If you can’t afford to buy a bigger flat or house, what’s the next best option? To extend. If you live in a ground floor flat, then you can either go out into the garden, or down into the ground. Or both. Basement excavations are proving an incredibly popular way of gaining floorspace, but on some streets there are so many (and they are so large), that neighbours are growing increasingly concerned. On Canfield Gardens, there will be six basements in a row of nine houses if the latest one gets planning permission.

This will be the main topic of discussion at Tuesday night’s AGM of CRASH. CRASH is the slightly strange acronym chosen for the local residents association in South Hampstead – the conservation area between Belsize Road, Finchley Road, Broadhurst Gardens and West End Lane.

CRASH used to be moderately active up until a couple of years ago. Residents associations (bodies that the council formally recognises as representing a group of streets) often wax and wane depending on the enthusiasm and energy of their leadership. CRASH had very much waned.

Peter Symonds, chair of CRASH today, became involved when his then neigbhour – French rugby legend Thomas Castaignède – sought to excavate a basement. As a result, Symonds has since become something of an expert on basement excavations and their implications.

Aside from the impact they might have on water tables, building foundations, and the underlying geology of the area, basement excavations can also cause misery for neighbours both adjacent to and above the flat in question. Symonds points out that while the owner of the flat usually has to move out during the works, this is a cost they factor into the decision. Flats above don’t have any choice in the matter, and yet a basement excavation can go on for months, or even years.

The issue is a problem across this part of Camden. Crediton Hill Residents Association chair Larry Trachtenberg, recently suggested a moratorium on all such plans until more research into their impact had been conducted.

Frances Wheat, Camden’s head of Devleopment Control, will be speaking at CRASH’s AGM along with the relevant planing area team manager Bethany Arbery. The talk is entitled “Planning: What it’s all about and how you can get involved”, but expect the Q&A part to focus pretty heavily on that thorny basement issue.

Symonds has breathed new life into CRASH, but is very keen to get new members – not just for their £5 annual subscription, but so the group can be more representative. CRASH covers an unusually large area for a residents group, which means there are many issues besides basements that arise.

If you live in those streets and are even remotely interested in issues that affect the area, then why not sign up – it’s only a fiver! – and why not come along on Tuesday night to the Crossfield Centre on Fairhazel Gardens (roughly opposite The Arches wine bar) from 7pm. If you’re a property owner, then CRASH can help you navigate Camden planning and the conservation area restrictions, and if you’re a tenant, then you might find some good contacts for other problems such as parking, litter, overhanging foliage etc. etc.

You can read more about CRASH on its much improved website.