Some useful pointing tips
Old joints should be raked back to at least 15-20mm, or deeper for paving, then brushed or washed thoroughly
to remove any dust. A power washer will often remove lime mortar from brickwork or dry mixed mortar from
patio joints.
For wall pointing, fill the bed joint first and then fill the perpendicular (upright) joints above it. This stops sagging.
After applying new mortar, leave the unfinished pointing to stiffen slightly, finish the joint by smoothing off with a trowel or pointing iron. Lightly brush over before the mortar has set hard.
Do not use old cement that has become ‘lumpy’. Avoid mixing too much mortar, especially in hot weather. Freshly mixed mortar is more effectively applied than that which has partly cured.
Different sands & mixes will flow differently, therefore it is important to find the right consistency.
Standard mix for wall pointing: 5 parts building sand, 1 part cement, add plasticiser to manufacturers instructions.
Use maximum amount when mixing by hand. Patio slabs or exposed brickwork, you may need a stronger mix.
For example - 3:1 sand / cement.
A good quality liquid plasticiser is required. Add this directly into the mix, not into the water.
For non structural applications, washing-up liquid could be used as a substitute for commercial plasticiser.
An approximate measure would be one third (1/3) of a teaspoon of concentrated liquid for 5 shovels
of sand and cement mix.
Bagged pre-mixed mortar may require a small amount of additional plasticiser, especially when mixing by hand.
Thorough mixing is still required as this will add air and make the mortar easier to use.
Lime Mortar (typically) 2.5 sand / 1 lime: Plasticiser is not required, but the mixing time should be longer.
The mix should be allowed to sit for a period after initial mixing, to allow it to self-bulk - then remix and use.