Resources
History of Wood Restoration
Wood has been used as an article of construction since before the dawn of civilization. One of the earliest methods of increasing the durability or longevity of wood was fire, hardening the tip of a wooden spear or arrow. This caused the resins in the wood to harden giving a stronger, more durable point that more efficiently pierced simple leather armour and gave an efficient kill to game animals. This process also sterilized the wood, which was important since the variations of fungi that eat wood are many and common on the planet.
Some varieties of wood also contain natural antibiotics and these, when present, help to give wood longer life by giving resistance to the micro-organisms that regard wood as food. Wood used for weapons or other utilitarian articles tended to wear out before it rotted, while wood used for construction tended to rot before it wore out. In relative terms, wood wore out quickly but rotted slowly.
Wood used for architectural purposes only exhibited long life under extremely cold conditions or when in an oxygen-free environment, as the micro-organisms which feed on wood require oxygen. The air contains about twenty percent oxygen.
Hundreds of years old wooden ships which were buried in mud have been found, and wooden ships and buildings hundreds of years old and in very good condition have been found in arctic climates such as Alaska and northern Canada. It is possible that the fabled Ark of Noah, several thousand years old, has been entombed in ice on Mount Ararat in Turkey.
When wood was used at temperatures where fungi and bacteria are active, the only known technology of "restoration" was to cut out the deteriorated area and glue in a fitted replacement portion. In ship repair, in the last hundred years, the insert was known as a "dutchman". For general repair and preservation hot tar might be used. While creating a somewhat waterproof seal with little physical strength, hot tar tended to sterilize the wood and this plus the tendency to seal the wood from the air at the location where the hot tar might be applied, contributed to the longevity of this technology. The Indians of the North American continent used tar as a sealant for birch bark canoes.
Tar or Pine pitch or a mixture was commonly used as a sealing compound between the deck panks of wooden ships hundreds of years ago. The material was heated and poured into the seams where it solidified. The decks were thus sealed against water and rain leaking through to the cabins below.
The surface protection of wood was accomplished by treatment with oils of various beans, berries or seeds which had been found to dry and harden on exposure to the air. This material today is what we call varnish. Joints between separate pieces of wood on older boats were usually filled with a paste of fibrous materials, lead oxide, and various vegetable oils or varnishes. The lead oxide served as a primitive fungicide to deter the rot which would begin when the inevitable fungus spores, carried by air or water, got into the space between two pieces of wood and proceeded to hatch, grow and eat the wood.
The marine environment is hundreds of times more severe than the architectural environment, in terms of both dampness and mechanical stress. Technology was thus forced to develop for marine maintenance and restoration, where little technology was forced to develop for architectural maintenance and restoration.
The Dawn of Contemporary Wood Restoration
In the 1950's Shell Chemical Company invented a commercial process for manufacturing a type of resin (which they called "epoxy" for technical reasons) and a variety of curing agents for it. The family of adhesives and coatings which were developed from these products turned out to be surprisingly versatile and compatible with a wide range of wood, metal and concrete materials. The U.S. Department of Defence rapidly developed improved versions of these paints and adhesives in their own research laboratories, to meet a wide range of military applications.
Many large and small companies began to make "commercialized" or lower-cost versions of military formulations and to offer them to industry and the general public for just about any possible application, with no serious application technology. By the late 1960's - 1970's many small business had developed architectural maintenance products which were moderately successful, although a common failure mechanism was that some one to a few years later an epoxy filler in the wood might be seen to come loose and rise up under a coat of paint, or rot to start up again behind a spot that had been "treated" with some "restoration" product. These architectural maintenance products could not cross over successfully into the marine market place as the quality of restoration possible in the architectural market was such that with luck a repair might last five or ten years; in a marine environment that same quality of repair might last three months to two years. The technology was not viable in the more severe marine environment and only barely viable in the architectural environment.
THUS, THERE WERE NO EPOXY RESTORATION PRODUCTS SUCCESSFUL AND EXPANDING IN EITHER THE MARINE OR ARCHITECTURAL MARKET PLACE.
In 1972 Steve Smith became aware of the need for something to handle deteriorated wood on boats from a friend in the marine business. The base for what CPES is now was created and asked his friend to try it. The short term results were so successful that a demand appeared almost overnight.
Meanwhile, the technology was evolving and becoming optimized and more refined as the actual needs of the end users became better understood. Various painting contractors and remodelling contractors had begun to use the product for routine maintenance and restoration. The State of California State Architect office and the Department of Parks and Recreation found out about the products, evaluated them and began to use them for the restoration of various historic structures.
A boat builder who happened to be working for the U.S. Government, stationed on the Kwajalein Atoll in the South Pacific (part of the Pacific Missile Test Range), found that the Clear Penetrating Epoxy Sealer was useful in the maintenance of the wood buildings on Kwajalein which housed the radar and electronics gear. Thereafter anywhere from thirty to two hundred gallons every few months were sold to the U.S Government and shipped to Kwajalein for continuing restorations of the wood buildings. This is significant because Kwajalein is hot, humid, and gets about a hundred inches a year of rainfall. The product was successful in maintaining, old and new wood buildings that, before this time, were simply torn down and replace every few years. This continued through the end of the Cold War and the closure of the Pacific Missile Test Range in the early 90's. The radar station is now used as a mid-Pacific air traffic flight control center, and the use of this product continues.
THUS, ONCE A VIABLE TECHNOLOGY FOR THE RESTORATION OF DETERIORATED WOOD IN A MARINE ENVIRONMENT WAS DEVELOPED, IT SPREAD AND EXPANDED RAPIDLY IN THE ARCHITECTURAL MAINTENACE MARKET PLACE SINCE IT WAS AN INHERENTLY VIABLE TECHNOLOGY.
The Modern Technology that Restores Deteriorated Wood
The technology underwent significant refinements in the laboratory in the late 80's and early 90's but none of this was released to the public since it was felt that a better customer training program would be needed to take best advantage of the latest refinements. The present customers had learned about the products through word-of-mouth or some limited advertising, and the only training possible for mail-order customers was the enclosed literature package.
The technology had gained great acceptance among end users, including some pest control operators who used the product to restore deteriorated wood despite written rules from their regulatory agency stating deteriorated wood must be removed. The technology did not have a theoretically derived origin but rather a experimental one. Thus, no authorities in the Forest Science Departments of Universities had evaluated the product and measured the properties of restored wood and certified that some percentage of restoration could be reproducibility achieved and measured under standard test conditions. This is in fact impossible, since there is no such thing as a standard piece of rotten wood.
Thus, no restoration standard was possible. City building inspectors were now commonly coming into contact with the products and their use in a variety of circumstances and more questions arose, as restoration of deteriorated wood is not covered by any building code. Yet, people were using it and it seemed to work, the test being to jab the wood with an ice pick to assess the state of deterioration by the degree of penetration. After treatment with the Clear Penetrating Epoxy Sealer, the treated wood resisted penetration by an ice pick in similar manner that new wood did. Thus, restoration was accomplished in fact if not in law.
The Future of the Restoration of Deteriorated Wood
The development of professional versions of these products has now been accomplished, based on the knowledge gained and refinements and field tests and evaluation of the last 24 years. The trademark Lignu was created and registered to denote the modern, high-performance family of wood restoration products. A training concept for a limited customer base of professional users has been devised. Thus, the first barriers to mass distribution of the technology and its products have been removed.
Wood is commonly used in construction, has been for hundreds of years and will certainly continue to be for hundreds of years due to the low cost and high production rate of wood by the natural vegetable life forms of this planet. Since the technology relies on restoration of deteriorated wood using, in great part, material actually derived from wood, it is expected that these products and this technology will persist as long as wood itself is used in architectural construction.
