Building a basement? Make sure you don't dig yourself into a hole

Building a basement? Make sure you don't dig yourself into a hole

How to avoid a mega-basement blunder

The press is currently full of tales of woe about problems with botched basement digs.  Recently, a £3.5m Georgian townhouse in Barnes has collapsed “like a pack of cards” following work on a new super basement.

Another family in Chester Row are still waiting for at least £250,000 of repairs to the house three years after it was damaged by a neighbour’s skip falling into the road during a basement dig and a report earlier this year from the Health & Safety Executive identified that one in two basement sites in top London boroughs failed safety inspections.  It’s no wonder that building a basement is proving unpopular!

All this came to a head in January 2015 when the Royal Borough of Kensington & Chelsea applied a new planning Policy CL7.  The policy restricted the extent of basement excavation to no more than half under the garden or on part of the site and limited the depth of excavation to a single storey.  In order to control this further, the Royal Borough of Kensington & Chelsea have issued a borough wide Article for Direction in relation to basement development.  This will come into force on 28 April and will remove the right to dig a single storey basement as permitted development.  Planning permission will then be required.  If this wasn’t enough, there is a Private Members’ Bill currently going through Parliament called “Basement Excavation (Restriction of Permitted Development) Bill” which had its first reading on 16 September 2015 and is to have its second reading soon.  The scope of the Bill is not fully defined but the language used in the Parliamentary debate was very emotive.  The Bill’s sponsor said: “For we talk not of the extended kitchen or extra living space for a growing family, but of “icebergs”: projects that have, at the extreme, involved digging down several levels and hundreds of feet out for home gyms and spas, cinemas and gun rooms, and dance floors and the almost mandatory pools”. If you live in the Royal Borough Kensington & Chelsea, it seems that if you wish to dig a basement under permitted development rights you’ll have to have a material start to work on the project by 29 April.

The jury is out on whether the new basement policy will improve the conditions for local residents.  True, the construction time will be reduced as the basements will be smaller, but it won’t stop project overruns or builders ignoring the Traffic Management plans!

So what should you be doing to build your basement?  There are two big issues that need to be thought about.  The first is the effect of your construction on your neighbours and the second is how the basement is designed and the construction managed. Louisa Richter von Morgenstern of RVM & Associates highlights that “It is essential, and only good manners, to listen to, respond and take measures that address the concerns of your neighbours.” Plan your works to have the minimum construction impact and make it clear to your neighbours that this is the approach that you are taking.  Get the right team on board and at an early stage. Find a team with a proven track record of good quality design who will take proper account of construction operations (it is worth looking locally first as they will have an understanding of the area and local council).  Critically, try and involve your neighbours as much as possible. Don’t simply rely on the legal notification via planning approval phase, contact them directly and explain your plans and your intention to cause them minimal disruption. A bottle of wine can go a long way!  Don’t forget that it is highly likely that the work will require a party wall award between you and your neighbours and you may not be able to start work until the party wall award is in place.  The party wall surveyor should be engaged as part of your professional team at the beginning of the project.  Make sure that there is proper construction insurance in place.  Simon Haslam of Basement Force says “The design team need design something that not only structurally sound but is also something that can be built efficiently.”

A lot of the recent horror stories in the press have involved contractors who have gone bust following their disastrous work. It is essential to check that your contractor is financially stable and has been so for some time.  Consider using a contractor who is a member of ASUC (The Association of Underpinning Contractors). It is worth remembering that in order to build basements for the Grosvenor or Cadogan Estates, the contractor needs to be a member of ASUC.

Finally, make sure you have proper appointment and construction documentation in place.  If there should be a problem you will want the peace of mind that someone’s insurance will pay!

Ultimately, achieving as seamless and frictionless a basement build as possible, requires good planning, the best professional teams and, as importantly, keeping in with the neighbours.

Article by Stephen Rockhill, Partner.
First published in LondonLovesBusiness, March 2016

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