M4™ Underlayment

Lightweight Dry Floor Underlayment

M4 Underlayment is a ½″ thick cementitious underlayment panel providing fire and sound ratings without poured gypsum systems. Panels install dry, accept immediate traffic, and do not add moisture to the structure.

key Properties

Weight: ~2.7 lb/ft² (86 lb per 4′×8′ sheet)

1-hour UL Classified floor/ceiling assemblies (UL L528 and UL L587)

STC/IIC ≥ 55 with tested finishes

Class A surface burn (Flame 0 / Smoke 5) per ASTM E84

Noncombustible per ASTM E136

Chloride content < 1%, resistant to mold and corrosion

Advantages

Immediate trade access and no cure time

Avoid added moisture pumped into your building

Allows immediate installation of bathroom fixtures

Factory sealed for protection from elements

Installs with nails or staples

Reduces overall floor system weight

Safe chemistry: no silica, asbestos, or formaldehyde

Applications

Multi-family residential, apartments, condos, and student housing
Assisted living, mixed-use, and hospitality projects
Modular construction

Multi-family residential, apartments, condos, and student housing

Assisted living, mixed-use, and hospitality projects

Modular and panelized construction

Download the M4 Underlayment Submittal and Installation Guide for full specifications.

Submittal

Installation Guide

Literature