What is a board foot?

One square foot of material one inch thick, a volume unit. Two hundred square feet of two-inch foam is 400 board feet; the same area in four-inch is 800. A per-square-foot price means nothing unless the thickness is stated.

Why does thickness matter acoustically?

A porous absorber works where air moves most, about a quarter wavelength from a hard surface. At 1 kHz that is three inches; at 250 Hz it is thirteen. Each doubling of thickness buys roughly an octave of absorption.

Can I get low-frequency absorption without thick foam?

Often yes. Mounting thinner foam on standoffs with an air gap behind moves it towards the quarter-wavelength position for lower frequencies. The standoffs cost less than the foam would.

Fiber is generally cheaper per unit of absorption and handles heat better; foam is cleaner to handle and easier to profile. Price both, then decide on the non-price factors, which usually decide it anyway.

Acoustic, Noise, Vibration & NVH Products calculator

Acoustic Foam Cost Calculator (Board Feet)

Price an acoustic foam job the way foam is bought. Enter area, thickness, price per board foot and cutting yield; the page returns total cost and a waste-loaded unit price for comparing quotes.

What this calculator does

Price acoustic foam on the basis it is sold and works: volume in board feet, with thickness visible rather than buried in a rate.

Formula used

Net board feet = area × thickness in inches (one board foot = 1 ft² at 1 in)
Board feet to buy = net board feet ÷ cutting yield
Total foam cost = board feet to buy × price per board foot
Delivered cost per ft² = total foam cost ÷ area treated
Cutting waste = total cost − net board feet × price; loaded price = price ÷ yield

Inputs explained

Area to Treat: Surface area the foam covers, before any cutting allowance.
Foam Thickness: Nominal thickness; it drives both cost and low-frequency absorption.
Foam Price per Board Foot: Price for one square foot at one inch thick.
Cutting Yield: Share of purchased foam that ends up installed.

How to use the result

Best suited to comparing foam quotes at different thicknesses, costing the step from two-inch to four-inch foam, deciding between pre-cut profiles and in-house cutting.
Prices material only; adhesive, fixings, labor, freight and cutting charges are separate. Predicts no acoustic performance, only what the volume costs. Ignores minimum order quantities and bun sizes, which can dominate small jobs.

Common questions

What is a board foot? One square foot of material one inch thick, a volume unit. Two hundred square feet of two-inch foam is 400 board feet; the same area in four-inch is 800. A per-square-foot price means nothing unless the thickness is stated.
Why does thickness matter acoustically? A porous absorber works where air moves most, about a quarter wavelength from a hard surface. At 1 kHz that is three inches; at 250 Hz it is thirteen. Each doubling of thickness buys roughly an octave of absorption.
Can I get low-frequency absorption without thick foam? Often yes. Mounting thinner foam on standoffs with an air gap behind moves it towards the quarter-wavelength position for lower frequencies. The standoffs cost less than the foam would.
Foam or fiber? Fiber is generally cheaper per unit of absorption and handles heat better; foam is cleaner to handle and easier to profile. Price both, then decide on the non-price factors, which usually decide it anyway.

Last reviewed 2026-10-01.