Absorption coefficients of common building materials and finishes
Floor materials |
125 Hz |
250 Hz |
500 Hz |
1 kHz |
2 kHz |
4 kHz |
Carpet |
0.01 |
0.02 |
0.06 |
0.15 |
0.25 |
0.45 |
Concrete (unpainted, rough finish) |
0.01 |
0.02 |
0.04 |
0.06 |
0.08 |
0.1 |
Concrete (sealed or painted) |
0.01 |
0.01 |
0.02 |
0.02 |
0.02 |
0.02 |
Marble or glazed tile |
0.01 |
0.01 |
0.01 |
0.01 |
0.02 |
0.02 |
Vinyl tile or linoleum on concrete |
0.02 |
0.03 |
0.03 |
0.03 |
0.03 |
0.02 |
Wood parquet on concrete |
0.04 |
0.04 |
0.07 |
0.06 |
0.06 |
0.07 |
Wood flooring on joists |
0.15 |
0.11 |
0.1 |
0.07 |
0.06 |
0.07 |
Take a look at the JCW Acoustic Supplies range of Floor Soundproofing products.
Seating Materials |
125 Hz |
250 Hz |
500 Hz |
1 kHz |
2 kHz |
4 kHz |
Benches (wooden, empty) |
0.1 |
0.09 |
0.08 |
0.08 |
0.08 |
0.08 |
Benches (wooden, 2/3 occupied) |
0.37 |
0.4 |
0.47 |
0.53 |
0.56 |
0.53 |
Benches (wooden, fully occupied) |
0.5 |
0.56 |
0.66 |
0.76 |
0.8 |
0.76 |
Benches (cushioned seats and backs, empty) |
0.32 |
0.4 |
0.42 |
0.44 |
0.43 |
0.48 |
Benches (cushioned seats and backs, 2/3 occupied) |
0.44 |
0.56 |
0.65 |
0.72 |
0.72 |
0.67 |
Benches (cushioned seats and backs, fully occupied) |
0.5 |
0.64 |
0.76 |
0.86 |
0.86 |
0.76 |
Theater seats (wood, empty) |
0.03 |
0.04 |
0.05 |
0.07 |
0.08 |
0.08 |
Theater seats (wood, 2/3 occupied) |
0.34 |
0.21 |
0.28 |
0.53 |
0.56 |
0.53 |
Theater seats (wood, fully occupied) |
0.5 |
0.3 |
0.4 |
0.76 |
0.8 |
0.76 |
Seats (fabric-upholsterd, empty) |
0.49 |
0.66 |
0.8 |
0.88 |
0.82 |
0.7 |
Seats (fabric-upholsterd, fully occupied) |
0.6 |
0.74 |
0.88 |
0.96 |
0.93 |
0.85 |
See our Cinema and theatre room products and solutions.
Reflective wall materials |
125 Hz |
250 Hz |
500 Hz |
1 kHz |
2 kHz |
4 kHz |
Brick (natural) |
0.03 |
0.03 |
0.03 |
0.04 |
0.05 |
0.07 |
Brick (painted) |
0.01 |
0.01 |
0.02 |
0.02 |
0.02 |
0.03 |
Concrete block (coarse) |
0.36 |
0.44 |
0.31 |
0.29 |
0.39 |
0.25 |
Concrete block (painted) |
0.1 |
0.05 |
0.06 |
0.07 |
0.09 |
0.08 |
Concrete (poured, rough finish, unpainted) |
0.01 |
0.02 |
0.04 |
0.06 |
0.08 |
0.1 |
Doors (solid wood panels) |
0.1 |
0.07 |
0.05 |
0.04 |
0.04 |
0.04 |
Glass (1/4″ plate, large pane) |
0.18 |
0.06 |
0.04 |
0.03 |
0.02 |
0.02 |
Glass (small pane) |
0.04 |
0.04 |
0.03 |
0.03 |
0.02 |
0.02 |
Plasterboard (12mm (1/2″) paneling on studs) |
0.29 |
0.1 |
0.06 |
0.05 |
0.04 |
0.04 |
Plaster (gypsum or lime, on masonry) |
0.01 |
0.02 |
0.02 |
0.03 |
0.04 |
0.05 |
Plaster (gypsum or lime, on wood lath) |
0.14 |
0.1 |
0.06 |
0.05 |
0.04 |
0.04 |
Plywood (3mm(1/8″) paneling over 31.7mm(1-1/4″) airspace) |
0.15 |
0.25 |
0.12 |
0.08 |
0.08 |
0.08 |
Plywood (3mm(1/8″) paneling over 57.1mm( 2-1/4″) airspace) |
0.28 |
0.2 |
0.1 |
0.1 |
0.08 |
0.08 |
Plywood (5mm(3/16″) paneling over 50mm(2″) airspace) |
0.38 |
0.24 |
0.17 |
0.1 |
0.08 |
0.05 |
Plywood (5mm(3/16″) panel, 25mm(1″) fiberglass in 50mm(2″) airspace) |
0.42 |
0.36 |
0.19 |
0.1 |
0.08 |
0.05 |
Plywood (6mm(1/4″) paneling, airspace, light bracing) |
0.3 |
0.25 |
0.15 |
0.1 |
0.1 |
0.1 |
Plywood (10mm(3/8″) paneling, airspace, light bracing) |
0.28 |
0.22 |
0.17 |
0.09 |
0.1 |
0.11 |
Plywood (19mm(3/4″) paneling, airspace, light bracing) |
0.2 |
0.18 |
0.15 |
0.12 |
0.1 |
0.1 |
Absorptive wall materials |
125 Hz |
250 Hz |
500 Hz |
1 kHz |
2 kHz |
4 kHz |
Drapery (10 oz/yd2, 340 g/m2, flat against wall) |
0.04 |
0.05 |
0.11 |
0.18 |
0.3 |
0.35 |
Drapery (14 oz/yd2, 476 g/m2, flat against wall) |
0.05 |
0.07 |
0.13 |
0.22 |
0.32 |
0.35 |
Drapery (18 oz/yd2, 612 g/m2, flat against wall) |
0.05 |
0.12 |
0.35 |
0.48 |
0.38 |
0.36 |
Drapery (14 oz/yd2, 476 g/m2, pleated 50%) |
0.07 |
0.31 |
0.49 |
0.75 |
0.7 |
0.6 |
Drapery (18 oz/yd2, 612 g/m2, pleated 50%) |
0.14 |
0.35 |
0.53 |
0.75 |
0.7 |
0.6 |
Fiberglass board (25mm(1″) thick) |
0.06 |
0.2 |
0.65 |
0.9 |
0.95 |
0.98 |
Fiberglass board (50mm(2″) thick) |
0.18 |
0.76 |
0.99 |
0.99 |
0.99 |
0.99 |
Fiberglass board (75mm(3″) thick) |
0.53 |
0.99 |
0.99 |
0.99 |
0.99 |
0.99 |
Fiberglass board (100mm(4″) thick) |
0.99 |
0.99 |
0.99 |
0.99 |
0.99 |
0.97 |
Open brick pattern over 75mm(3″) fiberglass |
0.4 |
0.65 |
0.85 |
0.75 |
0.65 |
0.6 |
Pageboard over 25mm(1″) fiberglass board |
0.08 |
0.32 |
0.99 |
0.76 |
0.34 |
0.12 |
Pageboard over 50mm(2″) fiberglass board |
0.26 |
0.97 |
0.99 |
0.66 |
0.34 |
0.14 |
Pageboard over 75mm(3″) fiberglass board |
0.49 |
0.99 |
0.99 |
0.69 |
0.37 |
0.15 |
Performated metal (13% open, over 50mm(2″) fiberglass) |
0.25 |
0.64 |
0.99 |
0.97 |
0.88 |
0.92 |
See our Wall soundproofing products and solutions.
Ceiling Material |
125 Hz |
250 Hz |
500 Hz |
1 kHz |
2 kHz |
4 kHz |
Plasterboard (12mm(1/2″) in suspended ceiling grid) |
0.15 |
0.11 |
0.04 |
0.04 |
0.07 |
0.08 |
Underlay in perforated metal panels (25mm(1″) batts) |
0.51 |
0.78 |
0.57 |
0.77 |
0.9 |
0.79 |
Metal deck (perforated channels,25mm(1″) batts) |
0.19 |
0.69 |
0.99 |
0.88 |
0.52 |
0.27 |
Metal deck (perforated channels, 75mm(3″) batts) |
0.73 |
0.99 |
0.99 |
0.89 |
0.52 |
0.31 |
Plaster (gypsum or lime, on masonary) |
0.01 |
0.02 |
0.02 |
0.03 |
0.04 |
0.05 |
Plaster (gypsum or lime, rough finish or timber lath) |
0.14 |
0.1 |
0.06 |
0.05 |
0.04 |
0.04 |
Sprayed cellulose fiber (16mm(5/8″) on solid backing) |
0.05 |
0.16 |
0.44 |
0.79 |
0.9 |
0.91 |
Sprayed cellulose fiber (25mm(1″) on solid backing) |
0.08 |
0.29 |
0.75 |
0.98 |
0.93 |
0.76 |
Sprayed cellulose fiber (25mm(1″) on timber lath) |
0.47 |
0.9 |
1.1 |
1.03 |
1.05 |
1.03 |
Sprayed cellulose fiber (32mm(1-1/4″) on solid backing) |
0.1 |
0.3 |
0.73 |
0.92 |
0.98 |
0.98 |
Sprayed cellulose fiber (75mm(3″) on solid backing) |
0.7 |
0.95 |
1 |
0.85 |
0.85 |
0.9 |
Wood tongue-and-groove roof decking |
0.24 |
0.19 |
0.14 |
0.08 |
0.13 |
0.1 |
See our Ceiling soundproofing products and solutions.
Miscellaneous surface material |
125 Hz |
250 Hz |
500 Hz |
1 kHz |
2 kHz |
4 kHz |
People-adults (per 1/10 person) |
0.25 |
0.35 |
0.42 |
0.46 |
0.5 |
0.5 |
People-high school students (per 1/10 person |
0.22 |
0.3 |
0.38 |
0.42 |
0.45 |
0.45 |
People-elementary students (per 1/10 person) |
0.18 |
0.23 |
0.28 |
0.32 |
0.35 |
0.35 |
Ventilating grilles |
0.3 |
0.4 |
0.5 |
0.5 |
0.5 |
0.4 |
Water or ice surface |
0.008 |
0.008 |
0.013 |
0.015 |
0.02 |
0.025 |