Joist Floors

Data analysis

The calculations may be used for any type of joist: solid wood joists, wood truss joists, C-section steel joists or wood I-joists. Research so far shows no difference in sound transmission that can be attributed to joist type.
Make your choice of materials below and click on calculate.

Concrete topping : mm thick.

Subfloor : layers mm thick

Joists : mm deep, mm o.c.

Sound-absorbing material: mm thick

Resilient metal channels : mm o.c.

Ceiling : layers mm thick

STC ±1.6     IIC ±1.8     ALD100 ±1.6     Lnw  ±1.8  


All or part of the calculation history below can be highlighted by dragging over it with the mouse and then copying it (ctrl-C) and pasting it into an editor (ctrl-V).