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We help civils and groundworks contractors turn plant and prelims from cost centres into profit drivers. YOUR BEST FRIEND IN BUSINESS

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23/10/2026

After a week on overhead recovery, here is the practical close. Five diagnostic signs that the model is behind the business.

If two or more of these are true, the model is out of date. If three or more, it is genuinely costing you money right now.

1. You cannot remember when the recovery rate was last changed.
If it has been more than 12 months, it is almost certainly wrong. Wages, insurance, and software all move every year, and usually up.

2. The same overhead uplift applies to every grade of labour.
Apprentices, semi-skilled, senior tradesmen all carrying the same recovery. That single blended figure is where mis-pricing sits on every mixed-grade job.

3. You have never compared theoretical to actual recovery.
If you cannot answer the question 'over the last twelve months, did we actually recover our overhead?' with a real number, you do not know. And it is usually a shortfall, not a surplus.

4. Chargeable hours in the pricing model do not match observed reality.
If the model assumes 1,700+ chargeable hours per tradesman and your tradesmen actually deliver 1,400 to 1,550, every unrecovered hour is unrecovered overhead. Multiply by every tradesman in the business, every year.

5. Margin has drifted down without an obvious reason.
Same team, same clients, same job mix, but margin two or three points lower than it was a few years ago. Almost certainly overhead recovery is not keeping pace with underlying cost inflation.

None of these are hard to fix once identified. All of them are quietly costing money until they are.

Comment RECOVERY below for the overhead recovery self-audit template we share with clients.

22/10/2026

A £3.6M general contractor in the Midlands came to us in autumn 2023. Broad job mix: some fit-out, some refurbishment, some new-build residential work under developers.

Their financial problem was familiar. Turnover held up year on year. Net margin had drifted from 9% to 5.8% over four years. Owner working harder, taking home less.

The instinct was to blame pricing. Pricing was not really the problem. Overhead recovery was.

What the initial review found:

A single overhead recovery percentage applied across all labour types.
The rate had been set in 2019 and never touched.
The model assumed 1,720 chargeable hours per tradesman per year. Actual delivered chargeable hours across the previous two years averaged 1,485.
Apprentices were being priced at the same recovery rate as senior tradesmen. On the roughly 22% apprentice content across the workforce, that meant genuine mis-pricing on almost every job.
No test had ever been done comparing theoretical recovery to actual overhead incurred. The gap, once calculated, was 26%.

What we rebuilt over 4 months:

1. Fully-loaded cost per grade, calculated for each of the 5 tradesman grades in the business
2. Chargeable hours reset to a realistic 1,510 hours per tradesman per year, with a stretch target above
3. Overhead recovery calculated per grade, refreshed against current annual overhead of £468K
4. New charge-out rates set for each grade, averaging a 12% uplift across the mix
5. Quarterly review process installed to test actual vs theoretical recovery

12-month outcome:

Turnover: £3.7M (broadly flat)
Net margin: 5.8% to 11.1%
Annual margin uplift: roughly £195K
Zero clients lost to the price increases

Director's reflection: 'We had assumed we needed more work to make more money. It turned out we needed the same work at the right price.'

The interesting number is not the £195K. It is the fact that this business had been fundamentally underpriced for four years, and nobody, internal or external, had ever run the numbers to see it. Overhead recovery is boring. Boring is often where the money is.

21/10/2026

If Monday's post named the leaks, this is what the fix looks like. Four principles that consistently move overhead recovery from theoretical to actual.

1. Fully-loaded costing per grade
Every grade of labour has its own fully-loaded cost. Base wage, employer NI, pension, holiday accrual, sick pay allowance, training, tooling, insurance load, and allocated supervision. Calculated grade by grade, not blended.
The blended average is where the biggest hidden losses sit.

2. Realistic chargeable hours
Actual, measured chargeable hours per tradesman. Not the theoretical maximum. Track it for a quarter and you will see the honest number. Most firms are 10 to 20% below what the pricing model assumes.

3. Annual refresh, not one-time set
Overhead moves every year. Insurance, rent, salaries, software. If the recovery number has not been refreshed in the last twelve months, it is out of date. This is a scheduled review, not a project.

4. Test recovery vs plan, quarterly
At the end of each quarter, calculate the total overhead you recovered through the labour rates you charged, against the total overhead you actually incurred. The gap tells you exactly where the pricing is behind. Well-run firms track this quarterly, adjust rates within the year, and enter the next quarter better calibrated.

Together, these four principles typically add 2 to 4 points of net margin on labour-heavy work. Same team. Same clients. Different maths.

Send us a message for the overhead recovery framework we use with clients.

20/10/2026

Honest question for the construction owners reading 👇

How does your business currently handle overhead recovery?

🅰️ Fixed percentage on top of labour cost, set years ago
🅱️ Per-hour uplift on chargeable hours, reviewed occasionally
🅲️ Grade-differentiated rates, updated annually
🅳️ Fully-loaded costing model, tested against actual recovery each year

Each answer says something specific.

A is where the largest firms in this sub-sector often sit. Comfortable, familiar, and leaking 3 to 5 points of margin.

B is the most common answer. Better than A, but the 'reviewed occasionally' tends to mean 'when the accountant asks about it at year-end'.

C is where well-run firms sit. Grade differentiation alone is worth 1 to 2 points of margin on labour-heavy work.

D is where a small number of very well-run firms sit. It is not more complicated. It is just done properly.

A, B, C or D in the comments.

19/10/2026

The standard construction overhead recovery calculation goes something like this: 'Take annual overhead, divide by expected chargeable hours, add it to labour rates as a percentage or a per-hour uplift.'

It is not exactly wrong. It is just wrong in ways that quietly cost most firms 2 to 5 points of net margin every year.

Here is what actually goes wrong with the standard model.

1. Overhead is estimated once and then forgotten.
The calculation was set two, three, sometimes five years ago. Since then, insurance has gone up. Software subscriptions have gone up. Rent has gone up. Wages of office staff have gone up. National Insurance has gone up. The recovery number has not moved.

2. Chargeable hours are optimistic.
The model assumes a tradesman is on chargeable work for, say, 1,700 hours a year. In reality, once you subtract training, sickness, weather days, travel between sites, and the days on jobs that never got billed, most firms are recovering across 1,400 to 1,550 hours per tradesman. If you priced on 1,700, every hour under that is lost overhead.

3. All grades of labour carry the same recovery.
An apprentice, a semi-skilled operative, and a senior tradesman all sit on the same overhead uplift. Wrong. Different grades have different associated overheads (supervision, tooling, insurance load) and should carry different rates.

4. Recovery is calculated on cost, not on risk.
A high-risk job that pulls management time, requires more supervision, and drags month-end reporting should carry a higher overhead recovery than a low-risk job. Most models ignore this entirely.

5. It is never tested against actual recovery.
The theoretical recovery number and the actual recovery achieved over a year are usually different by 15 to 35%. Most firms never check. They just keep pricing on the theoretical number.

The result: quiet margin loss on almost every job, on almost every project type, cumulatively significant across a year.

Overhead recovery is not the most exciting topic in construction finance. It is where the second-largest quiet margin leak lives, after job costing itself.

Message us OVERHEAD for the overhead recovery review we run with clients.

16/10/2026

5 Common CIS Errors that Can Result in Significant Financial Losses: 🚨

1. Failure to Apply for Gross Status: £400K+ in Lost Revenue.
2. Inadequate Verification: Weeks of Unnecessary Conflict.
3. Delayed Monthly Returns: Penalties and Strained Relations with HMRC.
4. Incorrect VAT Treatment: Enquiry Risk and Lost Funds.
5. Failure to Reconcile CIS Suffered: Missed Credits.

Correcting these errors can improve cash flow by £30K-£150K within 12 months. 💸

Obtain the CIS Review Checklist: comment CISWINS below.

15/10/2026

A £2.8M subcontractor came to us in early 2024. Groundworks and civils, working mostly under main contractors. Profitable business. Permanently squeezed on cash.

Their previous accountant had them on net status. They had been on net status for eight years. Nobody had ever asked whether they should be on gross status.

We ran the review. They qualified. They had qualified for years.

The application went in. Approval came through in eleven weeks.

What the numbers looked like.

Before gross status:
20% of every qualifying subcontractor payment received was deducted at source. On roughly £2.8M of qualifying turnover, that meant approximately £560K a year going to HMRC at source, refunded or offset only after the Corporation Tax return had been filed.

Timing matters here. The average balance sitting in HMRC hands throughout the year was roughly £280K of the firm's working capital.

After gross status:
0% deducted at source. The Corporation Tax bill was still paid in due course, but the £280K of average working capital was now in the firm's bank account, not HMRC's.

The director had spent five of the previous eight years running an overdraft that averaged £200K to £250K, paying interest of roughly £11K a year on it. Almost exactly the amount of working capital the gross status change freed up.

Additional gains from the same review:

The firm was also in a permanent VAT repayment position due to reverse charge VAT. Moving from quarterly to monthly VAT returns brought their VAT refund cycle from 90 days to 30 days, releasing a further approximately £45K of average working capital.

Total working capital freed by the CIS and VAT review: approximately £325K.

Director's reflection: 'I had been running that overdraft for eight years, paying interest every month, and the money was actually in HMRC's account the whole time. Nobody had ever told me it did not have to be.'

The mistake was not the previous accountant's. The compliance had been done properly. The gap was that nobody had ever treated CIS as a cash-control decision. Once framed that way, the answer was obvious.

This is Step 1 of the Smart CFO Framework: Cash Control.

Reminder: gross status requires meeting specific turnover, business, and compliance tests, and applications can be refused. This case is specific and does not automatically translate to any other firm. Any specific CIS decision needs current professional input.

14/10/2026

CIS looks like paperwork. Underneath, it is four operational disciplines that either work in your favour or against you every month.

Here are the four.

1. Verification discipline
Every subcontractor verified before the first payment. Verifications kept current. Records held. Sloppy verification is what pushes a subcontractor to the higher deduction rate, and the subcontractor almost always finds out later. Well-run firms verify as a routine, not as a fire-fight.

2. Monthly return timeliness
Filed on time, every month, without exception. Late returns generate penalties that compound. Missed returns damage HMRC standing, which can affect gross status renewal down the line. The rhythm is cheap. The consequences of missing it are not.

3. Deduction accuracy
Right rate for the right subcontractor. Tracked in the accounts as a separate control account, not buried inside overheads or cost of sales. Reconciled monthly. Poor accuracy leads to reconciliation nightmares at year-end and disputed subcontractor payments in between.

4. CIS suffered reconciliation
For subcontractors on net status, CIS suffered is a credit against your Corporation Tax bill. Not tracking it accurately means either losing the offset, or overpaying tax and having to reclaim. Both are wasteful. Well-run firms know their CIS suffered position monthly, not annually.

None of these are hard in isolation. Together they represent the difference between CIS being a cash-flow tool and CIS being a compliance drag that quietly costs money.

This is Step 1 of the Smart CFO Framework: Cash Control.

Reminder: general framework, not personal or tax advice. Specific CIS decisions need current professional input.

Send us a message for the CIS discipline framework we run with clients.

13/10/2026

Honest question for the construction owners reading 👇

Which CIS-related pressure is costing you most cash right now?

🅰️ Gross status delays or rejections
🅱️ Verification errors pushing subbies to the higher deduction rate
🅲️ Monthly return admin burden
🅳️ Reverse charge VAT creating permanent repayment positions

Most firms deal with all four at some point. What matters is which one is biggest for you today.

A is fixable, though slower than owners want. If you qualify and have not applied, the change is worth pursuing.

B is fixable this week. Verification hygiene is a daily discipline, not a project.

C is often less painful than it appears. The right rhythm and the right tools reduce the burden significantly.

D is a cash-timing question, not a cost question. Moving from quarterly to monthly returns changes the shape of the cash flow, if you are eligible.

A, B, C or D in the comments.

This is Step 1 of the Smart CFO Framework: Cash Control.

12/10/2026

Most construction owners view CIS as tax admin. That framing misses what CIS actually does.

CIS is not primarily a compliance regime. It is a cash-control mechanism that moves large amounts of money in and out of your bank account every month, on rules you can partially influence.

Here is what CIS actually does to your cash.

For subcontractors on net status:
20% of every qualifying payment is deducted at source. On a £2M turnover subcontractor, that is £400K permanently in HMRC hands over the course of a year, credited against Corporation Tax at year-end. Meaningful working capital drag every month.

For subcontractors on gross status:
0% deducted at source. The full amount flows through to your bank account when the customer pays. Corporation Tax still gets paid in due course, but the timing profile is completely different.

For contractors paying subcontractors:
Verification quality determines the deduction rate applied. Missing or expired verifications push a subcontractor from 20% to the higher deduction rate, damaging their cash flow and, indirectly, your relationship with them.

For any firm affected by reverse charge VAT (introduced March 2021 for B2B construction services in CIS scope):
The customer accounts for the VAT rather than the supplier. Meanwhile, VAT is still paid on materials, subcontractors outside scope, and overhead. The result: many affected firms move from being VAT-payers to being in a permanent VAT-recoverable position, with cash held by HMRC until the next return cycle.

The two cash levers most owners under-use:

1. Gross status for eligible subcontractors. If you qualify but have never applied, the difference in cash profile is transformational.

2. Monthly VAT returns instead of quarterly, for firms sitting in a permanent repayment position. Refunds every 30 days rather than every 90 days.

Neither of these is a tax dodge. Both are legitimate features of the system that most owners either do not know about or have never bothered to action.

This is Step 1 of the Smart CFO Framework: Cash Control. Getting the cash mechanics of CIS right is one of the highest-impact things a subcontractor can do to fund growth without borrowing.

Reminder: general framework, not personal or tax advice. Any specific CIS or VAT decision needs current professional input.

Message us CISFLOW for the CIS cash-control review we run with clients.

Address

206, New Road, Croxley Green
London
WD33HH

Opening Hours

Monday	9am - 6pm
Tuesday	9am - 6pm
Wednesday	9am - 6pm
Thursday	9am - 6pm
Friday	9am - 6pm

Telephone

+441923332586

Website

http://www.isaconsortium.co.uk/

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