Pre-Construction Information (PCI) Under CDM 2015 — A Trade's Guide (2026)

What is Pre-Construction Information?

Pre-Construction Information is the health and safety information about a project and the site where it will be carried out, gathered together and shared so that designers and contractors can plan and work safely. It is the "what you need to know before you start" pack for a construction project.

The whole point of PCI is to pass relevant information down the chain. The client knows things about the building and the site — its history, its surveys, its quirks — that a designer or a trade turning up on day one simply would not. CDM 2015 requires that knowledge to be written down and handed over, rather than locked in the client's head or buried in a filing cabinet, so that risks can be designed out, planned for or managed rather than stumbled upon.

The legal basis under CDM 2015

Under CDM 2015, the duty to provide Pre-Construction Information rests squarely with the client. Regulation 4 requires the client to provide PCI as soon as is practicable to every designer and contractor appointed, or being considered for appointment, on the project. This is not optional and it is not something a trade can be expected to invent for themselves.

Where there is more than one contractor (which is most projects beyond the very smallest), the client must appoint a Principal Designer and a Principal Contractor. The Principal Designer assists the client in pulling the PCI together — identifying what information is needed, gathering it and making sure it gets to the right people in a usable form. The client remains legally responsible for it, but in practice the Principal Designer does much of the legwork.

This is general guidance, not legal advice. The definitive source is the regulations themselves and the HSE guidance document L153, "Managing health and safety in construction". If you are unsure of your duties on a specific project, take competent advice.

What PCI should contain

There is no single fixed template, because the right content depends on the project. But CDM 2015 and the supporting HSE guidance set out the categories of information that good PCI covers. In broad terms, PCI should pull together:

• Project description and programme: what the works are, where, the key dates, and the time set aside for planning and construction.
• Client's duties and considerations: the client's requirements, including any rules they impose, and details of the management arrangements for the project.
• Planning and management arrangements: how health and safety is to be organised, communicated and monitored across the team.
• Existing site information: surveys, existing drawings, the asbestos register and any asbestos survey, ground conditions and contamination reports, the location of existing services (gas, water, electricity, drainage, telecoms), and structural information about the building.
• Significant design and construction hazards: the things that genuinely matter on this job — work at height, fragile materials, confined spaces, structural instability, traffic management and so on — not a generic list of every possible risk.
• Information for the next stages: material that will feed the Construction Phase Plan and, ultimately, the health and safety file for the finished structure.

A scrolling list of standard hazards that apply to every site is not useful PCI. The value is in the project-specific detail: the asbestos in the soffits, the live cable across the yard, the weak floor in the back room. That is the information that stops people getting hurt.

The golden thread: PCI, the Construction Phase Plan and the health & safety file

PCI does not exist in isolation. It is the first link in a chain of three CDM documents that run through the life of a project — sometimes called the "golden thread" of construction information. Understanding how they connect is the key to understanding PCI's purpose.

• PCI goes in: the client provides Pre-Construction Information before work starts, telling the team what is already known about the project and site.
• The Construction Phase Plan governs the work: the contractor (or Principal Contractor) uses the PCI to prepare a Construction Phase Plan (CPP) that sets out how the work will be carried out safely.
• The health & safety file comes out: information generated during the project that the building's owner or future occupiers need to maintain, alter or demolish it safely is compiled into the health and safety file at the end.

In short: PCI in, CPP during, H&S file out. Information flows from what was known at the start, through how the job was actually managed, to what the next person who works on the building will need to know. Each document feeds the next.

PCI versus the Construction Phase Plan — what's the difference?

These two are often confused, but they are distinct documents owned by different people at different stages.

Pre-Construction Information is provided by the client (assisted by the Principal Designer) before construction begins. It describes the project and the existing hazards — it is largely a statement of what is known.

The Construction Phase Plan is prepared by the contractor or Principal Contractor and sets out how the construction work itself will be managed and carried out safely. It is the response to the PCI: it takes the hazards identified in the PCI and explains the controls, sequencing, site rules, welfare arrangements and emergency procedures that will keep people safe during the build.

Put simply, PCI tells you what the problems are; the Construction Phase Plan says what you are going to do about them. A CPP is required for every construction project, including single-contractor and domestic jobs — even a sole trader doing a small build needs one, in proportion to the work.

Who is responsible at each stage?

CDM 2015 assigns clear duties, and it helps to know which hat you are wearing on any given job:

• Client: must provide PCI to every designer and contractor. The client carries the legal duty even where others help compile it. On domestic projects the client's duties usually pass to the contractor or Principal Contractor.
• Principal Designer: assists the client in identifying, gathering and passing on the PCI, and plans, manages and monitors the pre-construction phase.
• Designers: must take account of the PCI in their design work and provide information about residual risks that cannot be designed out.
• Principal Contractor: uses the PCI to plan, manage and monitor the construction phase and to draw up the Construction Phase Plan.
• Contractors (including individual trades): must take account of the PCI and the Construction Phase Plan, and feed back any new hazards they discover on site.

Proportionality — small jobs need far less

CDM 2015 is explicitly proportionate. The amount of PCI required scales with the size, complexity and risk of the project. A multi-storey commercial refurbishment with asbestos, deep excavations and a tight city-centre programme needs detailed, structured PCI. A small domestic job — replacing a kitchen, building a single-storey extension — needs far less.

For a small project, sensible PCI might be a short pack: a brief description of the works, the relevant existing drawings, an asbestos survey or register entry, the location of services, and a note of the obvious significant hazards. The aim is to give the trades what they actually need to plan and work safely — no more, no less. Padding a small job with reams of generic risk text helps nobody and tends to bury the one or two facts that genuinely matter.

What Pre-Construction Information should include

Use this checklist as a starting point, scaling each item up or down to suit the project. Not every project will need every row — but every row should be considered.

Practical tips for trades

Whether you are receiving PCI or compiling it, a few habits make the difference between a document that protects people and one that just ticks a box.

• Ask for it early. If you have been appointed and no PCI has appeared, request it in writing. You are entitled to it, and you need it to price and plan the work properly.
• Read it before you quote. Hidden asbestos, restricted access or buried services can blow a budget. PCI is where those costs first show up — factor them in rather than discovering them on site.
• Flag gaps. If the PCI is missing an asbestos survey or the location of services, say so. A "not known" that should be a "here it is" is a hazard in itself.
• Keep it proportionate when you compile it. If the client's duties have passed to you on a domestic job, give the next trade the facts that matter — not a generic template padded out to look thorough.
• Feed back what you find. Discover an unexpected hazard once work starts? Report it so the information chain stays accurate and the Construction Phase Plan can be updated.
• Hold on to it. Keep the PCI with your project records. It supports your Construction Phase Plan and, in the worst case, helps demonstrate that you planned the work on the basis of the information you were given.

The bottom line

Pre-Construction Information is the client's way of telling the team what they need to know to work safely — gathered with help from the Principal Designer and handed to every designer and contractor. It is the first document in the CDM golden thread: PCI in, Construction Phase Plan during, health and safety file out. Keep it proportionate, keep it project-specific, and use it to plan rather than filing it away unread. For trades, treating PCI as a real planning tool — not paperwork — is what keeps jobs safe, on budget and on the right side of CDM 2015.