Particleboard or Pressboard—Will They Fully Off-Gas?

October 10, 2010, by Debra Lynn Dadd

Question from wt

We're remodeling my house, and my husband put some "sound board" on the studs under the dry wall to help with sound reduction. this "sound board" smells HORRIFFIC! it seems very similar to particle/press board. we're hoping that placing the dry wall over it, would essentially seal it, so the smell/toxicity cannot come out. however, not sure if that theory will work. or, are considering getting rid of the sound board all together. 

if, in fact, this sound board is similar in composition to press board/particle board....do these types of materials EVENTUALLY FULLY OUTGAS? or is this something that does not, and needs to be 'sealed' with some sort of sealant? 

knowing the answer to that question, would help us to determine how to proceed with this project. 

and real quick, on the topic of press board: if i have a press board dresser from ikea...will this eventually outgas? (I've had these drawers for about 3-4 years..and my it still stinks!) my clothes left in it, wreak of the formaldehyde (ick!). since i wear primarily 100% cotton, are my natural fabrics absorbing the formaldehyde from the drawers??!! :O 

would appreciate your thoughts.. 

Debra's Answer

First, "particleboard" and "pressboard" are two different things.

Particleboard is made of wood shavings held together with a formaldehyde-based resin that outgasses. You can see the wood shavings throughout the board on both the flat side and the cut side and it has an odor--strong when new.

Pressboard is made from smaller wood fibers that are held together by a process using pressure and steam. It is a thin, brown board, with one smooth side and one textured side. It comes in a solid sheet and perforated with holes to make "peg board". Pressboard does not have a strong odor and I consider it to be a nontoxic product.

It sounds like what you have installed is particleboard, or a similar product.

Formaldehyde offgasses from particleboard until there is no more formaldehyde to offgas. It is very intense when the particleboard is new and decreases over time. I read that the half life of formaldehyde in particleboard is three to six years, but can still contribute to indoor air pollution 12 to 24 years after installation (Spectrum--Newsletter of the Society Promoting Environmental Conservation, Vol 26, No. 1). This seems reasonable to me. How long any given installation takes to full outgas depends on the conditions. More heat will make it outgas faster.

There is a product which can be applied to particleboard to block fumes, made by AFM Enterprises. I used this product many years ago with success, when I purchased a table that I thought was solid wood, which actually contained one piece of particleboard about 1' x 3' one inch thick. I applied the vapor barrier finish and was able to use the table with no problem.