The Subcontract Chain

The main contractor needs accurate information about people it has no relationship with. The only mechanism available is the contract.

For teams turning the subcontract chain into a repeatable record, the original resource provides a useful operational reference for time, attendance and reporting workflows. It should be assessed alongside GOV.UK workplace guidance so the software choice remains grounded in site practice and applicable guidance.

How deep it goes

Main contractor, subcontractor, sub-subcontractor, labour-only gang, individual.

Four tiers is ordinary. On large projects five or six.

And the information the site needs — identity, competence, hours — originates at the bottom and has to travel up through every commercial interface on the way.

Each interface is a place it can stop.

What to require, and where

In the main subcontract: that every person presented for access is competent, has the right to work, and will be presented for induction before first access.

That the subcontractor imposes the same obligations on anyone it engages, which is the flow-down clause and is the only thing that reaches tier three.

That records are produced on request, within a stated period.

And that the site may refuse access to anybody whose evidence is not produced, which is the enforcement and has to be explicit or it becomes a negotiation at the gate.

Where it breaks

The flow-down clause exists and is not passed on, which nobody discovers until an incident.

A gang turns up with an extra person for the day.

A labour agency supplies somebody at short notice on a Friday and the paperwork follows on Monday, or does not.

And the tier where nobody is looking: typically three or four, where the commercial relationship is informal and the records are a WhatsApp message.

Verifying rather than trusting

Sample audits at the tier below your direct subcontractor, which is uncomfortable and is where the failures concentrate.

Ask a tier-one subcontractor to produce the evidence for a person engaged by their subcontractor. The time it takes is the measure of whether the flow-down is real.

And check whether the people on site match the people on the subcontractor's own records, which is a different question from whether they match yours.

The commercial reality

A subcontractor under price pressure and behind schedule will bring whoever is available.

Which is not dishonesty. It is the predictable result of a programme that moved and a penalty that did not.

Meaning the access controls have to hold under that pressure, because the pressure is constant and the goodwill is not.

A gate that admits an unverified person because the job is urgent has no function.

Agency and self-employed labour

Common in construction and frequently the largest group on site.

The agency holds the employment relationship, the subcontractor holds the work, and the site holds the risk.

Agree explicitly which party verifies competence and right to work, because all three will assume it was one of the others.

And note that self-employed status is a question with tax and employment consequences that sit outside this subject and are affected by how the site treats people — a matter for advice rather than assumption.

What the site actually needs from each tier

A list of people expected, before they arrive.

Competence status and expiry for each.

Confirmation of right-to-work verification, or the documents if the site does it.

And a named contact who can answer a question about a person at seven in the morning.

Four things. Everything else is the subcontractor's business.

The measure

People on site whose engaging company cannot be identified, which should be zero and rarely is.

Time from request to production of evidence, by subcontractor.

Access refusals by subcontractor, which identifies who is presenting unverified people.

And the depth of the chain, actually mapped, because most sites do not know how many tiers are present until somebody asks.

Making the requirement easy to meet

A subcontractor who cannot produce the evidence quickly is usually disorganised rather than obstructive.

Give them a format: a spreadsheet or a portal upload with the four fields, rather than a request to send certificates by email.

And accept the evidence once per person rather than per project, where the same companies work across several of your sites.

Most non-compliance in this area is friction rather than intent, and reducing the friction converts more of it than enforcement does.

The clause that is worth having

A right to refuse access, stated plainly, with no exception for urgency.

Because every negotiation about it happens at seven in the morning with a crane booked, and a clause that survives that conversation is one written to survive it.