Pre-Construction Services in London

Pre-Construction Services

On most London projects, the weeks before anyone starts work decide more than the weeks on site. Surveys, approvals, notices to neighbours, licences and the price all have to be settled before the first skip arrives. When they aren’t, construction projects stop part-way while someone waits for a surveyor, a council or a delivery.

Pre-construction is that stage. It usually runs from the approved drawings to the start date, and takes anything from a few weeks to a few months.

Surveys and investigation

The first job is finding out what’s actually there. A measured survey for the drawings, and often a structural survey. On older houses, trial holes are dug next to the foundations to see how deep they go and what they sit on. In most of London that’s clay, which moves with the seasons and with tree roots, so the depth and the nearby trees matter.

Other checks that often come up:

• an asbestos survey before any demolition or strip-out in buildings from before 2000;
• a CCTV survey of the drains, especially if the build goes over or near a public sewer;
• a check of the gas, water and electrical supplies, and whether they’ll need upgrading.

These findings go into the price. A hidden problem found before the contract is signed is much cheaper than one found halfway through.

The client’s duties under CDM

The Construction (Design and Management) Regulations 2015 apply to all building work, including on houses. For domestic clients most duties pass to the contractor, but the regulations make clear how important the information gathered early is:

“A client must provide pre-construction information as soon as is practicable to every designer and contractor appointed, or being considered for appointment, to the project.”

Construction (Design and Management) Regulations 2015, regulation 4(4)

“Pre-construction information” means what’s known about the site: existing drawings, asbestos reports, the position of services, previous structural work. It also has to be passed on to anyone pricing the job, not only the one who wins it. The construction phase plan, which sets out how the site will be run safely, has to be in place before work starts.

Neighbours and party walls

Most London houses share a wall with at least one neighbour. Work on a party wall, or digging near a neighbour’s foundations, needs notice under the Party Wall etc. Act 1996, usually one or two months ahead. If the neighbour doesn’t agree in writing, the Act sets out what happens:

“Where a dispute arises or is deemed to have arisen between a building owner and an adjoining owner in respect of any matter connected with any work to which this Act relates either— (a) both parties shall concur in the appointment of one surveyor (in this section referred to as an “agreed surveyor”); or (b) each party shall appoint a surveyor and the two surveyors so appointed shall forthwith select a third surveyor (all of whom are in this section referred to as “the three surveyors”).”

Party Wall etc. Act 1996, section 10(1)

A “dispute” here doesn’t mean an argument. A neighbour who simply doesn’t reply within 14 days is deemed to dissent. The surveyors then agree a party wall award, which usually takes a month or two. That’s why notices are served as early as possible.

The rules weren’t new in 1996. They’d applied in London under the London Building Acts for well over a century. The 1996 Act extended them to the rest of England and Wales.

The street

London streets are tight, and anything on the pavement or road needs the council’s permission. Scaffolding is one of them:

“Subject to subsection (6) below no person shall, in connection with any building or demolition work or the alteration, repair, maintenance or cleaning of any building, erect or retain on or over a highway any scaffolding or other structure which obstructs the highway … unless he is authorised to do so by a licence in writing issued for the purposes of this section by the highway authority …”

Highways Act 1980, section 169(1)

Skips need a separate permit, and parking bay suspensions for deliveries are booked with the borough, often a week or two ahead. In controlled parking zones, contractors’ vehicles need permits too. Some boroughs have rules on working hours and noise, and big jobs may need a construction management plan as a planning condition.

Price, programme and value engineering

With the survey results and the drawings, the job can be priced properly and a programme drawn up. Long-lead items are ordered early: steel, windows and doors, kitchens, roof lanterns. Made-to-measure glazing is often 6 to 10 weeks.

Value engineering means looking at the design again once the cost is known. Sometimes a change saves a lot for little loss: a standard window size instead of a bespoke one, or a beam that sits within the floor instead of below it. The design side of this is covered on the planning and design page, and the role of the architect in the planning architect guide. What London extensions are like in practice, once building starts, is in the reality of London extensions.

Force Builders carries out surveys, pricing, programming and approvals ahead of building work on projects across London.