How to Repoint Brickwork — Step-by-Step UK Guide

What You'll Need

Before You Start

• Identify the brick type and age of the building. Pre-1919 buildings almost always need lime mortar. Using hard cement mortar on soft bricks causes irreversible damage.
• Match the new mortar colour and texture to existing sound mortar elsewhere on the building. Test a small area first and let it cure for a week — mortar colour changes significantly as it dries.
• Use our Repointing Calculator to estimate mortar quantities and our Mortar Calculator for mix ratios.
• Check the weather — avoid repointing in direct sun, rain, frost or strong wind. Ideal conditions are overcast and mild (5-25°C). Lime mortar is especially sensitive to weather.
• If the wall is listed or in a conservation area, check with your local conservation officer before starting. There may be specific mortar and technique requirements.

Step-by-Step Instructions

Step 1: Rake Out Old Mortar

Using a plugging chisel and lump hammer, or a battery-powered mortar rake, remove all loose and crumbling mortar to a depth of 15-20mm. Work carefully to avoid chipping the brick arrises (edges). Rake horizontal (bed) joints first, then vertical (perp) joints. For large areas, a mortar rake attachment on an angle grinder can speed up the work — but use with extreme care to avoid damaging bricks.

Step 2: Clean Out the Joints

Brush out all dust and loose material from the raked joints using a stiff brush. Then dampen the joints with a spray bottle or light hose spray. The bricks should be damp but not saturated — this prevents them from sucking moisture from the new mortar too quickly.

Step 3: Mix the Mortar

Mix the mortar to the correct ratio for your brick type. For modern bricks: 4:1 sand to cement with plasticiser. For older soft bricks: 1:1:6 or 1:2:9 cement:lime:sand, or pure NHL lime mortar at 1:2.5. The consistency should be firm — stiffer than bricklaying mortar. It should sit on the hawk without slumping.

Step 4: Fill the Joints

Load mortar onto the hawk. Using a narrow pointing trowel, press mortar firmly into the horizontal joints first, working in sections of about 1m. Push the mortar in layers — do not try to fill the full depth in one pass. Pack each layer firmly to avoid voids. Then fill the vertical joints.

Step 5: Shape the Joint Profile

Once the mortar is firm enough to hold a thumbprint (typically 30 minutes to 2 hours depending on conditions), shape the joint to the desired profile. For a flush joint, draw a flat trowel across the face. For a bucket-handle joint, run a rounded jointer along each joint. For a weather-struck joint, angle the trowel to slope the bed joint slightly. Match the profile to any existing sound pointing on the building.

Step 6: Brush Off Excess

Once the mortar has firmed up further (usually 3-4 hours), brush off all excess mortar and crumbs from the brick face using a soft brush. Use a stippling action — do not drag the brush along the fresh joints, as this will smear mortar onto the bricks.

Step 7: Cure the Mortar

For cement mortar: protect from rain for 24 hours and from frost for 48 hours. Cover with polythene if needed. For lime mortar: cure slowly by keeping damp with a spray mist and covering with damp hessian for 3-5 days. Lime mortar must not dry out too quickly or be exposed to direct sun during curing — it needs moisture to carbonate properly.

Step 8: Clean the Brickwork

After the mortar has cured (7 days for cement, 14 days for lime), clean any mortar stains from the brick face. Use clean water and a stiff brush. For stubborn stains on modern bricks, a dilute brick acid can be used — but never use acid on lime mortar or limestone/sandstone. Test on an inconspicuous area first.

Common Mistakes to Avoid

• Hard mortar on soft bricks: Using a strong cement mortar on pre-1919 soft bricks traps moisture and causes the brick faces to spall (blow off). Always use lime mortar on older buildings.
• Shallow raking: If you do not rake out to at least 15mm depth, the new mortar has insufficient depth to bond and will fall out within a few years.
• Ribbon pointing: Spreading mortar thinly over the brick face creates an ugly finish and traps water behind. The mortar should be flush with or slightly recessed from the brick face.
• Pointing in rain or frost: Rain washes out fresh mortar; frost destroys the bond. Check the forecast before starting.
• Not matching the existing mortar: Mismatched mortar colour, texture or joint profile ruins the appearance of the building. Always test a sample first.

Cost Estimate (2026 UK Prices)

Use our Repointing Calculator and Mortar Calculator for exact quantities for your project.