Here’s the part nobody warns you about. The pressure doesn’t build in a neat, manageable line.
It accelerates.
And there’s a specific window where it hits hardest — businesses somewhere in the £20m to £200m revenue band, actively scaling, winning bigger clients, taking on more complex supply chains.
Big enough that sustainability now informs whether you win work.
Not yet big enough to justify the internal team it eventually demands.
That’s where the trap lives. And the businesses that get out of it fastest typically aren’t the ones that hire quickest — they’re the ones running a fractional sustainability function or working with an outsourced sustainability team that flexes with the business instead of locking them into a headcount that’s wrong within a year.
We call it the sustainability resourcing trap.
At any given moment, a business in this growth phase tends to have either too little sustainability resource or too much. Almost never the right amount.
How the gap opens as you scale
Below £20m, sustainability is often background noise. Clients mention it but rarely enforce it. You can get away with basic foundations to meet their lower standards.
Cross £20m and the commercial reality starts shifting.
You’re winning larger clients. Their procurement teams are more rigorous. The questions get specific: what’s your carbon footprint, what’s in your supply chain, where are your certifications, what’s your EcoVadis score? (EcoVadis is the supplier sustainability rating most large UK buyers use to grade the companies they buy from.) Increasingly, the answers decide whether you make the shortlist at all.
At this point there’s rarely anyone in the business who owns sustainability. When there is, it’s usually one person who shares it alongside a range of other responsibilities.
When businesses start to seriously consider a full-time ESG hire, it becomes a chicken-and-egg conversation. You can’t define the role properly until you know what good looks like, and you can’t know what good looks like until you’ve done it once at the right standard. So it sits in a gap — and the gap quietly costs you work you can’t always see you’ve lost.
The two ways it bites
If you’re growing organically, the requirements creep up on you. One big client asks for a Carbon Reduction Plan. Another wants EcoVadis. Then a public-sector tender lands with a chunk of the marks tied to social value and net zero. You bring someone in-house to cope, usually before there’s quite enough work to fill their time. A year later they’re overwhelmed, and you’re already behind on the next requirement before you can hire further resource.
If you’re growing by acquisition, it hits differently but just as hard. Every business you buy arrives with its own carbon data gaps, its own reporting obligations, its own half-finished sustainability work. One stretched person goes to overwhelmed overnight, and the integration plan rarely had a line item for any of it.
Either way you land in the same place.
Too little resource when the work spikes. Too much when it quietens.
And a nagging sense that you’re paying for in-house staff that will need to bring in consultants to do the technical work anyway.
What it actually costs you
This isn’t just a utilisation problem. It shows up in the sales pipeline.
Bids you should win, lost on the sustainability section. Contracts you’ve held for years, suddenly exposed because a more credible competitor got ahead. Marks left on the table in tenders because your sustainability story isn’t joined up enough to score well.
Take Rhodar — a demolition and remediation specialist supplying NHS trusts, government departments and the nuclear sector. As the contracts got bigger, carbon scoring moved to 10–15% of quality marks on tenders. The bid team couldn’t answer the questions. Not because Rhodar wasn’t credible, but because the sustainability infrastructure to back up the answers hadn’t been built yet.
We came in as the sustainability function, while they didn’t have one. Built the baseline, the reduction strategy, the bid tools, answered live tenders while the infrastructure took shape. Over 24 months we also helped them define what the in-house sustainability role should actually look like — skills, scope, what handing it over would mean. By the time they hired Lizzy, their first Sustainability Officer, the function was already running. We’re mentoring her through the transition now. The goal from the start was to make ourselves unnecessary. [Read their story →]
Supplying the NHS means publishing a Carbon Reduction Plan in a set government format under PPN 006, and since 2024 that applies to effectively all new NHS procurement, not just the large contracts. On central government work, social value — which explicitly includes climate — typically carries at least 10% of the available marks. So a weak sustainability answer doesn’t cost you a point here or there. You’re handing a tenth of the scorecard to a competitor before the rest of your bid has been read.
And none of this is a failing on your part. The goalposts are moving faster than any scaling business can comfortably staff for.
Why hiring faster isn’t the answer
The instinct is to fix a resourcing gap by hiring. It’s the obvious move and usually the wrong one at this stage.
An ESG hire typically solves the problem for about six months. You appoint a sustainability manager, the immediate fire goes out, and then one of two things happens. Either the work outgrows them and you’re back where you started. Or the work quietens and you’re carrying a salary that’s hard to justify to the board. You’re also asking one mid-level hire to be expert across carbon accounting, EcoVadis, certifications, supply-chain data and procurement standards — which is three or four jobs wearing one lanyard.
This is especially sharp for businesses in the £20m-£100m band. You don’t have the budget for a senior sustainability director. You don’t have the volume to keep a junior one fully productive. The market for mid-level sustainability professionals is thin and they’re expensive. And by the time you’ve got them through a three-month notice period, the tender you needed them for has closed.
The businesses that handle this well aren’t the ones that hire fastest.
They’re the ones that find a smarter way to flex.
A fractional sustainability function that flexes with you
The alternative is to treat sustainability resource as something that grows with the business, rather than a fixed headcount you keep guessing wrong. That’s the model behind a fractional sustainability function — an outsourced sustainability team that keeps the full range of capability available without the full-time cost or the wrong-sized hire.
That’s what we built Litmus to be.
We keep the full range in-house: carbon footprinting, reduction planning, EcoVadis, B Corp, ISO standards, ESG strategy, sustainable procurement and supply-chain reporting. So whatever your clients are asking for this quarter, we can meet it.
When you win a bigger client, move into a new market, or buy another business, the resource scales with you instead of needing a recruitment round and a three-month notice period.
Every engagement starts the same way. A clear read on where you are now, what’s being asked of you today, and what’s coming down the road as you scale. From there we work as an extension of your team — filling the gaps, leading on the complex pieces, making sure sustainability never becomes the thing that holds your growth back.
You decide how the relationship runs.
Some businesses want us in the background as a trusted partner, handling the heavy lifting while their team stays focused elsewhere.
Others want to build capability in-house over time, with us transferring the knowledge and stepping back as their own people grow into it.
We’ve done both.
We mentored a graduate into a new sustainability role at a Manchester textiles manufacturer, and we ran the fractional sustainability function for a £70m construction business while helping them recruit their permanent hire.
We’ll never push you towards the model that suits us instead of the one that suits where your business is heading.
Get ahead of it
The businesses winning the most competitive work right now share one habit.
They didn’t wait for sustainability to become a problem before dealing with it. They got ahead of it while it was still a choice — and it made them credible, compliant and genuinely competitive on the things their buyers now score.
If you want an honest read on where you stand and what the smart next move looks like, watch the short video on this page, then book a free 20-minute strategy session.
We’ll look at what you’re being asked for today, what’s likely coming next, and how to stay ahead of both. No jargon. No hard sell. Just a straight conversation about where you are and where you need to be.
