When repointing theres a few basics to keep in mind to unsure that it will last after all your effort:
First you must rake out the old to a depth of at least 1/2 inch to be sure of a decent bed joint.Sometimes when existing pointing is perished you can remove it by simply using a wire brush & running it along the joint.Generally when raking out i will use a 4" bolster chisel rather than a plugging chisel,this has the obvious advantage of removing 4" of mortar with each strike of your lump hammer.
Once you have removed the old mortar wash down the area your about to repoint,theres 2 reasons for this,the first is to remove all the dust from the joints so your new pointing will be sitting on a solid joint & the second reason is to dampen the area before you point to stop your new mortar having all the water sucked out of it by the old brickwork causing it to crack & fall out.
Now to start the pointing.You will need to mix 4 parts sand to 1 part cement,any stronger on the cement will cause it to crack & will give you a green type colour in your joints.a top tip that ive used for many years is to add a small amount of pva to your mix(about 1/2 cap) .This will ensure good adhesion to the existing,stop it drying out to fast & make a waterproof barrier to your joints.
The style of your pointing is set by your existing pointing & theres a referance to the differant styles of pointing in the brickwork section
Mixing mortar
First you must rake out the old to a depth of at least 1/2 inch to be sure of a decent bed joint.Sometimes when existing pointing is perished you can remove it by simply using a wire brush & running it along the joint.Generally when raking out i will use a 4" bolster chisel rather than a plugging chisel,this has the obvious advantage of removing 4" of mortar with each strike of your lump hammer.
Once you have removed the old mortar wash down the area your about to repoint,theres 2 reasons for this,the first is to remove all the dust from the joints so your new pointing will be sitting on a solid joint & the second reason is to dampen the area before you point to stop your new mortar having all the water sucked out of it by the old brickwork causing it to crack & fall out.
Now to start the pointing.You will need to mix 4 parts sand to 1 part cement,any stronger on the cement will cause it to crack & will give you a green type colour in your joints.a top tip that ive used for many years is to add a small amount of pva to your mix(about 1/2 cap) .This will ensure good adhesion to the existing,stop it drying out to fast & make a waterproof barrier to your joints.
The style of your pointing is set by your existing pointing & theres a referance to the differant styles of pointing in the brickwork section
Mixing mortar
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