Demand Controlled Ventilation Break-Even Revenue: $775K/Month

Fixed costs $50.5K/mo Year 1 base

Contribution margin 70% After variable costs

Break-even revenue $72.1K/mo Monthly target

Break-even timing Month 7 First positive month

Break-even calculator

Test monthly revenue, variable expenses, and fixed costs against break-even for a demand controlled ventilation systems business.

Lean Base Full

Monthly revenue Set this to monthly invoiced work and recurring service revenue. $ Low sales High sales Variable expenses Use direct costs that rise with each job, like materials, subcontract labor, commissions, and fuel. $ Low cost High cost

Money available to cover fixed costs $70,000 $100,000 revenue - $30,000 variable expenses

Margin ratio

70%

Covers fixed costs

Yes

Fixed monthly costs Use monthly overhead that stays in place even when job volume dips. $ Low overhead High overhead

Break-even chart Revenue Total costs

Which expenses are fixed, and which move with project volume?

Cost classification

Break-even is reliable only when materials, commissions, and fuel move with volume while lease, insurance, and core software stay fixed. If you treat inventory, overtime, or fuel like overhead, Month 7 break-even can look safer than it is.

Expense	Cost	Break-Even Treatment	Common Mistake
Hardware and CO2 Sensor Materials	Variable	Model at 18% of first-year revenue; on $1.196 million, that is about $215,000 per year.	Treating inventory as fixed overhead instead of tying it to booked installations.
Subcontracted Specialized Labor	Variable	Model at 7% of first-year revenue; it should rise as project work rises.	Locking subcontract labor into monthly overhead and understating margin risk.
Sales Commissions and Incentives	Variable	Model at 3% of first-year revenue because payouts follow closed sales.	Forgetting commissions in contribution margin and overstating break-even profit.
Vehicle Fuel and Consumables	Semi-variable	Use 2% of first-year revenue as the usage-linked portion, then review as route density changes.	Treating fuel like rent, even though service miles rise with active jobs.
Warehouse and Office Lease	Fixed	Use $6,500 per month across the relevant planning range.	Spreading lease dollars per job and making break-even look easier at low volume.
Insurance and Liability Coverage	Fixed	Use $1,800 per month unless coverage limits or fleet size change.	Scaling insurance directly with revenue without a policy trigger.
Building Management System Software Subscriptions	Fixed	Use $1,200 per month for core operating software.	Pushing the full software bill into job-level variable expense.
Fleet Maintenance Contract	Semi-fixed	Use $950 per month until fleet capacity changes, then step it up with added vehicles.	Modeling maintenance like fuel instead of a capacity step.

How does break-even change from lean to base to full operating scale for CO2-based ventilation systems?

Scenario table

As maintenance agreements climb from 30% in Year 1 to 85% in Year 5, contribution margin improves from 70.0% to 74.6%. But payroll scales faster too, so the fixed-cost floor rises and break-even still moves up.

Planning assumptions only; actual break-even will move with close rate, labor mix, and project timing.

Scenario	Monthly Revenue	Variable Costs	Fixed Costs	CM Ratio	Operating Profit	Break-Even Signal
Lean opening year	$99.7k	$29.9k	$54.3k	70.0%	$15.5k	Break-even is about $77.6k, so the cushion is only about $22.1k.
Base Year 3 case	$271.0k	$74.8k	$73.8k	72.4%	$122.4k	Break-even is about $102.0k, leaving a solid $169.0k cushion.
Full Year 5 case	$476.9k	$121.2k	$110.5k	74.6%	$245.2k	Break-even is about $148.1k, and the $328.8k cushion is wide.

What pressures break-even for demand-controlled ventilation systems?

Stress test

The plan has a cushion, but it can shrink fast if commissioning slips, overtime creeps up, sensor substitutions rise, or service contracts don’t attach after installs. A small drop in bookings or a 1-point margin hit moves break-even fast.

Stress Case	Changed Assumption	Break-Even Revenue	Revenue Gap	Risk Signal
Current plan	No change.	$775k	$421k cushion	Year 1 revenue clears break-even, but the buffer is not wide.
Revenue shortfall	Bookings soften to $997k.	$775k	$222k cushion	A softer close rate leaves less room for delays.
Fixed-cost pressure	Year 2 fixed costs rise to $609k at 71.7% contribution margin.	$850k	$346k cushion	Overhead creep lifts the break-even bar even if sales hold.
Margin pressure	Margin slips 1 point on $997k revenue.	$785k	$212k cushion	One point of margin loss removes about $10k of contribution.
Combined pressure	Bookings soften to $997k, fixed costs rise to $609k, and margin slips 1 point.	$861k	$136k cushion	The buffer gets thin fast if installs slow and attach rates weaken.

Can this DCV business justify the lease, hires, and fleet spend before it signs the big check?

Founder checklist

Test demand, margin, and cash before the big spend. This model reaches break-even in Month 7, but the cash low lands in Month 6 at $619K, so don’t lock the lease, hires, or fleet until booked work and recurring service are real.

1Lease need$6.5K/mo

Verify booked installation demand can carry the $6.5K monthly warehouse and office lease before you sign, because fixed space only works when the pipeline is already there.

2Margin mix70% CM

Price hardware and sensor materials at 18% of Year 1 revenue, and keep total variable costs near a 70% contribution margin, so each install helps pay the overhead.

3Equipment timing$22K

Schedule the $22K diagnostic and calibration spend only against confirmed jobs, because equipment tied to a live backlog protects cash and keeps the startup from buying idle tools.

4Staffing ramp5 roles

Match the five Year 1 roles to booked installation hours before you add headcount, because the staffing ramp has to follow real work, not hoped-for volume.

5Cash floor$619K

Keep the $85K van and other capex inside the $619K Month 6 cash floor, because the model’s lowest cash point arrives before Month 7 break-even.

6Demand engine$45K / $2,500 CAC

Tie the $45K Year 1 marketing budget to the $2,500 CAC, and require maintenance agreements at every commissioning handoff so new installs turn into repeat service.