Stone-masonry and Pointing
We are happy to assist you with pointing work to traditional homes and walls. Weathering of sandstone can be unsightly; however RBS Builders can assist you with repair of existing sandstone stonework. We can perform all types of pointing work, from pointing steps or garden walls to larger scale projects like gable ends or repointing a complete house.
Mortar is a mixture of builder’s sand, hydrated lime and cement. It was invented to hold bricks together. When exposed over time to the wind, snow, rain and hot sun, this mortar will deteriorate and crumble, effectively keeping the bricks apart rather than together.
You can tell when it’s time for repointing brickwork by running a nail across the mortar. If it crumbles into a flow of fine grains, prepare for some pointing work.
Whether you are pointing brickwork or pointing a wall, you start the same way. Clean out the old mortar, preferably using a hammer and chisel rather than an angle grinder or disc cutter. Clear out the vertical joints first and then the horizontal ones. This sequence is necessary because if you start with the horizontal layers, you can risk damaging the brickwork.
Brush away all dust and other debris that may have accumulated within the joints before mortaring.
There are two types of mortar mixture: cement, hydrated lime and builder’s sand in the ratio 1:1:6 or sharp sand and hydrated lime in the proportions 3:1.
It’s important to choose the correct sand. The simple sand used for children’s play pits traps water in the mixture, sets very quickly and will only form a weak bond with the bricks.
When pointing a stone wall, make sure that the colour of the mortar is slightly lighter than that of the stone so it balances with the natural stone colour.
Weather is important when pointing brickwork. Do not attempt it when rain or frost are expected.
Start the job using a hawk for the mortar and a pointing trowel. Repoint the horizontal joints first, working the trowel in a downward direction and then sideways and keeping the trowel at a slight angle. Pull the mortar against the upper bricks by twisting your wrist. Repeat this process until the joint is filled.
The pointing can be finished off in a variety of ways. A flush finish with the bricks is the easiest. The hollow key finish is an inward curve than can be moulded with a tube or rod.
There is also a weathered finished that tilts from the top to the edge of the brick below.
The recessed key is a finish provided when the mortar is pressed back evenly from the top and lower edges of the bricks. It can look stylish with natural stone but is not a good idea for pointing brickwork in external locations, as water can collect inside and erode the recess.