Best practice guidance on construction standards and procedures
This is the Knightsbridge Neighbourhood Forum's 'Best practice guidance on construction standards and procedures'. It should be read alongside 'Policy KBR22: Construction activity' in the Knightsbridge Neighbourhood Plan (the KNP, Neighbourhood Plan or the Plan).
1.1 In preparing the Knightsbridge Neighbourhood Plan, the Knightsbridge Neighbourhood Forum (the Forum, KNF or Neighbourhood Forum) has also produced best practice guidance on matters such as community engagement, construction standards and procedures and Tree Management Plans. The contents of this guidance was consulted upon during the Regulation 14 and Regulation 16 consultations on the Neighbourhood Plan.
1.2 Where this guidance includes matters that relate to planning applications rather than procedural matters, they will be treated as material considerations. Unlike the Neighbourhood Plan however they do not have development plan status.
1.3 The following construction standards or procedures are intended to complement Westminster City Council's (WCC’s) Code of Construction Practice and assist in the implementation of Policy KBR22 (Construction activity). Regard should also be had to the recommendations on 'Industry Practices' from the Institution of Civil Engineers (London) in its report titled 'Engineering Cleaner Air' (dated October 2017) including pages 42-60.
1.4 These measures should be applied on a case-by-case basis and in a way that meets the tests set out in paragraph 206 of the NPPF to medium or major development. In certain circumstances it may be appropriate or necessary to apply some of them to all development.
1.5 They can be addressed in: planning conditions; a Construction Management Plan (CMP) or similar document approved by WCC; or a separate planning obligation e.g. s106 agreement.
1.6. WCC published the 'Intend to Adopt' version of its new City Plan in March 2021 which addresses construction matters in a number of policies including 33. Local environmental impacts (F) and (G).
2.1 A draft Construction Management Plan (CMP) or other draft proposed commitments must be submitted with the planning application. Developers should use reasonable endeavours to consult the Knightsbridge Association (KA) early on in planning their deconstruction and construction activity and agree it with the KA. Relevant legal agreements must be in place before any works commence on site.
2.2 One or more Traffic Marshalls are required to manage safely all vehicle movements to and from the site and ensure that vehicles comply with local access and egress requirements including in relation to timing.
2.3 Proposals must demonstrate and confirm after appropriate investigations that they will not adversely affect neighbouring properties, underground streams, water courses, water tables and/or the Piccadilly Line of the London Underground or disturb any contaminated land. They must also confirm that there is adequate clean and dirty water drainage capacity onsite and locally up to and including the nearest node or branch to the site to meet fully the expected needs of the development during deconstruction and construction. The engineering aspects of an extension or development must be considered separately from the main development plan.
2.4 The developer is expected to write to the 25 nearest properties and provide a 24-hour telephone number to report dusty, noisy or inconsiderate works.
2.5 Air quality ‘tool box talks’ are required with the following content as a minimum: ‘eco driver’ training; travel plan for all staff focused on air quality and reducing noise; and advice for staff on how they can reduce their personal exposure to emissions and noise and protect the local community from them.
2.6 Developers and their agents, contractors and suppliers must comply fully with the most up-to-date best practice in the Considerate Constructors Scheme particularly in relation to measuring, managing and minimising the impact of vibration and air, light and noise pollution. Scores of 35 or above out of a maximum possible score of 50 should be required and displayed to the public on the site notice board.
2.7 Deconstruction and construction activity must minimise both the health and safety impacts of the development for employees, contractors and other staff and the local community. Focussing only or primarily on the safety aspects will be insufficient to comply with this requirement.
3.1 All vehicle access to the site must take place along Main Roads (i.e. the Transport for London Route Network (TLRN) and the Strategic Road Network (SRN) including the A315), suited to such movement, as opposed to narrow residential streets in order to protect residential amenity. This includes the need to reverse down narrow two-way residential streets (e.g. Cheval Place and Montpelier Street) and/or turn and reverse at the next closest junction to allow forward movement back down the shortest route on such roads.
3.2 If the primary address of the development is on a Main Road (e.g. Brompton Road, Exhibition Road or Knightsbridge) then all construction work should take place on that road not on or through narrow residential roads.
4.1 All vehicles using narrow residential roads must have a maximum gross weight of five tonnes and two axles unless no alternative exists. Alternative vehicles may only be used if the developer demonstrates and confirms in writing that no practical alternative exists and that no significant damage would be caused if the alternative is used e.g. to weak under-pavement vaults or old buildings along the access and egress routes.
4.2 Proposals for construction activity must include a wheel track plan to demonstrate and confirm, for all vehicles to be used, that they can access the route without crossing or touching pavements, parked vehicles or street furniture.
4.3 All vehicles should meet or exceed the Euro 6/VI engine emission standard when operating in the Knightsbridge Neighbourhood Area (Area) from 8 April 2019. Applications for construction activity are also expected to use vehicles that comply with the following standards: (a) ultra low or zero emission HGVs must be used with the Area once technically feasible and commercially viable (e.g. hybrid-engined diesel/electric in electric mode or electric only trucks); and (b) all construction vehicles including delivery, skip and scaffolding vehicles should be accredited at least for: (i) the latest Silver or Gold level as updated from time to time of Transport for London’s (TfL’s) Fleet Operator Recognition Scheme (FORS); and (ii) the latest applicable Direct Vision Standard as updated from time to time by TfL for Heavy Goods Vehicles entering the Central London Congestion Charging Zone.
4.4 No engine idling of vehicles is permitted near the site or on residential roads.
4.5 The Traffic Marshall must ensure that all vehicles carrying waste from the site cover the truck tray or platform before it leaves the site to minimise dust.
4.6 ‘Just in time’ arrival of construction-related vehicles on residential roads must take place no more than 10 minutes before the hours permitted for noisy works by Westminster City Council. ‘Just in time’ departure and egress of vehicles must take place no more than 10 minutes after the hours permitted for noisy works.
4.7 Skip, scaffolding and other vehicles must only access residential roads and operate within the hours permitted for noisy works and arrive no more than 10 minutes before the hours permitted for noisy works. ‘Just in time’ departure and egress of such vehicles must take place no more than 10 minutes after the hours permitted for noisy works.
4.8 Construction, freight and delivery consolidation centres or similar shared storage facilities for materials must be used during deconstruction and construction for all major projects to minimise the number of vehicle movements in the Knightsbridge Neighbourhood Area and Greater London.
5.0 Non-road mobile machinery (NRMM)
5.1 Contractors must comply fully with the requirements of the Greater London Authority (GLA) SPG or better for the ‘Control of dust and emissions during demolition and construction’ including Non-Road Mobile Machinery (NRMM) for the Core Central Activities Zone throughout the Knightsbridge Neighbourhood Area. All plant must be registered and conform fully to GLA standards or better or not be used. These include for the use of NRMM with net power between 37kW and 560kW for both variable and constant speed engines a requirement to meet or exceed for both oxides of nitrogen (NOx) and particulate matter (PM): (a) Stage IV of EU Directive 97/68/EC and its amendments for activities undertaken from 28 February 2021; and (b) the registration requirements on the website nrmm.london to help monitor, manage and report the use of such equipment across London or obtain block, viability or short-term exemptions where applicable. In most cases, variable speed engines smaller than 56kW will need to meet Stage V. These standards will get progressively tighter over time.
5.2 The KNF encourages developers to consider using the latest available all-electric construction vehicles such as those in JCB's 100% electric E-Tech range.
5.3 Developers should demonstrate an audited hierarchy of selection for NRMM used in construction. First criteria should be to avoid the use of plant that generates on-site emissions by changing the method of design to avoid the need for plant in the first place. Where plant operates it should be of hybrid type which uses the latest available technology for maximum on-site emission abatement. It should also use ultra low sulphur diesel or cleaner fuels (to minimise both PM and NOx emissions). No diesel or hybrid plant should be used onsite unless there is no practical alternative and it is major plant fitted with a diesel particulate filter using the latest available technology for maximum on-site emission abatement.
5.4 Controls should be in place for generator running times to ensure they are shut down when not in use. There should be no engine idling of all plant and equipment as standard.
5.5 A conveyor belt system or 'hand dig' shall be used for soil removal from residential properties to a skip sitting in the street to minimise vehicle or machine operations unless it is impractical.
6.0 Minimising onsite emissions, noise and vibration
6.1 Noisy work that can be heard at the boundary of the site should only be carried out between 08:00 and 18:00 Monday to Friday (excluding bank and public holidays). Noisy work must not take place outside these hours.
6.2 Prefabricated and other off-site processes should be used to make the construction process quicker, safer and cleaner e.g. offsite drilling and cutting.
6.3 The lowest emission and vibration technique should always be used on-site unless it is impractical e.g. diamond-blade cutting, membranes or fibreglass not asphalting of flat surfaces and stationary jaw crushing not jack hammering of concrete.
6.4 The use of electric power from the grid for all works on-site, including demolition, must be considered with the electricity provider during the design stage of the development and addressed in the Construction Management Plan in order to minimise local emissions and noise and vibration. The developer must demonstrate that contact has been made and reasonable notice given to the electricity provider to support this requirement.
6.5 Regular monitoring of hourly mean PM2.5 and PM10 concentrations and noise on site boundaries may be required for medium and larger developments if sensitive receptors could be affected. In such cases, the contractor should either undertake this activity themselves or link it in with wider monitoring being undertaken by WCC. Noise monitoring should be included in any Section 61 Noise Application for medium or major developments. Developers should make this information available on their website for the development.
7.0 Street management
7.1 ‘Best efforts’ should be used to minimise the effects of the following: congestion; damage to clean and dirty water drains, pavements, streets, street furniture, under-pavement vaults and old buildings along access and egress routes; dust, dirt and grit on pavements and streets; emissions to air, land and water (including ‘down the drain’ waste); impacts on local residents’ quality of life; inconvenience to pedestrians (e.g. due to hoardings); light pollution; noise; residents’ parking; vehicle movements; and vibrations. Developers are advised, for example, to contact Thames Water at an early stage to discuss water and sewerage infrastructure requirements (see paragraph 5.6 of the Knightsbridge Neighbourhood Plan for more details).
7.2 Investigations and a photographic audit around site and along access and egress routes in residential roads should be undertaken before any works commence i.e. street lights, gullies and connections from them to Thames Water’s sewer, footpaths, footways and carriageways. All efforts should be made to minimise impact. Impacts should be properly and fully monitored throughout the lifetime of the construction activity and, where necessary, timely ongoing repairs should be made. An audit of activity should be completed after construction activity has ceased after which all outstanding repairs are to be completed promptly.
7.3 Specialist vehicle(s) should be used to vacuum and water wash the entirety of any access and egress routes in narrow residential roads at least weekly to eliminate dirt, dust, grit and sharps from the road surface. A hand sweep and wash (or use of an appropriate machine) should be undertaken near the site as needed but at least on each working day and, if needed, along the whole length of narrow residential roads used. Particular care should be taken to remove on each working day any nails, screws or other sharp materials on pavements or streets.
7.4 Contractors should consult the Knightsbridge Association if streets are to be blocked or closed. In such circumstances, a circular should be delivered to all properties along the routes in question at least seven days beforehand to explain what works are intended and how impacts will be minimised for local residents and businesses.
The Neighbourhood Plan's 'Appendix A: Glossary' includes definitions e.g. medium and major development.
Useful resources (added 19 November 2020)
London Collision Map (11 January 2021)
Air Quality Focus Area 2016 (15 February 2021)
Updated on 27 July 2021 to refer to the use of membranes on flat roofs.