Big Microscopic Changes.
A close look at some decking and foundations new to Canada

By Jon Eakes

When we talk about technology, we usually think about electronic gadgets or better tools, but now developments in what used to be simple deck boards are happening at the cellular level.

If you have studied wood moisture content and expansion and shrinkage of wood, you have already dabbled in the cellular level. Below 19% water content, wood is stable. Expansion or contraction of wood happens in the 19 to 28% water content range. What you may not have realized is that all of this water is bound up in the cells of the wood. Hold the board up and nothing drips out. Below 19%, water flows into the cell but does not change its size. As the cell becomes saturated, it will swell—or shrink if going from saturated down to dry. Above 30% the cells are saturated and all additional water fills in-between the cells and is called free water—and this water is free to feed mould. Water inside the cell is bound and not available for mould, which is why you can still have moisture in dried wood but it will not rot.

Moving from Outside Cells to Inside Cells
Traditional Pressure Treated Wood (CCA and ACQ) just shoved chemicals into the free water space and coated the cells to protect them. Micronized Copper Azole (MCA), better known as MicroPro, changed the game. They found a way to grind up copper (the C in all these formulations) so microscopically fine that it could physically pass through the pores of the wood cells to the centre of the cells of cellulose, pushed in by the Pressure treatment. Then when the drying stage was applied, there was no force to drive this copper back out of the cell, and the inner part of the wood cell now contained a copper power coating that would not leach out. This copper stops the mould and fungus cells in their tracks.
As it turns out, this is harder to do in Canadian timber than in Southern Yellow Pine and it took Timber Specialities a couple of more years to perfect the treatment. So although MicroPro wood has dominated American deck building for several years now, it is just coming into its own this spring in Canada, all of it with a brown stain by consumer demand. So when you see Goodfellow’s “Terra” wood, or Timber Specialties’ “MicroPro Sienna,” you are looking at the next generation of pressure-treated wood. No corrosion problems with fasteners, no problem with aluminum contact, no leaching: The copper is locked inside the cell, not in the free water space between the wood fibres. In fact, with NGBS Green Certification, EPP Environmentally Preferable Product and UL GREENGUARD GOLD certification for low VOC emissions, it can be used for children’s playsets and fresh water docks.

Removing the Skunk from End Cut
As you know, you need to treat all cut ends of any PTW product and if you haven’t figured it out yet, Timber Specialities “Cut-n-seal.com” end cut treatment is the best choice, not because you can get it in both green and brown, but because it doesn’t smell bad. It came onto the market right after I sent them a jacket splattered and reeking with end cut treatment that my wife refused to let me bring back into the house. I like to think I was responsible for low-odour end-cut treatment.

Petrifying The Cells

What happens when you don’t just dry the wood, but modify the properties at the same time? Kebony Wood is primarily Southern Yellow Pine that has been soaked in a bio-based alcohol and as it is cured and dried, a polymer is protecting the cell wall. As you see above, the cell walls themselves are thicker because they have been permanently swollen by the treatment. This makes this softwood almost as hard as Ipe Decking and it becomes less affected by moisture and hence a more dimensionally-stable wood. The process gives it a natural roasted brown colour that fades very slowly.

Kebony Wood was developed some time ago in Norway. Initial distribution has covered many kilometres of boardwalks in Norway, and now Canada, for the simple reasons of durability and freedom from maintenance. This wood does not need sealing, in fact a water-based sealant would just be repelled anyway, and there is nothing to gain by trying to pollute the wood with a solvent-based sealer. At end of life, you can burn this wood—no more hazard waste disposal.


Although more expensive than PTW 5/4 deck boards, it is competitive with all the speciality or exotic decking material available, especially when you consider that there is no staining and no sealing or resealing to do ever. With a 30-year warranty, walkways have lasted longer than that in Norway because you are never wearing off a protective coating—unless you walk your way all the way through the board.

Will the SCREW Dominate the AUGER?
I have written a great deal in this magazine about deck foundations and their evolution with and without concrete. Personally I really got sold on the auger foundation: a spiral plate welded to the bottom of a long shaft that would drill itself into the ground with little soil disruption and then sit deep in the soil as a footing for the metal column.

The company Postech engineers the blade size to match the soil conditions and load demand and their Thermal Screw Pile is specifically made for frost protection. Since I wrote about them two years ago, they have spread their franchises throughout Canada.
Now there is a different concept that has arrived in Canada out of success in Europe: a tapered screw that gets it support power by the cumulative surface of the thread on the screw and the fact that as it bores into the ground, its tapered shape compacts the soil laterally. It is every bit as easy, if not easier, to drive into place in most soils than an auger and gives considerably more load bearing.

The international leader is Krinner from Germany. It started out as a quick and solid way to install vast fields of solar panels, giving lateral, as well as vertical, support without concrete. In addition, the screws can be unscrewed from the ground and relocated if necessary. The ground screw has grown to support all types of temporary and small structures and now is even engineered to replace piles for support of commercial and residential buildings with typical lengths ranging from 3 to 7 feet (550mm to 2100mm). The Canadian distributor is www.aduvo.ca, a company specializing in modular container construction. Their smaller screws are perfect for deck construction.
When I asked the killer question: “What happens with frost heave and ad-freezing in clay soil?  It seems to me it would push up on this tapered screw thread with more power than the weight over it.” The answer was simple, gleaned from their experience in Northern Alberta. They make many different configurations of screws, some that go deeper than necessary for the load but with a smooth shaft that can go all the way through the frost layer with the supporting threads only down below the frost line.
Bayo-s.com is another screw-style foundation available in Canada fairly similar to Krinner but with fewer engineered variations, giving some competitive choice in this field new to Canada.

Montreal-based TV broadcaster, author, home renovation and tool expert Jon Eakes provides a tool feature in each edition of Home BUILDER. www.JonEakes.com

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