ASTM C639-24 PDF

Full title and description

ASTM C639-24 — Standard Test Method for Rheological (Flow) Properties of Elastomeric Sealants. This concise test method describes laboratory procedures to determine the flow (rheological) behavior of single‑ and multi‑component chemically curing elastomeric sealants used in building construction, and defines classification of sealant flow types (flowable/self‑leveling vs. non‑sag) for comparative testing and specification purposes.

Abstract

This test method specifies procedures to measure horizontal and vertical flow (slump/sag) of elastomeric joint sealants when placed in standardized channels and conditioned at specified temperatures. It covers single‑component and multi‑component sealants and defines four classification types (Type I–IV) based on component count and flow behavior. Values are reported in SI units; results are intended for laboratory comparison and quality control.

General information

• Status: Active standard (current edition).
• Publication date: 2024 (ASTM C639‑24; current 2024 edition, last updated Nov 2024).
• Publisher: ASTM International.
• ICS / categories: 91.100.50 — Binders; sealing materials.
• Edition / version: C639‑24 (2024 edition).
• Number of pages: 3.

Scope

This method provides a laboratory procedure for determining rheological (flow) properties of chemically curing elastomeric sealants intended for building construction. It applies to both single‑component (ready‑to‑use) and multi‑component (base + activator/curing agent) sealants and describes testing for horizontal flow (self‑leveling) and vertical slump (non‑sag) under controlled temperatures. The standard identifies four product types: Type I — single‑component flowable/self‑leveling; Type II — single‑component non‑sag; Type III — multi‑component flowable/self‑leveling; Type IV — multi‑component non‑sag. Test results are comparable only for samples conditioned at the same temperature and are reported in SI units.

Key topics and requirements

• Definition of test specimen channels and dimensions for evaluating flow and slump.
• Conditioning requirements (temperatures and times) for sealant components and test channels prior to measurement.
• Procedures for horizontal flow (self‑leveling) and vertical slump (non‑sag) observations and measurement.
• Classification of sealants into four types based on component count and flow behavior (Types I–IV).
• Reporting in SI units and guidance that only samples conditioned identically are directly comparable.
• Notes on optional, purchaser‑specified flow characteristics (special non‑sag or lower flow behavior for sloping joints).
• General safety/responsibility statement: users must address applicable health, safety and environmental practices before use.

Typical use and users

Used by test laboratories, sealant manufacturers, product development teams, quality control personnel, specifiers, architects and contractors to characterize and specify the flow behavior of elastomeric joint sealants. It supports product classification, acceptance testing, R&D comparisons, and specification compliance in building envelope and joint‑sealing applications.

Related standards

Commonly referenced alongside other ASTM C24 committee documents and sealant standards such as ASTM C920 (Specification for Elastomeric Joint Sealants), tests for hardness and cure behavior (e.g., C661, C679), adhesion and peel tests (e.g., C794, C1135), laboratory practice guidance (C1021) and extrusion/flow tests (C1183). These related standards address complementary performance attributes (adhesion, cohesion, hardness, weathering, extrusion rate) used with C639 flow results in full product evaluation.

Keywords

rheology, flow, slump, sag, elastomeric sealant, joint sealant, non‑sag, self‑leveling, single‑component, multi‑component, C639, ASTM, sealant testing

FAQ

Q: What is this standard?

A: ASTM C639‑24 is a short test method that defines laboratory procedures for measuring rheological (flow) properties—horizontal flow and vertical slump—of elastomeric sealants used in building construction.

Q: What does it cover?

A: It covers preparation, conditioning, and measurement of sealant samples in standardized channels to evaluate flowable (self‑leveling) and non‑sag behavior for both single‑ and multi‑component chemically curing sealants; it also classifies sealants into four types (I–IV) based on component count and flow behavior.

Q: Who typically uses it?

A: Manufacturers, independent testing laboratories, specifiers, architects, contractors and quality control groups use the method for product development, specification compliance, acceptance testing and comparative performance assessment.

Q: Is it current or superseded?

A: The C639‑24 edition is the current ASTM edition (2024). Users should confirm they are working to the latest revision published by ASTM International for formal procurement or compliance needs.

Q: Is it part of a series?

A: It is part of the body of ASTM C24 committee standards addressing building seals and sealants; it is used in conjunction with related specifications and test methods (for adhesion, hardness, extrusion rate, weathering, etc.) to form a complete evaluation suite for sealant products.

Q: What are the key keywords?

A: Rheology, flow, slump, sag, elastomeric sealant, self‑leveling, non‑sag, single‑component, multi‑component, joint sealant, ASTM C639.