We’ve begun to use tricoya in our Petflaps to replace about 80% of the acrylic we use. We have been looking for a replacement for a while, and tricoya came to our attention at about the same time that acrylic became hard to source, so it was an obvious move for us. Acrylic has become hard to source due to its use in Covid-19 protection measures, such as screens.

What is tricoya?

Section showing the laser cut edge of tricoya

Tricoya is a form of MDF that uses accoya is its starting point. Accoya is a sustainable treated softwood. Board made from an accoya base is far more stable, long-lasting and moisture-resistant than standard MDF. This makes it ideal for use in a Petflap. Petflaps are exposed to all sorts of weather, so the durability and moisture-resistance of this particular type of board was essential to us. It is insulating, making the Petflap an even better choice for a low-energy or passivhaus build.

We’re looking at using tricoya to make our new Letterplate Eco. This will provide a draughtproof and insulated barrier to draughts through your letter box.

How are we using it?

We are using tricoya to replace the acrylic ‘filling in the sandwich’ between the ABS outer frames. This means you’ll see what looks like wood on the edges of the open flap, and in the rim of the frame. In both cases, this is visible only when the Petflap is being used and the flap opens. Eventually we expect to make entire Petflaps from tricoya, ditching plastic altogether. Petflaps made this way can be sprayed or painted to match your  decor.

For the time being we will use our stock of acrylic to make the peep holes in the Petflap. Tricoya’s great stuff but it’s not yet made see-through! When our acrylic is all finished we expect to replace it with toughened glass.


According to,

“The trees selected to make Accoya are sourced from fast growing, abundantly available sustainably certified forests.”

It is a carbon capture product. At the end of its life, this board will degrade completely. It is a non-toxic product so releases nothing harmful into the environment.