Another excellent article from our friends at Eurofit Direct on their blog Fit For Purpose.
Difficulty – Intermediate
Duration – a weekend (depending on the area you’re repointing)
However good the brick layer was; at some stage the mortar on your home or wall will begin to age. Which isn’t necessarily a bad thing, however at some stage the mortar will become recessed. The mortar will become softer due to weathering and you should look to repoint any areas of a wall or masonry building which is subject to this.
Mortar doesn’t actually hold the brickwork together but instead separates it. Gravity is in fact the element which holds any brickwork together. So if your mortar is becoming recessed it may be time to pick up a pointing trowel and refresh your brickworks stability and look.
Repointing brickwork is simple enough for an experienced brick layer; however for a novice or a ‘DIYer’ it can be a difficult job. I would advise anyone who is thinking about taking this project on to only do so if they have some brick laying/brickwork experience.
Now lets get down to business; today I will give an easy to follow guide on how to repoint brickwork. Starting with the tools and materials you will need.
Tools you will need:
- Bricklayers trowel
- Pointing trowel
- Bricklayers jointer
- Ladder/scaffolding if applicable
- Soft Brush
- Stiff Brush
- Mortar Board
- Cold chisel
Materials you will need:
- Hydrated Lime
Step 1 – Raking the joints of your brickwork out
I have seen many bricklayers and DIY enthusiasts rake brickwork out using an electric grinder; this is something I would not advise doing. I say this due to the fact that even the man with the steadiest of hands, taking the greatest of care will inevitably cause some damage that cannot be repaired on the brickwork.
Instead I would advise using your cold chisel. Take your cold chisel and hammer and carefully knock into your mortar; chisel to roughly 12mm in depth.
Important tip – When repointing part of a wall or building always work from the top down. I say this because you do not want to get any old mortar or dust blowing into your newly pointed brickwork.
Once you have got the joints to 12mm in depth take your stiff brush and completely clear all dust from inside and also from the face of the brick. Then using your hosepipe give the joints and brickwork a good soaking… You should do this to leave a facility of dampness in which your new mortar will be able to stick inside.
Step 2 – Deciding on the mortar mix
When repointing a wall or building, you need your new mortar to match the existing one. After all you could lose value on your home otherwise. Finding the right mortar to match can sometimes be a frustrating process, depending on the age of the old mortar.
You need to try and replicate the old mortars colour for obvious reasons but also its texture and strength. You will have to track down local sand pits in order to find the right mixture. When mixing different grades of sand with your cement keep consistency, the way to do this is using a measuring gauge. Do this by using a specific size container; remember to take note of your proportions.
I would advise using a cement-based pointing mortar of one part cement, one part lime and six parts of soft sand.However if you’re looking for an older looking mortar finish then you may want to use sharp sand with your hydrated lime.
Step 3 – Repointing your brickwork
When you’re mixing your mortar you need it to be reasonably stiff compared to the texture of mortar for laying bricks. Place your mortar on your mortar board and you are ready to begin repointing.
Take your bricklaying trowel and pick up a trowel full of mortar. Then using your pointing trowel cut the mortar into sausage shaped pieces. Pick up a short length of your mortar with the pointing trowel and push into your joint; remember to keep your bricklayers trowel beneath to catch any lose mortar. You should always point horizontal joints first.
Always push the mortar into vertical joints to begin with. When pushing your mortar into your brickwork joints make sure you do not smear the faces of your bricks. You need to allow your mortar to set before shaping it…
There are a few different joint finishes you can use on your brickwork; you could go for a struck joint finish, the way to do this is to sweep your trowel across and down the brickwork before brushing off with your soft brush. You can create a flush joint finish, which is the more common approach. To do this use your jointer and drag along the mortar, this will create a slight curve indentation. You should always do vertical joints first and when you have done a fair amount of your joints go back with your soft brush and sweep any loose debris/mortar away. Do this softly to ensure that you don’t pull any mortar out of the joints.