Planning Application for basement - help me find a soil analyst

[BusyBusyBusy1]

Hello, has anyone put in a planning application for a basement? Did you have a soil analysis and structural engineer report? If so, can anyone recommend someone (in London area). Thank you

Try contacting an Encironmental Surveyor.

you can get a recommendation for a structural engineer via the IStructE website. All structural engineers will know of, and have relationships with, companies that do the ground investigation work.

However, if you are only at the planning permission stage, have you engaged an architect? They usually have structural engineers they use and ground investigation companies as well

Thanks Socks and Wow. Yes we have an architect but they seem to be taking time to find someone who charges a reasonable price - the quote so far is well over a grand.

What are you expecting to get for £1k? Or rather, what are you wanting done?

Hi Socks, ummm I am not really sure what we need for the planning app - it is the first time we have put in a basement application. The house is a very ordinary 2 storey 3 bed, and I am guessing it is built on clay like the rest of London! The plans are for a single storey extra room covering about half the footprint of the house - so not very ambitious. Our architect seems to be taking some time so just wondered if I can do anything to speed up the process.

For a planning application, you don't really need a structural engineer or a ground investigation - these would come into play when you have permission and need to submit a building control application. I would go back to your architect and ask them for a timetable of what they think you will need. However, my DH is a structural engineer (as am I but I do LA work not private jobs), he would normally charge £70-80/hour so £1k doesn't get you as far as you might think. Site visit, initial design, drawings, liasing with BC and architects, answering queries from contractors, site supervision etc. However, if you get a good local engineer they may not need a ground investigation if they have enough knowledge about the ground conditions.

Do you have someone to advise you on all of the 'extras' like building regs and party wall issues? I've just arranged a couple of soil inspections, but it isn't a given that they're needed. Usually the structural engineer will request that they happen. Hopefully your design & build people can put you in touch with someone, or I know a company you can try but it depends which side of London you are....

If it's just the basement you are having done I would be inclined to use a specialist basement company. We have had a basement put in recently and it was all a bit of a mess - mainly I suspect because neither the architect or the structural engineer really knew what they were doing. In the end we have a nice space but it was very painful - way over time and budget.

You do need a structural engineer for a basement planning application, the Council will want to see that it's in principle, no going to harm the property or the neighbours. Please engage a good one who has experience of similar early on in your process, a grand is also not expensive.

If you're in an archaeological priority area you'll need an archaeology desk based assessment too.

Do not scrimp on these things - do you want to cause damage to your it your neighbours property?

Why don't you phone the planning officer to find out what they expect.

Depending on where you live in London there can be significant water table issues (London is built on clay) or historical/archological issues. Local planning officers will know the local problems and what reassurance they will need at planning stage. Better that way, in that otherwise any planning consent would be conditional on further investigations.

Also agree with poochie, that you will almost certainly need a structural engineer, as you presumably will have party wall issues, and he will guide you through.

Have you spoken to neighbours? Planners usually like to see applicants carry out local consultation and address local concerns as best they are able, rather that let the row break out in the planning committee.

Watch your architect. There are a few design and build merchants who seem to cross their fingers and hope no one will ever pull them up on boring stuff like party wall agreements, building control permission, or freeholder permission. Chickens then only come to roost if a future purchaser asks for paperwrok or if cracks appear and the insurer starts questioning.

If you're getting edgy about £1k and a few communication delays I'm not sure a basement conversion is for you.

It will cost a minimum of £175k and take at least 12 months once you've factored in all the project creep that happens with every basement conversion. You'll also need to live elsewhere for the duration of the build. Make sure your neighbours love you because they can make life unbearable for you afterwards in revenge for the misery you'll put them through during works. I can think of at least three clients who have had to sell up and move immediately afterwards because the relationship became so toxic. The nominal profit disappears very quickly in stamp duty on your next place.

£1k... I think I would bite their hand off at that price. There is a lot of work in a basement for the structural engineer, more complicated than a single storey rear extension. I think you need to do some reading up about the work involved as I think you may have unrealistic expectations of the project and may well end up very disappointed or much more out of pocket than you expected. 1k for the calculations and the professional indemnity insurance, if something goes wrong you'll be wanting to sue them and your whole house is on top of the basement so the significance if something goes wrong is massive. Make sure whoever you employ is chartered with IStructE and can use the designation MIStructE and make sure the amout if the professional indemnity insurance is greater than the reinstatement cost of your and your neighbours properties combined if you are in a terrace.

In London for a basement extension, you will need to pay out a lot of professional fees to get the reports together for Planning. Regulations have been tightened up as concerns grow about inconvenience to neighbours, ground water and flood risk. The list of requirements depends massively on which borough you are in - if you are concerned about £1k fees then give up now. If you are in an outer london borough you will be looking at several thousand for the architect; maybe £4-5k for an engineer to do a Basement Impact Assessment and then a further £6-8k for the geotechnical boreholes and report. It is essential that you choose a team who have worked on basements together before and you need to ensure you choose a contractor who is a registered member of the society of underpinning contractors...... TBH I think you would be best off going to the London Basement Company who are a one-stop shop who can do all the design and construction for you without you having to worry about the interfaces between appointments and contracts. Basements regularly go wrong (sorry to be gloomy but water usually wins if there is a slight chink in the waterproofing armour) so don't try to do it on the cheap. This is major structural work and lots of architects will not be able to handle the level of complicated technical detailing required.

As a warning look here for people who picked a random builder to underpin their house and were then surprised that disaster struck (doh)