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How to specify a Natural Stone

What to put on an RFQ for Natural Stone: the ratings, documents, and constraints that change the quote.

25 Oct 2026 · 3 min read · Tradinor Desk

Specification points for Natural StoneTRADINOR · FIGUREWhat to lock for Natural StoneStandardExposureFire and thermalTraceability
Put these on the RFQ for Natural Stone before you compare prices.

A buyer searching for Natural Stone is usually trying to stop a bad substitute. A building material is specified by the grade, the dimensions, the standard, and the exposure of the assembly. The notes below are selection criteria for a Natural Stone. They are not a catalog promise. Confirm every rating on the current datasheet, drawing, or test report for the revision you will receive.

What has to be true of Natural Stone

A building material is specified by the grade, the dimensions, the standard, and the exposure of the assembly. For a Natural Stone, start from the duty, then the interface to the rest of the machine or the room, then the document that proves the claim. A lower price that leaves one of those blank is a different product.

Natural Stone is easy to confuse with PU Foam Board. If the quote could be read as either, add the line that separates them: the rating, the fitment, or the standard named below. Link the drawing number to that line so receiving inspection can reject the wrong one.

Numbers that change the quote

Line What to write for Natural Stone
Standard The product standard the supplier will mark on the delivery.
Exposure Interior, exterior, wet, or structural.
Fire and thermal Any fire class or insulation value the assembly needs.
Traceability Lot or mill documents when the work is structural.
Grade Strength, class, or mix, using the name the standard uses.
Dimensions Size, thickness, and tolerance.

How to compare two offers

Lay both quotes for Natural Stone on one sheet and line up standard, exposure, and fire and thermal. If a cell is empty, the offer is not finished. Ask for the missing line in writing. When those match, the honest difference is lead time, the test evidence, and who carries the warranty. Do not average a fully specified Natural Stone with a cheaper line that omitted standard.

Documents worth having before the deposit

Ask for the declaration of performance or the mill certificate the market expects. The file should name Natural Stone and the revision, not only the supplier’s homepage. A factory quality certificate such as ISO 9001 can sit beside that file. It does not replace it.

Failures that show up after delivery

  • Cutting a rated assembly and assuming the fire class survived.
  • Accepting a visual match with a lower strength class.
  • Leaving moisture and storage out of a cement or timber order.

On a Natural Stone, the expensive version of the first mistake is discovering it after the goods are in the crate. Put the rejection condition in the purchase order while the supplier can still restate the offer.

A worked RFQ line

Use this shape, then replace the brackets with your duty: “Natural Stone — State grade, dimensions, standard, exposure, and documents.” That sentence is a template, not a rating of any brand. If a supplier’s datasheet uses different units, convert them onto this sheet so the next offer can be compared.

Where words like waterproof / IP65 belong

Searches often add a constraint to Natural Stone: waterproof / IP65, or stainless / corrosion. Keep those on this page. IP65 in IEC 60529 means dust-tight and protected against water jets. Write that code if hoses are the real exposure. The word waterproof alone does not name a test. Name the alloy or the coating and the chemical it must survive. Stainless is a family, not a guarantee. If you need a third constraint, add it as another line on the same drawing. A second URL that only swaps the adjective does not give a buyer a second fact.

Related in this section: how to specify PU Foam Board.

Questions buyers actually ask

What should an RFQ for Natural Stone include?

State grade, dimensions, standard, exposure, and documents.

Is a cheaper Natural Stone the same part?

Only if standard, exposure, and the documents match. A missing line is a different offer.

Do waterproof, OEM, or IP words need their own page?

No. For Natural Stone they are extra lines on this specification. Ask for the test or the drawing that gives the word a value.