Blue Tits nesting in box ?

Hi all.

I hung a nesting box on a concrete fence post last autumn but never really expected it to get used yet because its a bit exposed.
Anyway a few weeks ago a couple of blue tits started flying in and out. Then over the last few weeks they sort of stopped just going in now and again. Now the last few days they have started to go in and out all day again.
Went under the box earlier to do a bit of weeding and one of them in the tree didn't seam to happy so left that .
What do you thinks going on , nesting or just checking it out.
Was going to mow the lawn today but left that as well . .

 

Sounds to me as if they’re nesting in it.
If they’re both going in and out all day long they might even be feeding young.

 

Thanks do you think it's OK to carry on as normal in the garden ?

Been googling and blue tits feed their young up to a thousand caterpillars a day . That's a lot of caterpillars and a good reason not to spray I would say .

 

I wouldn’t go too close but otherwise carry on as usual … if they start shouting at you maybe move right away for a while.

We don’t spray here and have very little problem with caterpillars and aphids etc. the bluetits are always busy in this garden.