When we had some windows replaced about 7 years ago, they didn't come
with trickle vents (BTW, I don't mean night vent locking position
feature). We like this as it seems bizarre to buy new energy efficient
windows and then drill holes in them to let cold air in. A friend got
some around the same time (from Anglian) which did have them - I've no
idea if they were requested.

Anyway, we're due to get some more replaced soon, and I wondered what
the current position was regarding trickle vents. I'm aware they're
there to avoid damp, but the existing windows we have (old aluminium
double glazed windows without a thermal break) are airtight and we don't
have damp problems in rooms. The only problem we have with the windows
is they get covered in condensation because of the lack of thermal
break. This is one of the reasons we're replacing them.

So, do people see trickle vents as necessary, ideal, waste of time,
legally required? If we want some air in, we can open the window a little.

Thanks

David