What repair work asks of your tools
Repairing masonry is mostly about taking out what has failed and putting in something sound that matches what is around it. The most frequent job is repointing, also called tuckpointing: removing deteriorated mortar from the joints and refilling them. Other jobs include replacing a cracked or spalled brick, patching small areas and cleaning the surface.
Compared with building new work, repairs involve more removal, so the tools lean toward chisels, grinders and brushes. They also create more dust, which is the main safety issue and gets its own section below.
First, find out what you are repairing
Before choosing tools, look at the wall. Joints that are recessed, sandy or crumbling are candidates for repointing. A crack that runs through units or follows a stair-step pattern across the wall can signal movement in the structure, and fresh mortar will not cure the cause. In that case, a professional assessment is a sensible step. Bulging, leaning or loose sections also call for professional advice before any work begins.
Old mortar is often softer than modern mixes, and the replacement should generally not be harder than the original brick, or the brick can become the weak point and wear away instead. Matching the mortar type to the age and type of the masonry is a decision worth researching or asking about before you buy materials.
Removing old mortar
The goal is to remove the damaged mortar to a consistent depth, often described as roughly twice the joint width or a bit more, while leaving the edges of the brick undamaged. A sound depth is typically somewhere around half an inch to an inch, but the right depth depends on the wall and the material.
Hand tools
- Plugging chisel or cold chisel. A narrow chisel struck with a club hammer to break out mortar. It is slow but controlled, and it suits soft mortar and small areas.
- Joint raker or mortar rake. A hand tool with a hooked tip for scraping out loose material.
- Club hammer (lump hammer). A short, heavy hammer suited to striking chisels. Wear safety glasses, because chips fly.
- Oscillating tool with a carbide or diamond blade. Useful for narrow joints and tight places. A dust shroud attachment, if one is available for your model, helps.
Power tools
- Angle grinder with a diamond blade (tuckpointing blade). This is the faster route for long runs of joints. It is also the method that creates the most dust, and it can scar brick edges if you wander. Choose a blade that is narrower than the joint, work steadily, and use a dust shroud with a vacuum designed for fine dust where possible. Read the manual and our notes on using an angle grinder safely before starting.
- Hammer drill or rotary hammer with a chisel attachment. Sometimes used to remove larger areas or to take out a damaged brick, though it can be heavy to hold overhead. If you rent or buy one, learn about it first by reading about how to use a rotary hammer safely.
Mixed approaches are common: a grinder along the long horizontal joints, then a hand chisel to clean up corners and the short vertical joints where a grinder is awkward.
Cleaning out the joints
Once the old mortar is out, the joint must be clean. Loose crumbs and dust prevent the new mortar from bonding.
- A stiff brush and a narrow brush for the depths of the joint
- A vacuum fitted with a fine-dust filter, or a hose rinse if the wall and conditions allow it (check how water will drain and whether it could soak materials you wish to keep dry)
- Often, lightly dampening the joints before filling, so that the dry brick does not pull the water out of fresh mortar too quickly
Filling and finishing: pointing tools
- Pointing trowel. A small, pointed trowel used to press mortar into the joint.
- Hawk. A flat board used to hold a small amount of mortar at wall height. A small-scale alternative is a mortar board.
- Mortar gun or bag (pointing gun). Pushes mortar into deep, narrow joints in a neat line. Worth considering for repetitive work.
- Pointing iron or tuck pointer, and a jointer. To press the mortar in and then tool the joint to a profile that resembles the old work. Matching the profile helps the repair blend in. Tooling also compresses the surface so it sheds water.
- Brick brush. To remove the crumbs from the surface once the mortar has stiffened a little.
Fill in layers if the joint is deep, packing each layer firmly and allowing it to stiffen before the next. The weather has an effect: very hot, dry, windy or freezing conditions can harm the cure of fresh mortar, so follow the product’s guidance on temperature and protecting the work.
Replacing a damaged brick
For a single failed brick, you need to cut around it, break it out in pieces and clean the opening. The tools are those above, plus a brick set and club hammer, and a small trowel for bedding the new brick in mortar. Remove the old brick carefully so the neighbors stay intact. Larger areas of failed brick, or any suspicion that the problem is structural, merit a professional’s opinion.
Concrete repairs, such as patching cracks or chipped steps, use related tools like a wire brush, cold chisel and trowel, with bonding or patching products chosen per the label.
Dust protection comes first
Cutting and grinding old mortar and masonry can release fine dust that contains crystalline silica. Breathing it over time can harm the lungs, so this is a hazard worth taking seriously, especially on indoor jobs or long runs of joints.
- Respiratory protection. Use a respirator rated for fine dust, fitted properly to your face. A basic nuisance dust mask is generally not enough. Check the guidance in the tool and respirator manuals and in local rules.
- Dust control at the source. A shroud and vacuum on a grinder, wet methods where practical, and avoiding dry sweeping all reduce the dust you breathe.
- Eye and hearing protection. Safety glasses or goggles for chiseling and grinding, and earmuffs or plugs for grinders and hammer drills.
- Gloves and clothing. Cut-resistant or sturdy gloves, long sleeves, and boots. Fresh mortar is caustic, so use waterproof gloves when pointing.
- Work area. Cover or move anything you want to keep clean, keep other people and pets away, and wash work clothes separately.
- Ladders and heights. Work above your reach calls for a stable ladder or proper scaffolding, not a stretch from a step.
- Power. Use ground-fault protected outlets, keep cords out of the work path, and unplug a grinder or remove its battery before changing blades.
Repair can be a good DIY project when the damage is limited to surface mortar, but it is slow and physically demanding. Take frequent breaks, and consider hiring a professional for large or high areas. This is general information, not professional advice.