This is not unusual – it has to do with columns of air being disturbed by the renovation work – but that doesn’t mean you have to put up with it. Report it to your strata committee or strata manager (water pipes outside the lot are common property) and ask them to employ a plumber or a hydraulic engineer who really, really knows what they’re doing. Every plumber will tell you they can fix this – some can, many can’t.
By the way, there is evidence around that allowing water hammer to go unchecked can damage pipework and connections, leading to other much more serious issues.