Ceramic Coating Solids Content: What the Number Means

Ceramic coating solids content can be useful information, but a percentage is not a protection score. You first need to know whether it describes nonvolatile material by weight or by volume, and which method and conditions produced the result: ASTM treats those as different measurements. Neither number, on its own, tells you how many years a coating will protect your vehicle. See the public descriptions of ASTM D2369 for weight-based volatile content and ASTM D2697 for volume nonvolatile matter.

The useful question is not “Which bottle has the biggest percentage?” It is “What was measured, and does that measurement answer the question I am trying to solve?” That distinction lets you take technical information seriously without turning one laboratory number into a promise it was never designed to make.

What does coating solids content actually measure?

ASTM D2369 describes a method for determining the weight percentage of volatile content in coatings and says that weight-percent solids, also called nonvolatile matter, may be determined by difference. In plain language, this is a weight-based accounting of the tested material under specified conditions, not a measurement of scratch resistance, appearance, or service life. Read the method's scope and significance.

ASTM D2697 addresses another quantity: the volume of dry coating obtainable from a given volume of liquid coating. Its public description connects that value to comparing coverage at a specified dry-film thickness. That is a legitimate use for volume-solids information, but it is still a different question from how a particular coating performs on a particular vehicle. Read the volume-based method's purpose.

Start by writing the full name of the reported quantity. “Solids: 60%” leaves a blank where the basis belongs. “Nonvolatile content by weight, measured using the identified method” gives you something you can examine and compare, provided the remaining conditions also match.

If a seller uses “high solids” without a numerical value, treat it as a description to clarify, not a number you can insert into a calculation. Ask for the basis of the description and the practical benefit being claimed. Do not fill the gap with a percentage borrowed from a different product or an industry anecdote.

Weight percent and volume percent are not interchangeable

Weight and volume have different denominators. A mass divided by a mass is not the same measurement as a volume divided by a volume; the ASTM methods identify those separate bases explicitly. D2369 describes the weight basis, while D2697 describes the volume basis.

Consider two invented report summaries, used only to explain the arithmetic. They are not Undrdog specifications, application quantities, or instructions for conducting a test:

Hypothetical report	Calculation	What it says	What it does not say
A report identifies 40 g of nonvolatile material relative to a 100 g original sample.	40 ÷ 100 × 100 = 40%	40% on the stated weight basis.	Not 40 mL of dry coating per 100 mL of liquid.
A report identifies 60 mL of dry coating obtainable from 100 mL of liquid under its method.	60 ÷ 100 × 100 = 60%	60% on the stated volume basis.	Not a claim that 60% of what you dispense remains on your car.
Two product summaries say “60% by weight” and “40% by volume.”	No direct ranking from these two numbers alone.	The reporting bases differ.	Not proof that the larger printed number gives more dry-film volume or better protection.

The temptation is to read the percentages as points on one scoreboard. Resist it. Before comparing values, ask for a common basis and comparable test conditions; if those are unavailable, mark that part of the comparison “not established” rather than treating the larger figure as the winner.

Even a theoretical conversion deserves care. ASTM D2697 notes that measured dry-coating volume may differ from a prediction made by simply adding the raw ingredients' weights and volumes. Its public explanation includes volume contraction or expansion in resin solutions, which is a good reason not to improvise a conversion from a partial ingredient list. ASTM explains that limitation.

Test conditions belong next to the percentage

A method name matters because it defines the measurement being discussed. ASTM D2369 specifies controlled test conditions, acknowledges that it may not apply to all coating types, and identifies circumstances in which producers and users may agree to another procedure. That is not a license to select whichever result looks most impressive; it is a reason to ask what procedure was actually used and why it fits the material. The applicability limits are in the public scope.

For a useful technical comparison, request the exact product identity, reporting basis, method and version, sample preparation, and relevant conditions. Also ask whether the value is measured, calculated, or a stated target. Keep that distinction visible in your notes rather than presenting unlike kinds of information as equivalent laboratory results.

A listing for an ASTM method is not a test report for the bottle in front of you. The pages cited here describe measurement methods; they do not identify HCC or another named detailing product as having passed a test. D2369 and D2697 should therefore be read as method references, not product endorsements.

Do not turn this discussion into an evaporation experiment in a kitchen or garage. ASTM explicitly assigns responsibility for appropriate safety practices and regulatory considerations to the method's user. Its scope includes that safety limitation. Obtain suitable documentation or qualified testing instead of heating a coating to see what remains.

Does higher solids content mean a thicker installed coating?

Volume-solids information has a real relationship to dry-coating yield: ASTM D2697 says it measures dry volume obtainable from liquid volume and is useful when comparing coverage at a specified dry-film thickness. It does not report the thickness of a coating installed by a particular person on a particular car. That distinction follows the method's stated purpose.

To connect a bottle-level value to your installation, you would need a defined application, area, and a defensible account of what was deposited. Product dispensed and installed film are not interchangeable entries in a job record. Ask how the finished-film claim was established instead of multiplying bottle volume by a percentage and announcing a thickness.

Do not make the coating thicker, use extra layers, or change the leveling process just to improve an imagined number. Follow the exact product's installation directions and evaluate the completed work against that process. A buyer's comparison should not become an unofficial application recipe.

The same discipline applies to spending. Our cost-per-application guide separates bottle outlay, material consumed, and total job cost. Solids content does not replace any of those records, and none of them alone measures the quality of an install.

Solids percentage is not an ingredient percentage or a lifespan

If a label names an ingredient and a percentage, ask what the percentage is a fraction of: the supplied liquid, a prepared mixture, or the resulting film. Then ask whether the number refers to that named component or to total nonvolatile material. Do not silently relabel an ingredient claim as the total-solids value defined by a nonvolatile-content method. ASTM D2369 specifically describes total weight-percent nonvolatile matter.

This matters when a comparison places an “SiO2 percentage” beside a “solids percentage.” Unless their definitions and measurement bases align, they are not established as the same metric. The sensible next step is to ask for clarification, not reverse-engineer an undisclosed recipe or assume a universal minimum percentage for a good coating.

Likewise, the stated purpose of the two methods is volatile/nonvolatile measurement and dry-volume yield, not years of outdoor protection. You cannot convert either result into a service-life claim merely by adding a larger number to the label. D2369's significance statement and D2697's significance statement define their narrower jobs.

Keep the evidence matched to the question. For a durability comparison, ask for relevant product-specific evidence and its conditions; for handling, use the exact product's safety information. Our guide to what a coating SDS can and cannot tell you explains why a safety document should not be treated as a performance scorecard.

A practical checklist for comparing coating claims

You do not need the manufacturer's proprietary formula to have a useful buying conversation. You need enough information to understand the claim, follow the intended process, and recognize what remains uncertain. Use the following questions as a worksheet, not as a demand that every shop operate a laboratory.

• Quantity: What exactly does the percentage measure, and is it by weight or volume?
• Product: Does the value apply to the exact product and version being offered?
• Basis: Is the number measured, calculated, or a target specification?
• Method: Which method and conditions produced it, and were any departures reported?
• Scope: What conclusion does this result support, and what separate evidence supports the claimed benefit?
• Application: What surface preparation, installation, and aftercare instructions apply to your job?
• Uncertainty: Which details are unavailable, estimated, or not comparable?

A clear answer can be modest. “This is a weight-based result; we are not using it to promise a measured film thickness on your car” is more useful than an unexplained superlative. If the seller cannot supply a detail, record it as unknown; missing information is not automatically a negative test result or evidence of bad intent.

Respect the distinction between manufacturing data and skilled service. Ask a detailer to explain the preparation, application, inspection, and handover included in your quote, and direct formulation-test questions to the appropriate supplier. Do not reduce a professional's labor to the percentage printed on a bottle.

Frequently asked questions

What does solids content mean in a ceramic coating?

Ask which basis is intended. Weight-percent solids refers to nonvolatile matter by weight under the specified method, while volume nonvolatile content describes dry-coating volume obtainable from liquid volume. ASTM D2369 and ASTM D2697 describe those different measurements.

Is 60% by weight the same as 60% by volume?

No. They use different quantities and denominators, so the percentages cannot simply be substituted for one another. Confirm the reporting basis and comparable conditions before ranking products. The weight-based method and volume-based method make the distinction explicit.

Does a higher solids percentage prove longer protection?

No. The methods discussed here measure volatile/nonvolatile content or dry-volume yield, not vehicle service life. A durability claim needs evidence appropriate to that claim rather than a percentage used as a proxy. D2369 and D2697 state their measurement purposes.

Can I calculate installed film thickness from the bottle's solids number?

Not from that number alone. D2697 relates dry-coating volume to liquid volume and coverage at a specified thickness; it does not establish the application area or film deposited on your individual vehicle. Read its stated use.

Is a named ingredient percentage automatically total solids?

No. First establish what the named percentage measures and whether it refers to the liquid, prepared mixture, or film. Do not assume that an ingredient-specific claim is equivalent to total weight-percent nonvolatile matter. D2369 defines the latter measurement.

Does citing an ASTM method prove a product was tested?

No. The cited public pages describe methods, not a product-specific report for HCC or another detailing coating. Ask for the actual result and its scope before treating a method reference as product evidence. D2369 and D2697 are the method references discussed here.

Should I run an evaporation test at home?

Do not use this article as instructions to heat or evaporate coating at home. The standard assigns responsibility for appropriate safety practices to its user; request suitable documentation or qualified testing rather than improvising. See ASTM's safety limitation.

Does this article give an HCC solids percentage?

No. It does not publish or infer an HCC weight- or volume-solids percentage, and the worked numbers are hypothetical. Use the current HCC product information for the intended application, not these illustrative calculations.

How Undrdog does it

HCC Hybrid Ceramic Coating is Undrdog's all-surface flagship for cars, boats, planes, and bicycles. Its product guidance identifies exterior materials including paint, gel coat, metal, glass, PPF, vinyl, and plastic trim; confirm suitability for the specific surface and follow the current application instructions.

HCC is positioned for multi-year protection, with actual service dependent on preparation, exposure, use, and maintenance. That is not a fixed-year guarantee or a result calculated from solids content. Review HCC's current product guidance alongside the requirements of your project.

We apply the same evidence rule to our own product: no invented solids percentage, no undisclosed-formula speculation, and no claim that the ASTM pages above are HCC test reports. Start with the surface and the job, use the relevant instructions, and ask for evidence that answers the benefit you care about. A bigger number is not a substitute for a properly defined result.