How do I fill in drill holes in exterior brickwork?

Are you renovating your property exterior? Have you noticed drill holes in the mortar or even in the bricks themselves? If so, you’re probably wondering what's the best way to fill these holes. Let’s ask the experts for some professional advice.

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Are you renovating your property exterior? Have you noticed drill holes in the mortar or even in the bricks themselves? If so, you’re probably wondering what's the best way to fill these holes. Let’s ask the experts for some professional advice.

What is the best way to fill in drill holes in exterior mortar?

Filling in drill holes in exterior mortar is a relatively simple task. For an experienced DIYer, it should be easily achievable.

Use the following steps to achieve a uniform finish for your exterior mortar:

1. Cut out a 3-inch slot on every drill hole using a flat-angled chisel

2. Clean out any debris from the hole

3. Purchase some local building sand and cement

4. Mix some new mortar (to match the existing mortar you may need to try some test mixes)

5. Point in the mortar to create a smooth and level finish

Once the mortar has dried, it may take a few weeks until it becomes weathered enough to be completely unnoticeable.

What is the best way to fill in drill holes in exterior bricks?

Filling in drill holes in the face of exterior bricks requires a slightly different method to filling in mortar holes.

1. Dampen the area around the drill holes

2. Using a silicone gun, shoot some exterior-grade silicone caulk into the holes

3. Leave a few millimetres indent at the hole site

4. Grind up a matching brick to create brick dust (you can use a hammer or an angle grinder)

5. Mix the brick dust with cement at a ratio of 4:1 (dust:cement) with a small amount of water

6. Apply the paste to the hole to create a flush finish with the brick’s face

You should now have a completely uniform brick face once the paste has dried.

Should I always fill in exterior drill holes?

Before you fill in any exterior drill holes, it’s a good idea to investigate why the drill holes were made in the first place.

If the drill holes are there to allow proper ventilation or improve airflow, then filling them in may cause future problems with damp.

If you are planning any exterior home improvements, it’s always best to check with an expert before you begin.

To find Checkatrade approved exterior brick specialists working in your area simply enter your postcode into the box below.