temperature will not remain above 5 degrees during the first 72 hrs, it will in fact take till march to go off fully Should you wish any further information just ask. Good luck Alex

Hi. You will need to buy some NHL 3.5 and a fine aggregate such as washed building sand or plasterers sand. You could also buy sharp sand and sieve it to the required size aggregate if you wanted. I would be doing a 1:2, lime:sand ratio as your house will be exposed to the elements quite severely. You also need to remember that sand bulks, so to get a true gauge you will need to do a bulking test on the sand and remember to tap the gauging utensil down to compact it, but not compress it with your hands! It's not a simple task to be honest, if it's done properly and it should definitely not be done unless the temperature is 5 and rising and will be staying above that temperature for the foreseeable future. Lime used during this time of year can take until mid-January to form a degree of frost resistance and not 72 hours as ADR have stated. I would be waiting until Spring to be doing this work. Also, you need to consider the joint profile which during this period could have been struck and cut, struck and ruled or overhand struck amongst others. I would go with either of the first two but an amateur or even average bricklayer wouldn't do it justice, this kind of work is best done by craftsmen with the right training and knowledge. Cement is a definite no-no, so steer clear at all costs. Good luck. Rick

either buy pre mixed bags, this can be a bit expensive but is very easy and you'll have a consistent colour though out. alternativley i would use a 5;1;1 mix sand cement and lime witch gives a nice yellow/white colour when dried