Every construction product has one document that governs it: the technical data sheet. Sales decks, brochures, and case studies explain and persuade; the TDS defines. Learning to read one quickly is the single most useful document skill an owner, contractor, or specifier can build, because it converts product conversations from adjectives into checkable statements.
The sections that matter, in order
1. Product description
What is it? Look for the mechanism in the first paragraphs: film-forming or penetrating, reactive or barrier, what chemistry family. This is where a product's true category is stated. If a TDS says "reacts below the surface," it is a penetrating chemistry; if it specifies wet film thickness and dry film thickness, it is a coating.
2. Application rate and coverage
The most practically important numbers on the page. Application rate (square feet per gallon) determines cost, and honest TDS documents give ranges that vary with substrate porosity, because absorption varies enormously between substrates. A single, unconditional coverage number is a flag; a range with substrate conditions is a sign the supplier understands real surfaces.
3. Surface preparation
What the substrate must be before application: clean, sound, free of films and contaminants, sometimes with specified absorbency (many penetrating products require the surface to darken and absorb water when dampened). For penetrating treatments this section is make-or-break: product that cannot reach the paste cannot react with it.
4. Conditions and cure times
Temperature windows, moisture conditions, time to traffic, time before subsequent coatings. These fields tell you the real-world logistics, and they define application and return-to-service conditions. Read them before the project, not after a problem.
5. Test references
Any performance claim worth considering points to a test method. Check which standard (ASTM, other), what was measured, and whether the result is stated for the product on a defined substrate against a control. This is the boundary between a claim and a measurement; our test interpretation article and C1202 explainer cover two common examples where test names oversimplify what was measured.
6. Limitations and compatibility
The most valuable and least-read section. It tells you what the product does not do, what it is not compatible with, and what conditions void the expectations. A TDS without a limitations section should raise more questions than it answers.
The four document types and their weight
| Document | What it is | What it establishes |
|---|---|---|
| TDS | Manufacturer's governing technical statement | What the product is and how to use it |
| SDS | Safety data sheet | Hazards, handling, PPE; not performance |
| Test report | Laboratory result on specific specimens | What happened to those specimens under that method |
| Case study | Narrative of a project | That the product was used somewhere, with stated outcomes |
Each answers a different question, and none substitutes for another. An SDS proves nothing about performance; a case study proves nothing about your substrate; a test report proves only what its method measured. Competition Bureau guidance on performance claims is explicit that claims must be based on adequate and proper testing, which is exactly why tracing every claim to its document matters.
Red flags while reading
- Superlatives without test references (strongest, ultimate, revolutionary).
- Permanence claims without qualification.
- Coverage given as one number with no substrate conditions.
- Test names cited without results, or results without the test method.
- Compatibility with "everything" and no limitations section.
A worked discipline
Take any product you are considering and mark up its TDS with three questions:
- What will this do on my substrate (as distinct from on the lab specimen)?
- What are the three most likely failure conditions listed in the limitations?
- For every performance claim I care about: which test, which control, which result?
If the TDS cannot answer those, the next step is to ask the supplier for the underlying report, not to assume.
The SDS: what it is for and what it is not
The safety data sheet rides along with every product, and it is routinely misread in one of two directions:
- It is not a performance document. Nothing in an SDS establishes durability, penetration, or any performance property; its chemistry and hazard information describe handling, not results.
- It is not optional reading. The SDS defines PPE, handling constraints, incompatible materials, and spill response. For silicate treatments, the classic field items are glass and aluminum (etching per the SDS), alkaline pH handling, and overspray protection; for coatings and solvents, the ventilation and flammability sections matter.
A project that has read the TDS and not the SDS is half-informed; both documents belong in the project file (our PRO Tek overview cites both for one product as an example).
Questions to ask a supplier, with the answers that should follow
A short script for vendor conversations, with the shape of a good answer:
- "Which test supports this claim, and can I see the report?" Good: method named, report provided, control stated. Weak: "lab tested" without designation.
- "What substrate were the results on, and how does mine compare?" Good: acknowledges substrate dependence, proposes a mock-up. Weak: one number claimed to apply everywhere.
- "What does this product not do?" Good: names boundaries confidently. Weak: "it does everything you need."
- "What is the current TDS revision?" Good: sends the controlled document with revision date. Weak: a summary sheet or a brochure.
The pattern across all four: the supplier's willingness to show documents is itself evidence about the claims behind them.
What this article does not tell you
It does not evaluate any specific manufacturer's documents, and it does not replace project specification work. Its purpose is to make you faster and more accurate when the documents are in front of you.
Where to go next
What Is PRO Tek Concrete? An Evidence-Led Overview applies this discipline to a real product, and How to Read PRO Tek's Test Evidence walks through actual laboratory results. Questions Municipalities Should Ask Vendors style checklists pair naturally with this skill.