Would you call my son excessively noisy?

We're living in a semi detached 'kit' house, the two houses are one building with a dividing wall between them. The floor boards upstairs are a bit loose and creaky (we can't make repairs, just to add, we're renting and our letting agent doesn't feel that repairing the floorboards is a priority because they're not a danger, no about to collapse and not so loose as to cause injury). I have two kids, a 3 yr old little boy and a 1 yr old little girl, and my son's favourite game is to pretend he's a racing car and run back and forth from bedroom to bedroom which let him do because it means I can get the tidying done and he's out of my hair for a. It's not a regular thing, it's just something he does when I'm upstairs, tidy's making beds, etc, but it is a bit noisy when he hits those creaky floor boards. The other day, while clearing out wardrobes and making space for winter clothes, which took me a couple of hours (the first time I've done this since we moved here 7mths ago), and my neighbour came in and, in a really rude and confrontational tone, demanded that my son be confined to the living room and not allowed to play upstairs from now on. OK if this noise was at an absurdly unsociable hour of the morning or night, but this was 4 in the afternoon, and he's got two kids of his own (although both are in their early 20's now) So my question is, do you think that a toddler running around in his own home on the odd occasion is an unacceptable amount of noise? Should I keep him confined in one room until the spring when the weather picks up just to keep my neighbour happy? What would you do in my situation?