• BCS 4
  • 013 BG_OverstoneGate_DWH_Northamptonshire_Hertford_Lichfield_Winstone_5bed_4bed
  • Site Manager
  • Hayes Village
  • BNE_TheDrive_Durham_Construction

Trade Specifications

The following Trade Specifications must be read in conjunction with all other Contract documentation including; Tender Letter, Operating Procedures for All Contractors, Conditions of Contract for Works, Labour Only and Purchase Orders, General Construction Notes (England & Wales), Suppliers and Sub Contract Works - SLA and the Company's Occupational Safety, Health & Environmental Management System.

Our aim is to enable our sub-contractors and suppliers to access key Commercial information such as Terms & Conditions, Trade Specification, etc. online as soon as they are updated and revised. We hope that this will ensure that our supply chain is always fully informed as quickly as possible.

Whilst available online, this information is also available from the Commercial Departments at our Divisional offices and will form part of any contract we place (as set out in the Order).

Please be aware that bogus web sites seeking fees for the chance of working with major contractors exist.

Jon Hayward
Commercial Director (Group)

Brickwork

Revision Z - 01.01.2023

The installation of hedgehog holes in boundary walls in accordance with the layouts provided and to the DB-SD11-004 Hedgehog Guidance.

Tags: Brickwork

Carpentry

Revision AE - 01.01.2024

Update to reflect that the Contractor is to include within their quotation for the installation of ARC Soffit Slab, the forming of working platforms above the insulation in the roof void, patressing for the installation of PV switchgear and horizontal battening for the installation of a smoke and heat alarm in the roof void.

Minor changes have been made to the requirements to remove waste from plots to the waste segregation area and deposited into the appropriate skip. The change also notes that we reserve the right to contra-charge the Contractor for the cost of excessive removal of their waste.

Tags: Carpentry

Carpet Floor Covering

Revision B - 01.07.2018

Group carpet ranges added to Specification.

Tags: Carpet

Cavity Wall Insulation

Revision A - 01.01.2024

The specification for mineral wool insulation has been added for timber frame construction.

External walls studwork to be tightly packed to 140mm depth with mineral wool insulation (min mass 10kg/m³) with minimum Thermal Conductivity of 0.035 W/mK.

A vapour control layer to be installed on the inside of the dwelling secured by 25mm timber service batten.

Party Walls studwork to be tightly packed with absorbent material to minimum 60mm depth with mineral wool insulation (mass 10-60kg/m³) both sides, mineral wool may be unfaced or wire-reinforced.

Integral Garage Internal Walls studwork to be tightly packed to 140mm depth with mineral wool insulation (min mass 10kg/m³) with minimum Thermal Conductivity of 0.035 W/mK to achieve a U-value of 0.30W/m2K.

Ceramic Floor Tiling

Revision H - 01.01.2019

Health and Safety information has been updated and company brand information has been updated in-line with our current sales literature.

Cleaning

Revision K - 01.07.2018

Wording to match tick schedule aligned and general update of Health & Safety.

Tags: Cleaning

Demolition

Revision K - 01.08.2022

General section item h) Drug/Alcohol Testing added - the company reserves the right to test any persons on our sites for alcohol and drugs. Anyone who refuses to participate in any sampling being undertaken on site, will be asked to leave the site immediately and prohibited from working on any of the company's sites until non-negative tests have been provided.

The contractor must have an appropriate policy in place and have a programme of sampling of their workforce. From the 1 January 2023, 25% of the contractors' workforce on the company's sites must be randomly tested every 6 months. The contractor is to make reference to SHE Form 09 for policy on those individuals who provide non-negative samples.

Drylining Coving Screed

Revision AK - 01.07.2023

General section has been updated to enhance the requirement for material protection; to ensure that materials are "protected with a proprietary reusable fire-resistant double pallet cover in order to avoid damage and surface contamination."

Internal walls to garages specification has been amended to account for the discontinuation of British Gypsum Thermaline Super insulation bonded to 9.5mm plasterboard, the new Thermaline PIR board comprises 40mm PIR insulation bonded to 12.5mm plasterboard.

The section on waste has been updated to reduce the waste created by offcut plasterboard material on all wallboards, Contractors must use 2300mm boards where available.

Electrical

Rev AS - 01.01.2024

General section has been updated to request that the Electrical Contractor works in conjunction with the Plumbing Contractor to ensure the wiring locations are appropriate and all necessary connections are completed for all items supplied and installed by the Plumbing and Heating Contractor requiring connection to either mains power or to data points. Additionally, where condensation traps and drain are to be installed by the Electrical Contractor to the ventilation duct, in readiness for the Plumbing Contractor to connect the drain to the SVP.

Changes have been made to the installation of Virgin Media O2 fibre.

Sections 16 and 17 have been combined into one, Mechanical Extract Ventilation. The section has been fully updated to 2021 Building Regulations. Product codes have also been updated, for ordering by the Contractor, in the schedule of materials section.

Smoke Alarms, this section has been amended with the addition of mains powered combined smoke and heat alarms must be installed in roof spaces where Solar PV, inverters, batteries, or boilers are installed.

Minor changes have been made to the requirements to remove waste from plots to the waste segregation area and deposited into the appropriate skip, this also includes a contra-charge provision if not completed satisfactorily.

Electrical Downlighter Installation

Barratt / David Wilson Homes Standard Drawing DB-SD09-003

Fencing

Revision N - 01.01.2024

Section 13 Timber Surveys has been added to require the Contractor to provide annualised returns of FCS/PEFC within 14 days of request by the relevant operating Division by accurately completing and returning the standard form.

A new waste removal section has been added for the removal of waste from around the plot to the segregation area.

Tags: Fencing

Fire Proofing

Revision B - 01.02.2022

Revised document updated in accordance with Group Fire Safety and Group Technical.

Glass Balustrades

Revision C - 01.02.2022

General section – a) with reference to the procurement of materials, installation of materials and on-site working methods to ensure the correct standards and compliance is achieved on site. This trade specification is to be read alongside working drawings, BDW Standard Details, manufacturer's literature and the Barratt Construction Best Practice Guide.

Defective Workmanship – e) with reference to works undertaken by a preceding trade.

Sub-Contractor – i) where fire proofing or fire stopping measures are likely to follow this trade, it is essential the preparation work is sufficiently prepared.

2.1 Fire Spread – Where glass balustrades will form part of an External Balcony. Refer to Divisional Technical / Group Technical for specific requirements.

Sign off clause updated.

Landscaping

Revision J 01.01.2024

The requirement for all soils and trees to be sourced peat free in accordance with UK legislation has been added.

The requirement for tree stakes has been updated in subsection 8.3.

Mulch has been amended where the size and specification of the bark has been added.

A new waste removal section has been added for the removal of waste from around the plot to the segregation area.

Loft Insulation

Revision O - 01.07.2021

General Item g) Health & Safety. The Contractor's attention is drawn to the Health and Safety section of this Loft Insulation Trade Specification which has been rewritten in accordance with Group Health & Safety requirements.

Section 5. The Contractor's attention is drawn to the Waste Removal & Cleaning Out section of this Loft Insulation Trade Specification which has been re-written in accordance with Group Health & Safety requirements.

Mastic

Revision Q - 01.08.2020

External Mastic. Clarification has been added to 2.1 (v) around perimeter of integral garage ceilings and perimeter of shared double garages with the use of intumescent sealant.

Internal Mastic. The following requirement has now been deleted in section 4.1 (i) The joint between the masonry wall and the timber joists and any other air path to the external face of the structure are to be carefully sealed with silicone sealant if the joists are not on hangers or shoes but built in to masonry wall.

Tags: Mastic

Painting and Decorating

Rev AB 01.01.2024

Within the preparation of surfaces section, the initial Trade Supermatt mist coat can ONLY be sprayed if completed before 2nd fix stage.

Plot Groundworks

Revision AA 01.01.2024

Above ground drainage distribution has been changed and Pre-Insulated Floor Cassettes have been added.

The specification class for inspection chambers, drainage channels, frames and drain covers within private and shared driveways has been updated to be a minimum of B125. An additional note has been added that, pedestrian routes should be completed with a minimum specification class of A35. Additionally, channel drainage located within shared drives should have covers installed to accept loadings equivalent to class C250.

A number of other sections have been updated to note the additional pricing information, record keeping and testing requirements for the Contractor to provide this to BDW Site Management.

Subsection 11.17 has been changed to note the spacing of vertical wall ties from 600mm to 450mm.

Plumbing and Heating

Rev AU - 01.01.2024

Distribution has been changed to City Plumbing Supplies Ltd.

A change has been made to the requirement for the Plumber to work in conjunction with the Electrical Contractor for all the necessary connections to either mains power or to data points. The Plumbing and Heating Contractor must also work in conjunction with the Electrical Contractor to connect any condensation trap to the Soil pipe in the roof void at 2nd fix stage.

The preference to use straight lengths of plastic pipe are preferred to coils has been removed.

An amendment has been made to note gutter brackets are to be installed using a minimum of two screws per bracket. Additionally, expansion gaps must be provided for gutters in all fittings and fixtures as shown on manufacturers fitting instructions.

Reference codes and locations have been added for isolation valves.

Following changes to the bath dimensions in the David Wilson Homes specification an amendment has been made to waste pipe access, subject to the dimensions of the bath.

Pre-Cast Concrete Floors

Revision - 01.01.2018

Pre-Cast Hollowcore Concrete Plank Floor trade specification.

Render

Revision H - 01.07.2017

Product codes/names have changed.

Tags: Render

Roads & Sewers Stage 2

Revision M - 01.01.2024

Section 2 Guidance Notes, subsection 2.3 has been deleted as it is repeated from section 2.2. The renumbered subsections 2.3 and 2.8 have been amended to add requirements for testing and Water Authority requirements.

Subsection 2.15 has been amended to add requirements for test certificates being provided for all imported material at the point of delivery confirming that all materials are supplied in accordance with specification. Additionally, where CBR tests are required on road formations, plate tests on capping and sub-base and plate tests on drainage trench backfill, these must be allowed in accordance with LA requirements and the results shall be provided to BDW for inspection prior to any stage payments. In the absence of LA guidance this shall be carried out at 20m intervals.

Section 3 Pre-Start Investigation. Subsections 3.5 and 3.6 have been added.

Section 5 Setting Out. Subsection 5.2 has been added to require the Contractor to confirm the required local scale factor for the site and the local stations to be used for setting out the site. The Contractor shall ensure all existing ground levels are in accordance with the survey provided, paying particular attention to highway tie in points and any boundary points of interest.

Section 10 Drainage. Subsection 10.10 has been inserted to ensure an appropriate quality of works check is carried out on all drainage, manholes and inspection chambers. Documented evidence of this shall be provided to BDW prior to laying of base course and shall include as a minimum that manholes are built to the specified details, CCTV of drainage runs has been reviewed and any defects or damaged items have been removed and rectified.

Section 13 CCTV and As Built Surveys. Subsection 13.1 has been amended to include gulley connections and lateral pipes if so required by the Adopting Authority. Subsection 13.3 has been added to require the Contractor to provide a comprehensive information pack and issue to BDW.

Section 14 Capping Layer. Subsection 14.2 has been updated to include allowance for any testing that may be required.

Section 15 Roads / Parking Areas / Shared Access. Subsection 15.6 through to 15.10 have been added requiring the Contractor to maintain records for the installation, testing of materials and completion surveys.

Section 16 Concrete Kerb Race. Subsection 16.2 has been updated to require the Contractor to provide fully co-ordinated as-built details to the BDW Site Manager prior to stage payment.

Section 18 New Road and Street Works Act. Subsection 18.3 has been updated to require the Contractor to include the protection of existing watercourses and outfalls from the ingress of deleterious substances within their quotation.

Roads & Sewers to Binder Course inc. stage 2

Revision R - 01.01.2024

Subsections 1.4, 1.5, 1.6, and 1.8 have been added to require the Contractor to provide detailed cost analysis of the impact of any potential adjustments to drawings and include within their quotation all works associated with setting out from co-ordinates provided by the Company, testing of materials provided by them and test certificates.

Subsection 1.9 has been added to request that the Contractor ensures phased inspections of the works are arranged with the adopting authority in accordance with the adopting authority requirements.

Section 6 Wearing Course. Subsection 6.4 has been added to request records for the binder and surface course shall be provided by the Contractor for each visit and must be provided prior to stage payment.

Roof Tiling

Revision AE 01.01.2024

Section 2 has been amended to advise that all underlay must have 3rd party accreditation by BM TRADA, KIWA, BRE or BBA.

Amendments have been made to instruct the Contractor to neatly cut through the roof, including panellised roof systems and supply and install the vent terminal including adaptor through the underlay in readiness for connection by others.

Due to a requirement for ventilation terminals to meet the requirements for Mechanical Extract Ventilation, the use of 3rd party products is only permitted where approval has been provided by the tile manufacturer.

Roofing Contractor is to provide and install expanding foam tape to dormers, and chimneys to fill the gap at any exposed tile edges to prevent ingress into the roof from wildlife and driving rain.

Scaffolding

Revision U - 01.01.2023

The previous 'change applicable from' date has been removed.

Solar PV

Revision A - 01.01.2023

Group Supplier details added.

Tags: Solar PV

Special Projects Concrete Works

Revision H - 01.08.2022

Section 16.33 item added – the company reserves the right to test any persons on our sites for alcohol and drugs. Anyone who refuses to participate in any sampling being undertaken on site, will be asked to leave the site immediately and prohibited from working on any of the company's sites until non-negative tests have been provided.

The contractor must have an appropriate policy in place and have a programme of sampling of their workforce. From the 1 January 2023, 25% of the contractors' workforce on the company's sites must be randomly tested every 6 months. The contractor is to make reference to SHE Form 09 for policy on those individuals who provide non-negative samples.

Vinyl Tile, Sheet & Laminated Flooring

Revision I - 01.07.2018

Minor notes under section 4 added regarding floor types used within the group.

Wall Tiling

Revision I - 01.07.2017

Formatting changes only.

Window Installation

Revision H - 01.01.2023

Group Suppliers – Contact name and telephone number updated.