To try and get a handle on all the facets of being green when it comes to interior design, building materials, and the like, I decided to explore a material widely used in interior finishing work, furniture manufacture and more recently in custom framing as well: medium density fiber board, known mainly as MDF.
At the HD Expo, I stopped to speak with one contract framer who had a US Green Building Council Certificate up on their booth and some other “green” group signage– I don’t remember what exactly, because of their response to my question: “So what green products do you offer for our (art & framing) industry?”.
The salesman held up a frame corner sample made of MDF with a silver foil finish, claiming it was a green product. When I asked what else made them a “green company”, he had nothing else to say.
When I pressed, his claim for MDF being green rested mainly on the idea that MDF is a “recycled” product, utilizing either post-consumer waste or wood industry by-products in its manufacture. Further, he couldn’t tell me where the MDF came from (company or country) or how it was actually made or how much of it actually came from recycled raw materials. (Most people are probably familiar with the phrase “Contains 30% recycled content”, or 40% or more, when discussing paper products like coffe cups or newsprint).
Now, even if the “recycled content” claim were true, there are several other factors to consider when determining if a building product is green. I will look into these considerations over the next couple of posts; for now lets discuss MDF and how green it may be in terms of its origins and manufacture.
A little research shows that the preferred raw material for MDF is wood fiber, properly prepared from virgin trees. Most commonly used are fast growing softwoods like the radiata pine used in Australian and New Zealand manufacture of MDF. These trees are raised on plantations like Christmas trees, harvested and replanted in rotation to ensure a steady supply of ready-to-use logs.
Well managed forests and plantations are definitely the foundation of a sustainable wood product industry, its important to distinguish between the use of virgin materials and recycled materials in the discussion of what’s green.
One reason for this is that there is a considerable amount of waste in the wood industry and it makes sense to put this waste to work in engineered wood products like plywood, particle board, oriented strand board and MDF. If these products are not being made from waste, where does the waste go?
A second reason is the amount of energy consumed in the manufacture of these products. For instance, if we follow a fresh log on its path to becoming MDF, there is a considerable amount of energy consumed by:
1. The “debarking” process, where a machine peels away the bark from the log.
2. The chipper that grinds our log up into small pieces.
3. The “plugging and heating” of the chips that prepares them for the next stage,
4. Where the wood fibers are actually stripped apart by a “defibrator”.
5. Next the fibers are injected with resin and wax in a “blowline”, which processes the fibers with more heat at high velocity so that they will
6. Bond together consistently in an oscillating “pendistor”.
7. The homogenized mass leaves the pendistor to be pressed flat into sheets under high pressure.
8. The pressed sheets are then trimmed and sanded for final delivery.
Imagine the amount of electricity or other fuels required for this manufacturing process– only a small amount can be supplied by waste products from the process (for example, the bark can be burned to heat the fibers) and so must come from other fuels.
Why go through all this?
As a builder and furniture maker as well as picture framer, I know that MDF has wonderful capabilities unavailable in other products: large sheets that are perfectly true, stable, won’t warp, takes paint and laminates with ease, and are consistent from batch to batch.
To produce modern furniture and case work, especially in the volume demanded by hospitality and contract work, MDF is a godsend and its many uses certainly (from the furniture maker’s point of view) ought to justify the energy expended in its manufacture.
As a picture framer I have my doubts, since picture frame moulding is generally speaking long thin strips (similar to the natural shape of trees), what could there to be gained from going through all of this effort to produce big perfect sheets of MDF just to turn around and cut them into the little pieces required for framing?
Maybe if the sheets were 100% recycled and most of the electricty/heat required for processing was generated from wind and solar power, I could get excited about MDF as a “green” product.
