Anti Flood Airbrick Installation Guide

A step-by-step guide to installing the M3 FloodTec Anti Flood Airbrick

The worlds first Bsi Kitemark Certified Anti-Flood Airbrick!

These guideline steps are for retrofitting your airbrick. 

If you are installing these as you build your wall (new builds for example), see the tips at the end of this guide.

Step 1: Locate the position of your airbrick to be replaced.

Offer your Anti-Flood Airbrick in place, & gauge an approximation to whether it will fit in the new gap. 

Your new flood brick is designed to fit the traditional airbrick - yet on occasion, you may need to to carefully & neatly make more space (or plan for slightly more cement mix than usual to secure your new airbrick in place)

Using a concrete SDS pilot drill bit, & your hammer drill, drill holes through the mortar around the outside of your airbrick, taking care not to deface the surrounding bricks.

Bonus tip: You can also use a 4-inch diamond blade & your grinder to neatly chase the mortar also, providing a clean cut ready to be cemented later.

Please use the appropriate PPE for this!

Step 3: Using a hammer & bolster - or preferably your hammer drill & chisel bit, carefully remove the existing airbrick. 

Step 4: Make sure to remove all debris from the area and clean thoroughly.

Sand and cement does not bond very well to dusty areas, we therefore advise using a light mix of pva based water to clean the area - leave to go semi-dry.

Step 5: Offer your airbrick into the aperture to check it fits well, & the face of the Anti-Flood Airbrick is flush with the other brick faces.

If more space needs making, repeat previous steps.

Step 6: Before you complete your cementing, you need to open up your airbrick to complete 2 things. Firstly, use a hand held screw driver to remove the screw and face plate, placing carefully to the side (don't misplace your screw).

Remove the paper based instructions & information from within, checking if needed.

Next, check the mechanism is still clipped correctly in place. It is a push-fit in both corners inside the airbrick, allowing the closing plate to lift and drop.

To be sure, our team carefully removes the plate then re clips in. 

Refit your face plate & refix the screw.

Step 7: This stage is very important, please ready carefully.

Ready a mix of mortar for your airbrick, using sand, cement water & some pva or mortar plasticiser. Typically, your mix is 4 parts sand to 1 part cement, with the consistency being workable without sagging. You should pay attention to the colour and type of existing cement though, as many walls differ.

You can now cement in place your new Anti-Flood Airbrick. Double check your airbrick is facing the correct way (says front), and the spacers are at the bottom. 

You must achieve a full, even bed of mortar all the way round your airbrick, & all the way back to the rear lips. Water ingress will find the smallest gaps. Your airbrick face should be flush.

Take care to point the mortar to the best of your ability, avoiding spreading mortar onto the face of the surrounding bricks.

Step 8: Gently & carefully clean away mortar which may have spread onto the face of your airbrick.

Next, gently remove the film sticker to complete your installation. 

Other Tips:

Tip 1: You can stack up to 3 airbricks on top of each other where required, running along the same mortar lines. All previous steps apply. To assist them sitting correctly & flush, the top brick(s) can have the 8mm lip on the bottom rear edge removed with a hack saw.

Tip 2: You should perform maintenance checks on your airbrick annually, or after every flood event. This is done by removing the screw & cleaning out with warm soapy water (no harsh chemicals). Don't do this within 7 days of your airbrick being installed as the cement is still curing.

Tip 3: If you are not retrofitting your airbrick, & are instead installing it as you build your wall. You should make note of all previous steps with the exclusion of guidance on removing & cleaning the previous airbrick.