CDM Regulations and the Quantity Surveyor

How CDM 2015 affects the QS — duty holder responsibilities, cost implications, and pricing H&S requirements

Introduction

The Construction (Design and Management) Regulations 2015 (CDM 2015) are the primary legal framework governing health and safety management on construction projects in Great Britain. They place responsibilities on every party involved — client, principal designer, principal contractor, designers, and contractors — to plan, manage, and monitor health and safety from concept to completion. For the quantity surveyor, CDM is not someone else’s problem. The QS is classified as a designer under CDM 2015, and more importantly, CDM requirements generate real, measurable costs that must be identified, priced, and managed throughout the project. Welfare facilities, scaffolding, edge protection, temporary works, hazardous material removal, site security, training, and H&S file preparation all have cost implications — and the QS is the person who puts numbers to them.

What CDM 2015 Requires

CDM 2015 came into force on 6 April 2015, replacing the previous CDM 2007 framework. The regulations sit under the Health and Safety at Work etc. Act 1974 and are enforced by the Health and Safety Executive (HSE). The core principle is straightforward: health and safety must be planned, managed, and monitored at every stage of a construction project. The regulations apply to all construction projects in Great Britain, regardless of size or duration — though the obligations scale with project complexity.

Projects are notifiable to the HSE (via Form F10) if they will last more than 30 working days with more than 20 workers on site at any one time, or will exceed 500 person days of construction work. Notifiable projects carry additional requirements around welfare facilities and documentation. The official HSE guidance document, L153 “Managing health and safety in construction”, provides comprehensive direction on compliance.

The Five Duty Holders

CDM 2015 identifies five duty holders, each with defined responsibilities based on their position in the project.

The Client is the person or organisation having the construction work carried out. They must appoint a principal designer and principal contractor (on projects with more than one contractor), provide pre-construction information about the site and project, ensure adequate time and resources for H&S planning, and ensure welfare facilities are in place before construction starts. If the client fails to make these appointments, the client assumes the duties themselves. Domestic clients (individuals having work done on their own home, not as part of a business) have reduced obligations — most duties transfer to the contractor or principal contractor.

The Principal Designer has control over the pre-construction phase. They plan and manage design risk, coordinate with all designers to ensure H&S risks are eliminated or controlled, compile pre-construction information, and prepare the H&S file that will be handed to the client at practical completion. The principal designer is usually an architect, engineer, or specialist design consultant.

The Principal Contractor has control over the construction phase. They prepare the construction phase plan before work begins, manage day-to-day H&S on site, coordinate all contractors, ensure site inductions are delivered, and maintain welfare facilities. On projects involving high-risk activities — work at height, demolition, confined spaces, work near water — the construction phase plan must include detailed management arrangements for these risks.

Designers include anyone whose work involves preparing or modifying designs, drawings, specifications, or bills of quantities. Architects, engineers, and quantity surveyors all fall within this definition. Designers must consider H&S implications during their work and inform the principal designer of any risks that cannot be eliminated.

Contractors are any organisations or individuals carrying out construction work. They must plan and manage their own H&S, cooperate with the principal contractor, follow the construction phase plan, and ensure their workers are competent and inducted.

The QS as Designer

Quantity surveyors are explicitly classified as designers under CDM 2015 because they prepare bills of quantities, produce cost information, and specify materials and standards (indirectly, through cost selection). This classification carries specific duties: the QS must not begin work unless satisfied that the client understands their CDM duties, must consider H&S information when preparing costs and specifications, and must inform the principal designer of any cost or specification changes that might create new H&S risks.

In practice, the QS’s design duties are less onerous than those of architects or engineers — the QS does not design the physical structure. But the QS’s decisions about what to include in the BOQ, how to specify temporary works, and how to price welfare and safety provisions directly affect how safely the project can be delivered. A BOQ that underprices scaffolding or omits welfare facilities creates pressure on the contractor to cut corners. For more on how the QS prepares bills of quantities, see our article on NRM 2: A Practical Measurement Guide.

Pre-Construction Information

Pre-construction information is the package of H&S-relevant data about the site and project that the client provides to designers and contractors. It typically includes details of existing structures and their condition, ground investigation data, historical information (previous uses, contamination, hazardous materials such as asbestos), service drawings and underground utilities, access and egress constraints, site logistics, and any unusual project-specific hazards.

For the QS, pre-construction information is critical to accurate cost planning. It identifies what temporary works are needed (scaffolding, propping, edge protection), what specialist costs may arise (asbestos removal, contaminated ground remediation), what welfare facilities must be provided, and what access constraints may increase labour costs. A QS who receives pre-construction information late — or not at all — will produce an unreliable cost estimate. The QS should actively request this information from the principal designer at the earliest opportunity.

The Construction Phase Plan

The construction phase plan is a written document prepared by the principal contractor before construction begins. It sets out the site-specific H&S arrangements: management structure, site rules, induction arrangements, welfare facilities, traffic management, site security, emergency procedures, and specific control measures for high-risk activities. The plan must be realistic and proportionate — a small domestic extension needs a simpler plan than a major commercial development.

For the QS, the construction phase plan has direct cost implications. Every element of the plan — welfare cabins, scaffolding, edge protection, traffic management, security fencing, first aid provision, training — represents a cost that should be identified in the preliminaries. The QS should review the construction phase plan (or its draft) at tender stage to ensure the preliminaries pricing is adequate. Underpriced H&S provisions lead to either non-compliance (an HSE enforcement risk) or contractor claims for additional cost.

The H&S File

The H&S file is a living document prepared by the principal designer, containing information that will be needed for the safe maintenance, cleaning, alteration, refurbishment, or demolition of the building after practical completion. It includes information about residual H&S risks not eliminated through design, hazardous materials and their locations, structural information and safe working loads, equipment operating procedures, and emergency procedures.

The H&S file must be started during the pre-construction phase, updated throughout design and construction, and handed to the client at practical completion. Under JCT SBC 2024, the contractor cannot achieve practical completion without having supplied all required H&S file information. The cost of preparing the H&S file — principal designer time, specialist input, documentation — should be identified in the cost plan. On larger projects, this is typically 1–2% of design fees or a fixed fee. For more on what happens at practical completion, see our article on Practical Completion and Defects Liability.

Cost Implications for the QS

CDM requirements translate directly into measurable costs that the QS must identify and price. These costs typically sit within the preliminaries, though some (such as hazardous material removal) may be measured as specific items in the BOQ.

Welfare facilities. Toilets, washing facilities with hot water, heated rest rooms with seating and tables, drying rooms for wet weather work, drinking water, and secure storage for personal possessions. These are provided through temporary hire of modular cabins, with costs driven by project duration, site location, worker numbers, and seasonal requirements. On a typical 18-month project with 30–50 workers, welfare provision can represent a significant preliminaries item.

Scaffolding and edge protection. Full scaffold for external works, internal working platforms, edge protection systems (railings, netting, catch platforms), temporary stairs and ramps. Scaffolding costs vary enormously — from minimal on a single-storey extension to 5–15% of overall project cost on complex multi-storey refurbishments. The QS must understand the scaffolding strategy early to produce reliable estimates.

Temporary works. Propping and shoring of existing structures, ground stabilisation, dewatering systems, temporary barriers and hoardings. These are often project-specific and must be informed by pre-construction information about site conditions. For more on how preliminaries and temporary works are structured, see our article on Preliminaries and General Items in Construction.

Hazardous materials. Asbestos removal (licensed specialist work, expensive and programme-critical), lead paint containment and disposal, contaminated ground remediation. These costs can be substantial and must be identified through pre-construction surveys. Late discovery of asbestos is one of the most common causes of cost overrun on refurbishment projects.

Site security and logistics. Perimeter fencing, gate security, CCTV, traffic management (vehicle routes, pedestrian segregation, banksman provision), and site signage. These costs increase with site complexity, urban location, and public interface.

Training and induction. Site induction for all workers, specialist training for high-risk activities (working at height, confined spaces), toolbox talks, and ongoing H&S supervision. The principal contractor bears these costs, but they should be reflected in the preliminaries allowance.

CDM adviser/coordinator fees. Where the client or principal designer engages specialist CDM advice, the fees should be identified in the project cost plan as a professional fee item.

Common Issues

Underestimated H&S costs. The most common issue is failing to price CDM requirements adequately in the cost plan or BOQ. Welfare facilities, scaffolding, and temporary works are often underestimated, particularly on refurbishment projects where existing conditions create additional complexity. The QS should benchmark H&S costs against comparable projects and challenge any allowances that seem unrealistically low.

Late discovery of hazardous materials. Asbestos, lead paint, and contaminated ground are frequently discovered during construction rather than at pre-construction stage, because surveys were inadequate or not commissioned. The cost impact can be severe — licensed asbestos removal is expensive and delays the programme. The QS should advise the client to commission comprehensive surveys early and ensure the results feed into cost planning.

Inadequate welfare facilities. Contractors sometimes undersize or under-provide welfare facilities to reduce preliminaries costs. This is both a legal compliance risk (HSE enforcement) and a worker welfare issue. The QS should verify that welfare provision is adequate for the projected workforce and project duration.

H&S file not completed at PC. The H&S file is frequently incomplete at practical completion, causing delays to the PC certificate. The QS should flag the H&S file requirement to the principal designer and contractor well before anticipated PC and ensure costs for its preparation are included in the project budget.

Practical Tips

Request pre-construction information early. The QS needs site surveys, ground investigation data, asbestos reports, and service drawings to produce reliable cost estimates. Chase this information from the principal designer at the earliest opportunity — do not wait for it to be volunteered.

Price CDM costs explicitly in the preliminaries. Welfare facilities, scaffolding, temporary works, site security, and training should all be identified as separate items in the preliminaries, not buried in the contractor’s overhead percentage. This gives the client visibility of H&S costs and ensures they are adequately funded.

Review the construction phase plan for cost adequacy. When the principal contractor produces the construction phase plan, the QS should review it alongside the preliminaries pricing. If the plan describes welfare facilities, scaffolding strategies, and traffic management arrangements that exceed what was priced, there will be a cost gap.

Advise on asbestos surveys early. For any refurbishment project involving pre-2000 buildings, the QS should recommend a refurbishment and demolition asbestos survey before cost planning begins. The cost of the survey is modest compared to the cost of discovering asbestos during construction.

Track H&S file progress. Ensure the H&S file preparation is on the principal designer’s programme and that the contractor is providing the required information. Late completion of the H&S file delays practical completion — which delays retention release and the final account. For more on how risk management informs project delivery, see our article on Risk Management Tools and Techniques.

APC Relevance

CDM knowledge falls within the RICS APC Health and Safety mandatory competency, which requires candidates to demonstrate understanding of H&S legislation (including CDM 2015), the duty holder framework, and how H&S requirements affect cost management and contract administration. Candidates should be able to explain the five CDM duty holders and their responsibilities, describe how CDM requirements translate into project costs, discuss their role in pricing welfare facilities and temporary works, and demonstrate how they ensured CDM compliance on a real project. The competency is assessed at Level 2, requiring practical application and evidence of professional judgment.

Further Reading on ProQS

Preliminaries and General Items in Construction — where CDM-related costs (welfare, scaffolding, temporary works) sit in the cost plan.

Practical Completion and Defects Liability — how the H&S file requirement affects the PC certificate.

Risk Management Tools and Techniques — how H&S risk management fits within the broader project risk framework.

NRM 2: A Practical Measurement Guide — how CDM-related items are measured and specified in the BOQ.

Key References

HSE: CDM 2015 Overview — the HSE’s primary guidance page for CDM 2015, with links to duty holder-specific guidance.

HSE L153: Managing Health and Safety in Construction — the official approved code of practice for CDM 2015.

HSE: Designer Duties under CDM 2015 — specific guidance on the designer role, relevant to QS classification.

CDM 2015 Legislation (SI 2015/51) — the full statutory instrument for reference.