We've just renovated our house and the electrician insisted that we had to have trickle extractors to meet building regs. They are basically just holes to the outside with a fan that blows cold air into the house constantly and that you can't turn off. They're even in the loo which doesn't even get condensation. I can hear conversations from the street outside now! The manufacturers instructions don't say how to turn it off and a plumber we had out had no idea. Does anyone know how you turn them off? The rooms are always cold because of them.