Pre-construction information is the information already in the client's possession, or reasonably obtainable, about the project and the site, provided to every designer and contractor so they can plan and price the work knowing what they are walking into.
It is the first document in the CDM sequence and the one whose absence does the most damage, because everything downstream — designs, the construction phase plan, every RAMS — is built on assumptions that the pack exists to replace with facts.
Who provides it
The client. CDM 2015 regulation 4 requires the client to provide pre-construction information as soon as is practicable to every designer and contractor appointed, or being considered for appointment. Where a principal designer is appointed, they assist the client in identifying, obtaining and collating it, and in providing it to the right people at the right time.
The principal contractor then passes the relevant parts down to each contractor. On a domestic project, the client duties — including this one — transfer to the contractor or principal contractor, which in practice means the contractor has to find the information itself.
The duty holder map is set out in full in CDM 2015 explained, and the distinction between providing information and writing documents matters here: the client provides, the contractor assesses.
What it must contain
Regulation 4(4) requires information that is relevant, in an appropriate form, and proportionate to the risks. Appendix 2 of L153 gives the expected structure.
The project
Description, programme, key dates, the client's own arrangements for managing the work, the extent of the client's control over the site, and the identity of the duty holders.
The client's rules and constraints
Site rules, permit regimes, restricted access or hours, security arrangements, the interface with continuing occupation or operations, and any restrictions on deliveries, noise or dust. On a live hospital, school or retail site this section is the difference between a plan that works and one that is rejected on day one.
Existing environment and structures
Surveys and their dates, ground conditions and contamination, existing structures and their stability, previous structural alterations, load-bearing information, and neighbouring land uses. For a refurbishment, the asbestos survey — refurbishment and demolition survey, not a management survey — is the single most important item in the entire pack.
Services
Buried and overhead services, live systems, isolation arrangements, and drawings with their date and provenance. Also fire-fighting provisions and any high-voltage or high-pressure assets.
Significant design and construction hazards
Design assumptions and the sequences assumed, arrangements for coordination of ongoing design, residual risks the designers could not eliminate, and any temporary works implications.
The health and safety file
Where one exists from previous work on the structure, it should be provided — it is often the best available record of what is behind the finishes. See health and safety file requirements.
When it must arrive
As soon as practicable, and before the recipient needs it. That means designers get it before they design, contractors get it before they price and plan, and the principal contractor gets it in time to write the construction phase plan. Information arriving after a subcontractor has priced the work and mobilised is not compliance; it is a variation waiting to happen.
It is also not a one-off. As surveys are completed and design develops, the pack is updated and re-issued. A pre-construction information pack dated at tender stage and never revisited on a two-year project is out of date.
Using it properly as a contractor
- Read it before writing anything, and read the surveys rather than the summary of the surveys.
- Extract every item that affects your work into your hazard register — the asbestos register entries for the areas you will disturb, the service positions, the ground conditions, the occupier's rules.
- Reference it explicitly in your RAMS, with the document title and date, so a reviewer can see you used it.
- Identify what is missing and ask for it in writing, keeping the request and the reply.
- Re-check it when it is re-issued, and revise your documents if anything material has changed.
Step three is what turns the pack into evidence of a site-specific document. A RAMS that quotes the asbestos survey reference and the service drawing number is visibly written about this project — the distinction covered in generic versus site-specific RAMS. When the document is ready to check, uploading it for review will flag the mechanical gaps before a reviewer sees them.
When the pack never arrives
It happens, particularly on smaller commercial projects with inexperienced clients. The absence of information does not suspend your duty to plan the work safely, so:
- Request it in writing, specifically, naming what you need rather than asking for "the PCI".
- Escalate to the principal contractor, who has a coordination duty and their own interest in the answer.
- Commission or arrange what you cannot proceed safely without — a refurbishment and demolition asbestos survey being the obvious one — and price it as a variation.
- Where information is missing, treat the unknown as the worst reasonable case: services assumed live, materials assumed to contain asbestos until surveyed, ground assumed contaminated where history suggests it.
- Record your assumptions in the RAMS, so the basis of the assessment is visible if it turns out to be wrong.
The last point protects everybody. A document that states "no service drawings were provided; all services assumed live and located by CAT scan and trial hole prior to excavation" is a stronger document than one that quietly assumes there is nothing buried — and after an incident, the difference between the two is the difference between a defensible assessment and an indefensible one.
This article is general guidance on UK construction documentation practice. It is not legal advice, a compliance certification or a substitute for review by your own qualified health and safety personnel, who remain responsible for deciding whether any particular document is adequate. See our disclaimer.