How to Manage Subcontractors: A System for Builders
The short answer
Manage subcontractors with a bank of two or three per trade, a written scope and rates before every job, bookings made from your programme, a daily photo report, signed variations, a score after every job, and payment on time, every time.
- Two or three subbies per trade. One electrician is a single point of failure, not a supply chain.
- Nothing starts without paper. Scope, drawings, rates, payment terms, start and finish dates and quality standard agreed in writing.
- Variations only on a signed form, from the subbie to you and from you to the client. Otherwise you pay for extras you cannot bill.
- Pay on time, every time. The best subbies choose who they work for. Verify them for CIS before the first payment.
Once you run more than one job, your margin is in your subcontractors' hands. They decide whether the programme holds, whether the finish is right first time and whether your client stays happy. Most builders still manage them by phone, from memory, with a price agreed on the doorstep.
This is the system Sviat uses at Craftex and teaches owners. Build a bank, put everything on paper and book from the programme. Then check the work, score it and pay on time. Want it set up in your company? Book a free strategy call.
Build a subcontractor bank, not a contact list
If one electrician lets you down and the whole programme stops, you do not have a supply chain. You have a single point of failure.
- Aim for two or three reliable subbies per trade. Electrics, plumbing, plastering, decorating, tiling, joinery, groundworks: whatever you use most.
- Keep one sheet: name, trade, day rate or typical rates, area covered, insurance expiry, CIS status, last job score.
- Try new subbies on small jobs before you trust them with a £100K extension.
- Ask your best subbies who they rate. Good trades know other good trades.
New trades to add? See how to find reliable subcontractors and vet them. Short of people right now? See how to find good tradesmen to hire.
Put everything on paper before the job
Every argument at the end of a job started with something that was never written down. Before a subbie starts, agree in writing:
| Item | Why it matters |
|---|---|
| Scope and drawings | They price the real job, not a guess. No "I thought that was extra" |
| Price or rates | Lump sum, day rate or measured rate, with what is included |
| Who supplies materials | Avoids double orders and missing items |
| Start and finish dates | Ties them to your programme |
| Quality standard | What "done" looks like, with photos of a finished example |
| Payment terms | How they apply, when you pay, any retention |
| Variations | Only on a signed form, priced before the work |
| Insurance | Public liability in date, copy on file |
| Non-solicitation | They do not approach your client directly |
Clear scopes and drawings let them price without calling you. A one-page subcontract order covers most small jobs. Have a solicitor check your template once, then use it every time. For the client-poaching risk, see non-solicitation agreements in construction.
Agreeing a price on site and "sorting the paperwork later". Later never comes, and the final account becomes a negotiation you lose.
Book from the programme
Most no-shows are booking problems. The subbie was booked by phone three weeks ago, another contractor called yesterday with a bigger job, and your date slipped off their list.
- Book every trade from your programme, with dates in writing.
- Confirm a week before and again the day before, with the address, access and what must be ready.
- Tell them early when your dates move. If you waste their day, they will waste yours.
- Have a back-up for every critical trade. That is what the bank is for.
If a subbie does walk off, follow our first 24 hours plan. If one is running late and it is costing you, see what to do about subcontractor delays.
Want your subbie booking and payment system checked?
Book a free call and we'll go through it with you.
Check the work without standing over them
You do not need to be on site to know how a subbie is doing.
- Daily site report with photos in the job's WhatsApp group or app: what was done, what is next, any problems.
- Stage checks before you pay: first fix photographed before boarding, tiling set-out agreed before adhesive goes on.
- A snag list per trade before they leave site, signed off by your site lead.
- Same problem twice? Write the fix into the checklist and brief every subbie on it.
Variations: signed before the work, both ways
A variation the client asks for on site goes through you, not straight to the subbie. Price it, get the client's signature, then instruct the subbie in writing. A variation the subbie raises is priced and signed before they do it. Without that, you pay for extras you cannot bill.
Score them and pay them on time
After every job, score each subbie from 1 to 5:
- Quality Right first time, no call-backs.
- Speed Finished within their dates.
- Tidiness Left the site clean and safe.
- Communication Answered, reported, flagged problems early.
The best scores get the next job first. Pay on time, every time: the best subbies choose who they work for. The contractor who pays on the day gets their best people.
If you are a CIS contractor, verify every subcontractor with HMRC before the first payment and deduct at the rate HMRC gives you. Check, too, that they should not really be your employee: our guide to employing or subcontracting labour explains the test.
When it works
Adam and Ali grew their building company by subcontracting the delivery of their £49K and £12K jobs. They also hired two full-time multi-trades, while Adam moved to sales. Subcontracting works when the system around it does.
Adam & Ali: delivery subcontracted, owner moved to sales
£91,796 signed in 8 days. Individual results, not typical or guaranteed.
Help building your supply chain
Sviat Jay runs Craftex, a London design and build company that delivers its projects through a supply chain of trades, and mentors owners one-to-one himself. Some owners are strong on site and weak on paper; others have the paperwork but no bench of trades. He works on your weak spot first.
The flagship is one-to-one, by application; smaller firms start in small groups (max 10–20) with regular one-to-ones. Built for results in about 4 months, not a 1–3-year program. The Construction Business Scorecard shows in 4 minutes where your business is most exposed, or book a free strategy call.
Ready to run your trades with a system?
Book your business assessment.
Subcontractors: this week
- List your subbies per trade and mark where you only have one
- Write a one-page subcontract order template with scope, dates and payment terms
- Confirm next fortnight's bookings in writing
- Score every subbie on your last finished job
- Check CIS verification and insurance dates for everyone on site
