What are these small plastic inserts in brickwork? (I am now told they are weep holes

Avoriaz

My house was built in 2004.

There are a number of small plastic inserts in the brickwork. Some are above windows, one is above a ground level air brick and some are just apparantly randomly placed in the wall.

Are they drainage holes or some kind of ventilation?

I often see bees going in and out of them.

phill99

They are called 'weep holes'. It's to allow any condensation build up to drop down the cavity and then come out via these openings.

withabix

They are perp vents/weep vents and are dual purpose:

1) Discharge water from the top of cavity trays, lintels and DPCs
2) Ventilate and enable air movement within the cavity

They aren't always in a position where they would perform the first function.

Avoriaz

Thanks for that.

I have now read up on weep holes and learnt that modern plastic weep holes have nylon or plastic screens to prevent insects etc getting through.

I hope the bees enjoy sharing a small part of our house.

Last year we had a pair of House Martins nesting below our eaves. They raised two lots of four chicks but sadly haven't returned this year.