How We Calculate Your Growth Ceiling

• Picture heating a drafty building on a cold day. Your boiler adds a steady amount of heat every hour. The warmer the room gets, the faster heat leaks out through every gap and seam. Early on, the temperature jumps. Then each degree takes longer. Eventually you coast toward a line where heat in equals heat out. That line is your growth ceiling.

• Now translate that to your business. You keep “turning up the boiler”... More ads, more quotes, more routes, yet the room never gets as warm as it should. Why? Because loss scales with size. As you grow, more customers leave in absolute terms, more callbacks eat the calendar, and the same effort buys less net progress. You’re working harder for smaller gains and telling yourself it’s a pipeline problem, when it’s really a math problem.

• So you don’t need a bigger boiler, you need a clearer model. Operators stall not because they lack hustle, almost all operators are people who say "they're willing to put in the work". They stall because they don't know where to put in the work. The good news is that your business's growth ceiling is governed by a small set of numbers. Once you can see the numbers, you can learn to change them and "govern the heat balance" of your business.

Keep reading if you want to stop chasing the next job and start engineering your growth.

The Four Inputs To Keep Track Of

1. Current Customers (Active Sites) The number of customers currently on recurring service. In Coheara this maps to active sites (≥1 run in the last 90 days).

2. New Customers / Month Average net-new customers you add each month (e.g., new maintenance contracts or converted one-off clients).

3. Monthly Churn Rate (%) The percentage of your current customers that leave each month (cancellations, pauses past 90 days, or no longer serviced).

4. Average Revenue per Site (ARPS) Your average monthly revenue per recurring customer. When you turn off sandbox mode in the calculator, you enter this figure; everything else is computed.

You can play with all of these inputs in Coheara's calculator for free.

What To Calculate (and why it matters)

• Ceiling Customers
  The steady state where monthly wins and monthly losses balance. Above this line, growth feels flat unless you change your inputs.

• Ceiling MRR
  Your revenue at that steady state. It moves up when you lift average revenue per site or push the ceiling higher.

• Time to Ceiling
  How long it takes, from where you are today, to hit that ceiling where that growth begins to flatten. We report a practical “close enough” window rather than a theoretical exact hit due to how exponential decay works mathematically.

• Operational Signals
  Churn, callbacks, and evidence compliance (Critical Control Points (CCPs)) move this line faster than ad spend. Fewer leaks and clearer proof sent to your customers can lift retention; simple bundles or upsells can lift Average Revenue Per Site (ARPS).

The Math

• How your base moves each month: You can treat each month like this: your existing customer base shrinks by a small, steady percentage (your churn), then new contracts/customers are added on top. New contracts aren’t assumed to cancel in the same month they start. This mirrors how recurring service actually behaves.

• How to estimate your ceiling: If you keep adding customers at roughly the same pace and losing about the same percentage of your base, you approach a line where adds and losses are in balance. That line is your customer ceiling. Multiply that by your average revenue per site and you get your revenue ceiling.

• How Coheara estimates time to “close enough”: Because you move toward the ceiling a little faster when you’re far away and slower as you get close, the approach isn’t linear. We translate that curve into a practical timeline (e.g., ~12, ~20, or ~27 months in the example below) so you can plan interventions.

Worked Example (contract-based, Recurring)

Company: “RidgeLine Mechanical”

Inputs:

• Current Customers = 500

• New Customers/Month = 60

• Monthly Churn = 10% (50 customers lost each month)

• Average Revenue Per Site (ARPS) = $150

What happens:

• Month 1 ends with about 510 customers (you gain 60 customers, but lose 50).

• Month 2 ends with about 519 customers.

• Month 3 ends with about 527 customers.

The gains keep shrinking as you approach the balance point.

Where it plateaus:

• Customer ceiling: ~600 customers.

• Revenue ceiling: ~$90,000 MRR at $150/site.

• The time it takes to hit the growth ceiling: ~11–12 months (95% of the ceiling), ~20 months (98% of the ceiling), ~27 months (99% of the ceiling).

Interpretation:

• If RidgeLine keeps doing business the same way as it does today, its growth will stall a little under 600 customers / $90k MRR in about 12 months unless it changes one of the levers: add more customers on avg each month, lose fewer customers on avg each month, or make more money on avg per site.

Why this Math matters for contract-based operators

• You can’t out-sell high churn. Route density collapses faster than ad budgets can replenish it. Tight procedures, evidence at critical steps, and a clean callback loop reduce churn and push the ceiling up.

• Small ARPS lifts from simple bundles (for example, filters + coil clean + drain flush, seasonal checks, gasket programs, hood deep-cleans) compound faster than chasing new customers. Raising ARPS increases Ceiling MRR even if adds and churn don’t change.

• When you know these four inputs and how they interact, you regain control. Add a few more buckets, reduce the leak by a point or two, or charge a bit more per bucket—the waterline moves where you want it.

The Three Levers and Example Applications

1) Acquisition — Get more customers per month

• Referral triggers in your proof emails: “Forward this report to your facilities peer for a free filter set.”

• Zone tagging to convert one-offs: Leave a QR code sticker on the asset you serviced with “Scan for next service.” that leads them to your booking page.

• Channel discipline: Double down on the 1–2 sources that reliably book recurring contracts (not just one-offs).

Outcome: Lifts your ceiling by pushing the balance point higher.

2) Retention — Keep customers longer; lower churn

• Capture photos on critical steps of your jobs and send it to the customer after the job is done, to build trust.

• Keep track of what jobs are callbacks so that you can trace your steps and retrain your team on where your SOPs are lacking and improve them.

• If a customer who's supposed to be recurring hasn't asked for your services figure out why and rescue those accounts before they become “inactive churn.”

Outcome: Small drops in churn create outsized gains in ceiling and stability.

3) Expansion — Make each customer more valuable over time

• Maintenance bundles: filters + coil clean + drain flush as a fixed monthly add-on.

• Seasonal upgrades: pre-heat checks, freezer gasket programs, hood deep-clean cycles.

• Site-tiering: bronze/silver/gold service levels tied to visit frequency and scope. You can also read this article for more ideas.

Outcome: Raises your revenue ceiling even if adds and churn don’t change.

Quick Examples Of How The Numbers Work:

Context we'll reference for the examples below:

• Current customers: 500

• Adds per month: 60

• Monthly churn: 10%

• ARPS: $150

1. Tiny retention win (–1 percentage point (pp) churn)
   New inputs: +60 adds, 9% churn.
   Outcome: Ceiling rises to roughly two-thirds of a thousand customers; revenue ceiling near $100k MRR. Same ad spend, higher ceiling.

2. Fix callbacks (–3 pp churn)
   New inputs: +60 adds, 7% churn.
   Outcome: Ceiling jumps materially (hundreds more customers); revenue ceiling adds ~$38k MRR vs. baseline.

3. More acquisition, same churn (+10 adds)
   New inputs: +70 adds, 10% churn.
   Outcome: Ceiling moves up by ~100 customers; revenue ceiling ~+$15k MRR vs. baseline.

4. Combo move (adds +10, churn –1 pp)
   New inputs: +70 adds, 9% churn.
   Outcome: Higher and faster—beats either lever alone.

5. Raise ARPS (+$20/site)
   New inputs: ARPS $170; adds and churn unchanged.
   Outcome: Ceiling customer count is similar, but revenue ceiling jumps ~+$12k MRR.

6. High churn hurts—fast
   New inputs: +40 adds, 20% churn, $150 ARPS.
   Outcome: Low ceiling and low revenue ceiling. You can’t out-sell that leak; work on retention first.

7. “Silent flatline” (adds drop to 0)
   New inputs: +0 adds.
   Outcome: You’re effectively at your ceiling already. Restart acquisition or reduce churn (reactivations/saves) to move again.

8. The 1-point churn rule of thumb (around 10% churn)
   New inputs: keep adds = 60; drop churn a point or two.
   Outcome: –1 pp roughly adds ~11% to the ceiling; –2 pp roughly adds ~25%. Small reductions matter a lot.

9. “Pilot → Standard” upsell (+$25 ARPS, –1 pp churn, +50 adds)
   Outcome: Moderate ARPS lift plus a small churn win outperforms discounting plays in revenue ceiling.

10. Route density flywheel (+5 adds, –1 pp churn, +$10 ARPS)
    Outcome: Tighter routes improve quality and throughput; all three levers nudge up together for a meaningfully higher revenue ceiling.

Two Questions You Should Review Quarterly

1. How far away is your next growth ceiling? (look at Time to Ceiling)

2. What one lever do you want to focus on improving the next couple months—new customers, less churn, or increasing average revenue per site (ARPS)?

Your contract-based service business can look unique on the surface—services, routes, gear, team, etc—but the growth engine inside obeys the same math. Treat it like a math problem, then use your operator instincts to move the parts.

How Coheara Computes This

We have a free calculator that calculates the growth ceiling for you.

• You provide average revenue per site.

• We read adds and churn from your activity (active vs. inactive/archived sites).

• We translate that into your customer ceiling, revenue ceiling, and a practical time-to-ceiling.

• Free plan: proof retained 30 days; Paid: 12 months. Deleted sites never inflate churn; inactive/archived inform it.

Next Steps

• See your live numbers → Make sites in Coheara for all your customers, have our AI draft a SOP for you, you edit the rest, have your techs run the procedure for your customers, then open your dashboard and see your next growth ceiling.

• Not on recurring yet? Read this article for ideas on how to turn your project-based business into a contract-based one.