Burning MDF (Medium-Density Fiberboard): Is It Safe?

Orange Dancing Flame
Photograph by Dann McKenzie- www.fineartphoto.ca / Getty Images

Considering how much MDF is filling today's homes in the form of window and door trim and cabinets, it stands to reason that this stuff has to eventually be removed.  But how do you dispose of it?

Because MDF is so brittle, you can easily snap trim into foot-long sections and throw it in your regular garbage run.  MDF panels are tougher to break, but they will yield under the force of a framing hammer.

What about burning it?

Many homes now have outdoor fireplaces or indoor wood stoves, perfect places to burn up unwanted building materials.  Would burning MDF in either place affect your health?

MDF Is Laced With Formaldehyde

MDF stands for medium-density fiberboard, and it is not 100% wood. It is basically a wood byproduct, made of wood chips and particles combined with binders and other resins to harden it into sheets.

The real issue is with the hazardous substance urea-formaldehyde, which is used in the manufacture of MDF.

HPVA and Certification

It is such a concern that MDF is often issued with what is called a HPVA Formaldehyde Emission Property Verification Certificate that essentially says that, yes, there is formaldehyde in the product, but it does fall below maximum formaldehyde emission levels.

HPVA is the acronym for the Hardwood Plywood and Veneer Association, and its Reston VA-based lab conducts various types of tests (not just formaldehyde-related) on plywood, MDF, and other wood products.

It should be noted that the HPVA's formaldehyde test does not involve burning of MDF.

What Do Homeowners Say?

Anecdotal evidence on remodeling forums reveals that there are two types of people who burn MDF: those who burn MDF simply to dispose of it and those who burn it because they want to heat their homes, chiefly with wood burning stoves.

One forum member claims that he has burned MDF for "over thirty years" with no adverse health effects.

What Do the Experts Say?

Since anecdotal advice from anonymous people on the Internet may not be a good approach where your health is concerned, an expert who deals with MDF testing gave us a more informed answer.

Brian Sause, Director of Testing, Certification, & Standards at the HPVA Lab tells us:

The makeup of a fiberboard panel is dependent on the desired properties of the final product. There is a high degree of variability in the products with regard to wood fiber content and alignment, adhesive or resin type used, and other additives to adjust the performance of the panels.
I would agree that, as a general precaution, you should consider any composite material unsafe to burn in a household environment due to the unknown makeup. While there are concerns over high emitting products containing formaldehyde in an indoor air environment, toxicity of any combustible materials when ignited is a much greater concern.
HPVA's certification of engineered wood products ensures that they do not contribute to elevated levels of formaldehyde in the home.
Formaldehyde naturally occurs in raw wood and even in the human body. A certification does not mean that the products do contain additional formaldehyde, but maintains that they are safe and controlled under anticipated conditions of normal use.
For those who are concerned, there are many products available to consumers on the market today that are certified as No-Added Formaldehyde (NAF) and Ultra-Low Emitting Formaldehyde (ULEF) products.