Agglomerates, also known as wood conglomerates, are a very popular and common material for the manufacture of all types of indoor furniture. It can be said without risk of being wrong, that together with MDF, they replaced solid wood as the main material for the manufacture of furniture.
The reasons are in its excellent quality / price ratio. In other words, it offers properties or characteristics that are more than acceptable, which have also been improving thanks to the improvement of the manufacturing process and the incorporation of new materials, at a comparatively low price.
As a definition we can say that it is a compound formed by particles or wood chips to which glues and thermoset resins are added. Heat and pressure are applied to this agglomerate until the plate is obtained. The result may vary depending on the wood used, the adhesives and other additives, the pressure applied, etc.
A common practice during the manufacturing process is to use thicker wood particles for the interior and before pressing to add the finer particles to obtain a smoother surface before applying the final coating.
Different woods can be used to make pellets. The most used are soft woods, mainly conifers, such as pine, although others such as poplar or eucalyptus can also be used. Burnt wood is sometimes even used in fires that possibly could not have been used for other purposes.
Ease of work and machining.
Stable and uniform. As long as they do not come into contact with humid environments.
Excellent quality / price ratio.
They can be covered with melamine or other products, which allows reaching any style or design that we want.
Good resistance. It is certainly not the hardest wood, but taking into account the use for which the card was designed offers a very good result.
It allows a better use of the tree. Not only recycled wood is used, but also pieces that would be discarded. If we add to this that they can be recycled, some classify them as material ecologically sustainable.
Resistance limited to moisture. Therefore, they are recommended only in dry environments, and only indoors. When they come into contact with water, they swell and do not return completely to their original state. The problem is less the greater the density of the plate.
They do not offer a completely smooth surface. Although agglomerates with a very smooth surface are now obtained, it is not completely smooth. In the case of cheap or low-end agglomerates, this issue represents a major problem, since these irregularities are they telegraph and can be seen even when the card is coated.
Formaldehyde content. It is a chemical product classified as harmful to health in certain concentrations and which is used as a component in adhesives for the manufacture of chipboard panels. Its presence has been drastically reduced in recent years and practically all manufacturers have their products classified as E1 (low formaldehyde content, practically zero) and some have even eliminated it.
There is no possibility of repair. Whether they swell or crack, they cannot be repaired.
Embroidering or leafing is necessary. This is a process that consists of fixing a sheet, usually PVC, although other materials can be used, to the edge of a board after cutting. If we did not do this, the exposed edges of the card would offer a bad result, not only from an aesthetic point of view, but also a weak point against moisture and the possibility of chipping of the card.
Types of clusters
There are basically 5 types of card:
- Pattern. In this case, we will mention the one that does not have or has not been added additional features. That is, its resistance to moisture or fire has not been improved and is not coated.
- Flame Retardant. In this case, flame retardant additives are added to your composition. Thanks to this, the action of the fire is delayed. Usually, a red ink is also added to identify them. The demand usually comes from areas where fire legislation is more demanding: hotels, offices, public buildings, fairs …
- Waterproof. Moisture-repellent or moisture-repellant chipboards offer better moisture resistance. This does not mean that they are immune. For its manufacture, the percentages of wood and binder, and their composition, are changed. It is common to add green dye to facilitate identification. It can be used as a base for floors and in the manufacture of furniture in humid environments such as kitchens and bathrooms.
- Illuminated. Sometimes, a lighter type of card may be desirable, for example, for making doors. When this is the goal, the chipboard will not only be composed of wood, but also of other materials, such as some synthetic polymers. On the one hand, they must be lighter than wood and, on the other hand, have no negative effects on the physical-mechanical resistance of the unit.
- Decorative or Coated:
- All of these types of agglomerate combine, that is, we can buy a water-repellent agglomerate coated with melamine.
Measurements and prices
The most common thicknesses are 10, 16, 19, 22 and 30 millimeters.
In terms of dimensions (length x width) 244 × 122 centimeters is the most common, although 285 × 210, 244 × 250 and 366 × 205 centimeters are also common.
To give you an idea, the price of a 244 × 122 16 mm thick card (the most common format) is priced at around € 16 (approx. € 5.34 / m2)
What is the density of particle boards?
The cards are sold in reasonably standard sizes and thicknesses. This is relevant with regard to density, since when making the card in small thicknesses, it receives a little more density to improve its resistance a little. Normally, as the thickness of the particle board increases, the density decreases.
- In thicknesses less than 10 mm, the density can be between 720-740 kg / m³.
- 10 mm is a very common thickness, used mainly for the interior of drawers and furniture bases. The average density of the agglomerate, in this case, will be 700 kg / m³.
- The most common thicknesses are 16 mm and 19 mm. In this case, the density is generally between 675-690 kg / m³.
- Between 25-30 mm, the density will be approximately between 650-670 kg / m³.
- From 30 mm, the density can drop to 640-650 kg / m³. It rarely falls below that level.
To give you an idea, woods like ash, oak or birch have this density, and others like fir or pine, much less. In this comparison with natural wood we speak only of weight by volume, in no case of resistance.
It is also worth mentioning that not all manufacturers offer exactly the same product. There may be differences in composition and therefore also in the density of chipboard panels.
The main use of the card is the manufacture of indoor furniture: modulation of kitchens, cabinets, dressers, shoe racks, shelves, office furniture …
Also interior carpentry such as doors, countertops
In waterproof and fireproof versions, its use extends to floor, wall and ceiling coverings, partitions.
Particleboard or MDF Which one is better?
As we mentioned at the beginning, chipboard and MDF (medium density fiber board) have become the standard in furniture making, replacing solid wood and other types of panels.
The two materials are similar, but there are differences that deserve to be highlighted to facilitate the choice of one or the other.
We already know that chipboard panels are mainly made of fragmented wood. MDF boards are also largely made of wood, but this time the wood breaks down into fibers, that is, much smaller particles.
The first implication of this difference is the quality of the board’s surface in terms of uniformity and texture. An MDF is much smoother and more uniform to the touch than a card, which means that when applying any finish (varnishes, enamels, lacquers …) the result will be much better.
MDF also has an advantage when we are facing machined with curve, for example, the outline of a frame or footer. Also against curves. Although MDF is somewhat malleable, the card breaks easily when curved.
They are substitutes, with very similar benefits, in the manufacture of furniture where straight lines predominate. In that case, the lower price of the card gives them a certain advantage.