If you have ever compared two cleaning chemical bids and wondered why one supplier’s gallon price looks half what another charges, this is the guide that untangles it. Concentrate and ready-to-use (RTU) products are quoted in units that aren’t directly comparable, and the mistake of comparing them at face value costs facilities real money — in both directions.
This guide is for facility managers and procurement officers evaluating cleaning programs, negotiating bids, or trying to determine whether switching from RTU to concentrate (or vice versa) makes financial sense. It covers the math, the hidden costs on both sides, and a worked example you can adapt to your own site.
The Core Math
The only meaningful number is cost per ready-to-use gallon. Everything else is noise.
For concentrate:
[ \text{Cost per RTU gallon} = \frac{\text{Cost per concentrate gallon}}{\text{Dilution ratio} + 1} ]
A 1:64 dilution means 1 part concentrate to 64 parts water, producing 65 parts of working solution. So:
[ \frac{\$30.00}{65} \approx \$0.46 \text{ per RTU gallon} ]
A 1:128 dilution at the same concentrate price:
[ \frac{\$30.00}{129} \approx \$0.23 \text{ per RTU gallon} ]
For RTU: The cost per gallon is the shelf price. A $3.50/gallon RTU product is $3.50 per working gallon, full stop.
At those numbers, the concentrate wins by a factor of 7–15x on chemistry cost alone. But chemistry cost is not the whole story.
What the Concentrate Math Leaves Out
Concentrate programs have real costs that the per-gallon calculation ignores. Honest procurement means accounting for all of them.
Dispensing Equipment Capital Cost
Closed-loop wall-mount proportioners typically run $150–$400 per unit installed, depending on the system and number of chemical positions. In-line venturi systems (installed at a hose bib) are less expensive but less precise. Bottle-fill dispensing stations for multi-product programs can run $500–$1,200 per location, including installation.
These are one-time costs, but they get annualized in any real comparison. Over a five-year equipment life, a $300 proportioner = $60/year per station. If you have 12 stations in a large facility, that is $720/year in annualized equipment cost.
Dispensing equipment also requires maintenance. Proportioner tips and check valves need periodic replacement. Budget 10–15% of unit cost annually for maintenance parts and service.
Dilution Error Cost
This is the hidden cost that kills concentrate ROI in programs without adequate controls.
Over-dilution (too much water): The cleaner is now under-strength. Cleaning takes more passes, soils don’t release, and a frustrated crew either re-cleans or accepts substandard results. In a food processing environment, under-strength cleaner is a food safety issue.
Under-dilution (too much concentrate): The solution is over-strength. Chemistry cost increases, surface compatibility risks rise (some surfaces — vinyl tile, polished concrete, aluminum — are pH-sensitive), and residue buildup can become a problem. In regulated environments, residue of a cleaning chemical on food contact surfaces at elevated concentration is an audit finding.
Studies on manual dilution without proportioners show error rates of 30–60%. Operators guessing ounces-per-gallon frequently produce working solutions that are 50–200% of the intended concentration. Proportioners with fixed tips reduce this to near-zero for dilution ratio accuracy — which is the primary argument for the proportioner capex.
Labor Cost for Dilution
Manual dilution takes 2–5 minutes per bucket fill. In a facility where staff fill 10 buckets per shift across 3 shifts, that is 60–150 minutes of labor per day spent dispensing chemistry. At a fully-loaded labor rate of $22/hour, that is $22–$55 per day, or $8,000–$20,000 per year just for the labor of diluting chemicals.
Automated proportioners eliminate most of this. Push-button bottle fill systems are nearly instantaneous. This is a meaningful offset to the equipment capital cost.
Storage Volume
A 200,000 sq ft facility using 4 gallons of RTU neutral cleaner per day goes through approximately 1,460 gallons per year. That requires receiving, storing, and disposing of 1,460 one-gallon containers, or equivalent bulk packaging.
At a 1:64 dilution ratio, those same 1,460 RTU gallons come from 22.5 gallons of concentrate. The storage footprint difference is roughly 65x. In a facility where chemical storage space is limited or subject to fire code scrutiny (bulk flammable storage limits, etc.), the concentrate advantage in storage volume is significant.
Freight and Shipping Weight
RTU products are 90–99% water. You are paying to ship water across the country. Concentrate programs dramatically reduce shipping weight per equivalent volume of working solution. In freight-sensitive procurement (regional suppliers, LTL shipping, or locations with high fuel surcharges), this differential is material. Many distributors offer better freight terms on concentrate programs specifically because of the density advantage.
Packaging Waste
1,460 one-gallon containers per year versus 22.5 gallon jugs. The container disposal cost and environmental compliance burden differs by an order of magnitude. This is relevant for facilities with aggressive sustainability reporting or zero-waste commitments.
Where RTU Genuinely Makes Sense
The concentrate advantage evaporates in specific situations. RTU is the right choice when:
Very low volume applications. A single restroom in a 5,000 sq ft office building uses perhaps 2–3 gallons of cleaner per week. There is no ROI on a proportioner for that volume. Buy RTU.
Untrained or high-turnover crews with no proportioner. If there is no dispenser and staff are measuring manually, the dilution error risk with concentrate can exceed the cost savings. RTU is the safer choice when controls are absent.
Spot-use specialty chemistries. Stainless steel polish, leather conditioner, specialty glass cleaner for anti-glare coatings — some products are only available or only practical in RTU form, and usage volumes don’t justify dispensing infrastructure.
Regulated environments where dilution drift is a compliance risk. In a pharmaceutical manufacturing environment (FDA-regulated), some cleaning validation protocols require precisely formulated solutions that cannot tolerate field dilution variability. RTU or lab-prepared solutions may be required by the quality system.
Products with a short shelf life once diluted. Some chemistries (certain peracetic acid products, some hydrogen peroxide solutions) degrade quickly once diluted. RTU packaging preserves shelf life at the correct use concentration. Check product specs.
Dispensing System Options
| System Type | Capital Cost (approx.) | Dilution Accuracy | Best Fit |
|---|---|---|---|
| Closed-loop wall-mount proportioner | $150–$400/unit | ±5% when maintained | High-volume programs, 3+ products |
| In-line venturi (hose-end) | $30–$80/unit | ±10–15% | Single-product, high-water-volume uses (floor scrubbers) |
| Bottle-fill station (multi-position) | $500–$1,200/station | ±3% (metered) | Multi-product programs, large janitor closets |
| Manual measuring (graduate/cup) | $0 | ±30–60% | Last resort; not recommended for high-volume |
| Auto-scrubber on-board dosing | Varies (built-in) | Manufacturer spec | Floor scrubber programs |
Closed-loop systems — where the chemical container is a sealed unit that connects to the proportioner without open pouring — have additional safety advantages: no splash exposure during container changes, no label confusion, and tamper-evident accountability.
Worked Example: 200,000 Sq Ft Distribution Warehouse, Neutral Floor Cleaner
Scenario: A 200,000 sq ft class-A distribution center on a 24/7 operation. Floor care is the primary chemistry use. The facility uses ride-on auto-scrubbers; floor is sealed concrete. Neutral pH cleaner, used at approximately 4 gallons of working solution per 1,000 sq ft per scrubber pass, once daily across 100,000 sq ft (the remainder is racking, not mopped daily). That is 400 gallons RTU per day.
Annual volume: 400 gallons/day × 365 days = 146,000 RTU gallons per year.
Option A: RTU neutral cleaner at $3.20/gallon (bulk pallet pricing)
| Item | Annual Cost |
|---|---|
| Chemistry (146,000 gal × $3.20) | $467,200 |
| Storage (no additional requirement) | $0 |
| Labor for dispensing (auto-fill, negligible) | ~$500 |
| Freight (included in $3.20) | — |
| Proportioner capex | $0 |
| Total annual | ~$467,700 |
Option B: Concentrate at 1:64 dilution, $28.00/gallon
| Item | Annual Cost |
|---|---|
| Concentrate needed: 146,000 ÷ 65 = 2,246 gallons × $28 | $62,888 |
| Proportioner capex annualized: 8 auto-scrubber dosing units × $200 ÷ 5 yr | $320 |
| Proportioner maintenance (15% of $1,600 capex) | $240 |
| Labor for concentrate handling (slightly higher than RTU for container changes) | ~$1,200 |
| Freight savings (separate line, absorbed in concentrate price in this case) | — |
| Total annual | ~$64,648 |
Annual savings with concentrate: approximately $403,000. Even if these estimates are off by 30%, the concentrate program wins decisively at this volume.
This is not a cherry-picked example. Any facility using 100+ gallons of RTU cleaner per week on a commodity neutral cleaner should be on a concentrate program.
Dilution Error Costs in Both Directions
| Scenario | What Happens | Cost Impact |
|---|---|---|
| Under-dilution (too strong) | Over-use of concentrate; possible surface damage; residue issues | Chemistry cost 1.5–3× expected; potential service call |
| Over-dilution (too weak) | Cleaning effectiveness drops; re-cleaning required | Labor 1.2–2× expected; soil accumulation risk |
| Correct dilution, wrong product | Right ratio, wrong chemical for soil/surface | No direct cost; may cause damage or leave soil |
| No dilution (concentrate used neat) | Surface damage, safety hazard, chemistry waste | Unpredictable; may require remediation |
The cost of chronic over-dilution in a floor care program is not just chemistry waste — it means the floor isn’t getting clean. Soil buildup forces early strip-and-recoat cycles on finished floors, which can cost $0.25–$0.45 per square foot in labor and product. A 100,000 sq ft finished floor stripped one year early because of chronic under-strength cleaner = $25,000–$45,000.
Procurement: Comparing Suppliers Honestly
When one supplier quotes you concentrate and one quotes RTU, you cannot compare $/gallon. You must convert both to cost per RTU gallon, then build in total program cost.
Request from every supplier bidding concentrate:
- Confirmed dilution ratio with method (factory-set proportioner tip, titration test procedure, or pH reference)
- Recommended dispensing equipment, cost, and who supplies/maintains it
- Product technical data sheet with verified active ingredient concentrations
- SDS (GHS-compliant, current)
- Shelf life at concentrate and at working dilution
Request from every supplier bidding RTU:
- Price at multiple volume tiers (per case, pallet, truckload)
- Shelf life
- Freight terms and minimum order
- SDS
Build a side-by-side cost model at your actual usage volume. The template in the checklist at the end of this guide gives you the structure.
A supplier who refuses to give you a clear dilution ratio or who quotes a vague “use as needed” instruction for a concentrate is a red flag. You cannot manage chemistry cost or compliance without knowing the intended dilution.
Common Mistakes
1. Comparing concentrate $/gallon to RTU $/gallon directly. $28/gallon concentrate looks expensive next to $3.20/gallon RTU until you divide by 65. Always convert to cost per working gallon.
2. Not accounting for proportioner capex. A concentrate program without dispensing equipment is not a concentrate program — it is a manual-dilution problem waiting to happen. Budget for the dispensers.
3. Assuming staff will dilute correctly without controls. They won’t, consistently. Manual dilution variability is a documented problem. If you cannot install proportioners immediately, use pre-measured concentrate packets (available for many products) as an interim solution.
4. Ignoring freight on RTU. RTU products shipped LTL have significant freight cost built into the per-gallon price. Ask for freight-out pricing on high-volume RTU to see the true landed cost.
5. Not annualizing the cost comparison. A one-time proportioner installation of $2,400 looks expensive. Spread over five years = $480/year. Against $403,000 in annual chemistry savings at scale, it is trivial. Do the five-year model, not the line-item comparison.
6. Switching to concentrate mid-contract without re-reading compliance requirements. Some state-regulated facilities, pharmaceutical sites, or food processing operations have documentation requirements for cleaning solutions. Switching from a pre-validated RTU to a concentrate diluted on-site may require re-documentation or re-validation. Check before switching.
Printable: Cost-Comparison Worksheet
Fill in the yellow-highlighted fields with your site data. The math is done for you.
| Input | Your Site | Notes |
|---|---|---|
| Daily RTU usage (gallons) | _ | Measure from consumption records, not estimation |
| Annual RTU usage (gal/day × 365) | _ | |
| RTU Option | ||
| RTU price per gallon (bulk) | $_ | Get pallet-tier pricing |
| Annual RTU chemistry cost | $_ | Annual gal × $/gal |
| RTU freight cost (annual) | $_ | Confirm freight terms |
| RTU storage cost (if any) | $_ | |
| RTU Total Annual Cost | $_ | |
| Concentrate Option | ||
| Concentrate dilution ratio | 1:_ | Get in writing |
| Cost per RTU gallon (concentrate) | $_ | Conc. $/gal ÷ (ratio + 1) |
| Annual concentrate gallons needed | _ | Annual RTU gal ÷ (ratio + 1) |
| Annual concentrate chemistry cost | $_ | |
| Proportioner capex (annualized) | $_ | Total install ÷ 5 years |
| Proportioner maintenance (annual) | $_ | ~15% of capex/yr |
| Additional labor for concentrate handling | $_ | Estimate if different from RTU |
| Concentrate Total Annual Cost | $_ | |
| Annual Savings (RTU minus Concentrate) | $_ | |
| Payback on proportioner capex | _ months | Capex ÷ (monthly savings) |
See the companion guide Dilution Math: How to Calculate True Cost Per Use for the underlying math and a more detailed dilution ratio conversion table.