Winged Ant problem HELP

[SippingSipsmith]

Every year since been in this house I have this ant problem starting in May.

They come in via the sash windows but can't see any outside. It is on the side of house where we have a Virginia creeper plant on the house but like said I can't see ants on outside windowsill so not sure if the timing is related to when the Virginia creeper starts leafing or not.

Then when they come in they just die. No point me putting ant powder outside because reckon they're laying eggs in windows or they're in a brickwork cavity. No point laying down Nippon type poison/gel because they die before going back to any nest.

Any ideas? Really puzzling. Oh and they have wings so not sure what species they are?!

Had local pest man out recently for a mouse and he was useless so looking to do a bit of research on my own first. Thanks

You must have an ants nest somewhere, you just need to find it. Winged ants emerge as a group over a period of a few hours. Amazingly they will often synchronise their emerging with other nests in the area. After they have come out, the nest will continue until the next flying day. I find this quite fascinating, as it seems to depend on the weather conditions as to when they all decide to go. Here I can always tell if ants are flying because we get loads of seagulls flying silently (which is strange in itself) catching them in mid flight. The formic acid in the ants can have an alcoholic effect on birds, and can leave them literally drunk. We have a nest that somehow emerges inside every summer, in our study. We just use fly spray and open the windows, they are soon gone. If the nest is under concrete it is difficult to destroy it. They are harmless though, and soon go.