Timber Treated Piling

Alan Maling of Kardon Marketing Services has had over thirty years experience in timber piling applications and can advise on the best product for individual situations.

Kardon Marketing Services offers both softwood and hardwood treated timber foundation and marine piling. Treated timber piles are durable, strong and economical.

Not only are treated timber foundation piles resistant to decay and termite attack but also to chemically reactive soils that can attack steel and concrete piles. In marine applications as used on jetties, wharves, retaining walls, fenders and mooring piles, correctly treated timber piles offer long term, low maintenance performance.

Foundation piles are supplied in hardwood with safe end bearing capacities ranging from 360 kN to 1970 kN and in single length from 6 metres to 23 metres. Softwood piles are supplied with safe end bearing capacities ranging from 82 kN to 412 kN and in lengths up to 6 metres.

TIMBER PILE SAFE LOAD CAPACITY IN END BEARING (kN)

HARDWOOD FOUNDATION PILES

SOFTWOOD FOUNDATION PILES

LIFE EXPECTANCY – TREATED TIMBER FOUNDATION PILING.

The most commonly asked question about pressure impregnated timber foundation piling is:-

“HOW LONG WILL IT LAST ?”

This question is also one of the most difficult to answer. If the product is correctly treated, correctly installed, cut-off below ground line, coated with CN Timber Emulsion and capped, the foundation should outlast the life of the structure it supports many times over.

It is interesting to note that up until about 1900, practically all piling was timber and virtually none was preservative treated. History records innumerable examples of structures standing thousands of years on untreated timber piling. It seems ironical that the material which has proven itself is only questioned when alternatives without such a history are available.

In his paper to the American Wood Preserves Institute, Annual Meeting, December 1982, Bruce Haldeman, P.E. Divisional Engineer, produced a brief history of timber pilings and I quote a few extracts:-

  1. At Ephesus in what is now Western Turkey, a great temple was constructed around 600 BC and reconstructed 300 years later on the original untreated timber piled foundations.
  2. Near Rochester, England, excavations of old Roman roads revealed timber piles 1900 years old in first class condition.
  3. The first masonry London Bridge built in 1176 stood on untreated elm piles and lasted 600 years.
  4. The Campanile Tower in Venice was rebuilt in 1902 on the original 1000 years old timber piles, which supported the original structure built in 900 AD. Deterioration of untreated timber piles has occurred where water table fluctuation has allowed decay to develop.

This is not a consideration with correctly treated timber piling. Pressure treated timber piling is well known to withstand not only the agencies capable of destroying timber but also to withstand highly aggressive chemical soil conditions which can destroy both steel and concrete piling.

Today in the United States of America where treated timber piling continues to be one of the most commonly employed foundation systems, a conservative life expectancy of 100 years is the accepted normal.

The comparison in performance of the two pile types is dramatic.

Marine Borer Damaged

Turpentine pile at the marina

Photo taken Dec. 1993

Age 25 years

Unattacked

Double treated pile at the marina

Photo taken Dec. 1993

Age 21 years