Managing Subcontractors on a Small Site

How to manage subcontractors on a small site

Managing subcontractors well comes down to five things: vet them properly before they start, agree scope and price in writing, schedule them so they are not tripping over each other, snag their work before you pay, and pay fairly and on time. Get those right and good trades keep coming back.

On a small site you are the developer, the project manager and often the labourer too. Every subcontractor is a small bet: a brilliant plasterer turns a tired room into a sale, a bad one costs you a week and a redo. This guide walks the whole cycle, from finding trades to the final payment, with the UK rules you actually need.

Finding and vetting reliable trades

Vet a trade before money changes hands by checking three things: real recent references, valid insurance, and the right qualifications or cards for the work. A confident quote means nothing if the work behind it does not exist. Spend an hour up front and you save weeks later.

Start with referrals from builders you trust, then verify rather than assume. When you call a reference, ask specific questions: was it on time, on budget, and would you use them again. See a finished job in person if you can.

Run through this before you sign anyone up:

• References: at least two recent jobs you can actually contact, not a name on a flyer.
• Insurance: ask for proof of public liability cover (and employers' liability if they bring their own labour). Get the certificate, not a promise.
• Qualifications and cards: for the trade in question. A CSCS card shows site competence; gas work must be done by a Gas Safe registered engineer, and notifiable electrical work should be done by a registered competent person under Part P building regulations.
• VAT and CIS status: find out whether they are VAT registered and whether they are registered under the Construction Industry Scheme. This changes what you deduct and pay (more on that below).

If a trade dodges these questions or cannot produce paperwork, that is your answer. Reliable trades expect to be asked.

Agreeing scope and price clearly up front

Agree scope and price in writing before work starts. Most site disputes are not about dishonesty; they are about two people who each "knew" what was included and never wrote it down. A one page scope, a fixed price or a clear day rate, and an agreed payment trigger removes almost all of it.

Vague instructions create vague invoices. "Sort the bathroom" can mean a fresh coat of paint to you and a full re tile to them. For each trade, write down:

• The scope: what is being done, to what standard, and what is excluded.
• The price: fixed price for the package, or a day rate with an estimated number of days. State whether materials are included.
• Payment terms: when they get paid and what triggers it (for example, on completion and sign off of a defined stage).
• Variations: how extra work gets priced and agreed. Insist on a quick written note or message before any extra is done, never a surprise on the final bill.

Keep this somewhere both of you can see it. A scrap of paper in the van does not count. Tying scope, costs and a clear programme together is exactly why many small developers stop juggling spreadsheets; see spreadsheets vs property software for the trade offs.

CIS basics for paying subcontractors

If you pay subcontractors for construction work, you almost certainly need to operate the Construction Industry Scheme (CIS). Under CIS, you register as a contractor, verify each subcontractor with HMRC, deduct money from their labour payments, and pass it to HMRC as an advance payment towards their tax and National Insurance. This is rules, not advice; confirm your position with HMRC or an accountant.

According to GOV.UK, you must register as a contractor if you pay subcontractors for construction work, and CIS covers most building work including site preparation, alterations, repairs and decorating. The same guidance confirms the deductions count as advance payments towards the subcontractor's tax and National Insurance.

Before you pay a new subcontractor, you verify them with HMRC, who tell you the rate to use. The rates, per GOV.UK, are:

• 20% for registered subcontractors (the standard rate).
• 30% for subcontractors who are not registered or cannot be matched.
• 0% for those with "gross payment" status, where no deduction is made.

Two things small contractors get wrong. First, the deduction applies to labour, not materials, so keep the materials element clearly itemised. Second, the paperwork: GOV.UK states you must give each subcontractor a payment and deduction statement within 14 days of the end of each tax month. As their example puts it, for the tax month 6 May to 5 June, you must give the statement by 19 June.

Even on a one off refurb with two trades, this applies. Get registered, verify, deduct, report; it is far cheaper than an HMRC penalty.

Scheduling trades so they do not collide

Schedule trades in the order the build needs them and confirm the day before, so nobody arrives to a job they cannot start. On a small site there is no float; one trade turning up early to half finished first fix is a wasted day that still gets billed. A simple sequence on paper prevents most collisions.

The classic order is structure, then first fix (the pipes and cables that get buried), then plaster, then second fix, then decoration and floors. Each stage depends on the one before being finished and signed off, not just started. A plasterer cannot skim over half done electrics.

Build in a little buffer between trades and protect your lead time items (kitchens, windows, made to measure joinery) by ordering early. For the full sequencing logic and a sample programme you can copy, see scheduling a small build.

The single best habit is the day before call. A quick message confirming "you are on for tomorrow, the room is ready" saves the no show and the early arrival in equal measure.

Keep a project contact book

Keep one shared, up to date contact book for every trade, supplier and inspector on the job: name, trade, mobile, and a note on what they are doing and when they were last on site. When something goes wrong at 7am, you do not want to be scrolling three years of messages to find the roofer's number.

A good contact entry holds more than a phone number. Note their day rate or last quote, their CIS status, whether you have their insurance on file, and a line on how the last job went. Over a few projects this becomes your most valuable asset: a vetted list of people you would happily call again.

Keeping the contact book attached to the project itself, rather than in your head or across two phones, is one of the small workflow wins a tool like Build & Let is built around, so the trades, their costs and the snagging all live in one place.

Communicating expectations and snagging the work

Set expectations clearly and inspect work against them before you sign it off. "Looks fine" is not a standard. Walk the work, list every defect with its location and priority, share it with the trade, and only release final payment once the list is cleared. A defect caught before they leave is fixed in minutes; the same defect found after they are paid is a battle.

Treat snagging as a normal step, not an accusation. Most trades expect a snag list and would rather fix a few items now than get a bad reference later. Be specific: "hairline crack above the door to the landing, fill and repaint" beats "the plastering is rough."

A workable snagging routine:

1. Walk each completed stage with the trade or right after they finish.
2. Log every defect with its location, a photo, and a priority (high, medium, low).
3. Share the list and agree a date for the fixes.
4. Re inspect, then sign off and release the retained payment.

This is far easier when the list is structured and photographed rather than shouted across a room. Our construction snagging list guide covers how to run one properly, and the pre handover snagging inspection walks through the final check before a unit goes to sale or let.

Paying fairly and on time

Pay good trades fairly and on time, because reputation travels fast and reliable subcontractors choose who they work for. The cheapest quote is rarely the cheapest job once you count delays and redos. Pay the agreed price, on the agreed trigger, without making people chase you, and you move to the top of their list.

That does not mean paying for unfinished work. Tie payment to sign off: stage payments for longer jobs, a sensible retention until snags are cleared, and prompt settlement the moment the work passes. Within CIS, apply the correct deduction and hand over the statement, but do not use admin as an excuse to pay late.

Slow payers get the dregs: the trade fits you in around better clients, sends an apprentice, or simply stops answering. On a small operation where the same five trades carry your whole programme, being known as someone who pays properly is a genuine competitive edge.

Subcontractor checklist

Use this as a one page checklist for every trade you bring onto the site, from first contact to final payment.

Frequently asked questions

Do I need to register for CIS for a small refurb?

If you pay subcontractors for construction work, you generally must register as a CIS contractor, even on a small job. According to GOV.UK, CIS covers most building work including alterations, repairs and decorating. Check your exact position with HMRC or an accountant, as some situations differ.

What is the CIS deduction rate?

GOV.UK sets the standard rate at 20% for registered subcontractors and 30% for those who are not registered or cannot be verified. Subcontractors with gross payment status are paid with no deduction. The deduction applies to labour, not materials.

How do I check a tradesperson is qualified?

Ask for proof, do not assume. Check a CSCS card for general site competence, confirm gas work is done by a Gas Safe registered engineer, and ensure notifiable electrical work meets Part P via a registered competent person. Always get insurance certificates and two recent, contactable references.

When should I pay a subcontractor?

Pay on the agreed trigger, normally completion and sign off of a defined stage, after you have snagged the work. Hold a sensible retention until defects are cleared, then settle promptly. Within CIS, apply the correct deduction and issue the payment and deduction statement within 14 days of the tax month end.

How do I avoid disputes with trades?

Most disputes come from unclear scope, not bad faith. Agree in writing what is included, what is excluded, the price, the payment trigger, and how variations are priced before work starts. Keep one shared record both of you can see, and confirm any extra work in writing before it is done.

Bringing it together

Good subcontractor management is not complicated, but it is relentless: vetting, scope, scheduling, snagging and payment, repeated for every trade on every job. Keeping all of it in one place, the contacts, the costs, the snag lists and the programme, is exactly what Build & Let is built for. Start your 14 day free trial and run your next small build without the admin tripping you up.