In response to pressures on existing construction materials and practices, there has been increasing interest in cellulose composites. It is becoming evident that new types of building materials have the potential to make buildings which offer lower operating costs and increased durability in an environmentally friendly way.
On a per project basis, these new materials are available for construction projects at rates which are competitive with conventional materials. The materials are part of a project management service which assists clients to reach their goals in constructing the building.
Construction Technologies, a Calgary, Alberta, Canada company has been working on cellulose composite building materials since 1990 and has now developed prototype materials using locally grown industrial hemp and flax, and crop residue fibers. Cellulose becomes extremely fire resistant when combined with mineral binders in the proprietary composites developed by the company.
With cellulose composites, it is possible to design the structural and insulating qualities, the heat retaining qualities to suit climate and strength needs. Building components such as walls, roof and floors may be poured in place or moulded for later use.
The designs which accompany the material are monolithic, one piece, of- a-thickness panels and components and vary in density as required. Plans are to produce a prototype which will demonstrate an interior partition wall system and the structural use of thick panels in floor, roof and wall in a prototype building. The principal in the company, Geoffrey Lyford, has project manager and craftsman with about 23 years experience in many phases of construction. Since 1990 he has been involved with modern versions of ancient building technologies such as rammed earth and cellulose composites. Most recently the company developed a panelized concrete building system in conjunction with another technology company. Previously, the company consulted in manufacturing stress skin or structural insulating panels (SIP), erecting the first completely SIP prototype in Alberta, Canada.
A unique and exclusive approach to understanding the origins of materials forms the basis of Construction Technologies product development: that is the blending of modern high production capability with ancient ways of deriving materials from the environment.
Ancient ways are good ways when it comes to sustainable construction. Traditional builders take local natural resources and use them well. The challenge has been to take ancient materials and create ways to produce high volumes of modern housing with the considerable technology we have at our disposal at this very moment.
It was important to take stock in the physical environment, but to say in an elementary way – minerals are most abundant, cellulose from plants second most abundant. Can a house be made with dirt? Can a house be made with fibers or sticks? How do combinations of minerals and cellulose work? What are all the ways this has been done. How did the ancients do this? What are the qualities of each and how do they affect materials for construction?
It became clear that minerals offer structural compressive strength and heat retaining qualities, while cellulose tends toward structural tensile strength and insulating qualities. It also became clear that the materials and the designs complement each other. It was not enough just to develop a new stud to put into an old wall, but take a fresh look at how the materials could be used in new/old ways and to use the shapes of components to give strength.
This vision of housing takes the best of the ancient materials, improves the processing and ingredients of materials for durability, function and strength, and derives methods of high production at low cost. Why not combine the best of both and achieve a synthesis greater than the parts. Work began on a low tech level, while the strength and durability of the materials and coatings has gradually improved. Even the first materials had exciting properties of insulation and heat retention, and they combine the attributes of wood and ceramics.
The latest cellulose composite materials contain minerals and binders as well, but are lighter and of higher strength. We expect to have a new batch of materials and test results available soon.
In growing plants, lignins occur naturally with cellulose. Some manufacturing processes use these natural binders to form products such as straw board, or cast hemp. On the mineral side, several promising minerals react favorably with each other and with cellulose. These areas currently occupy investigation for application in cellulose composites.
Modern housing standards in some ways lack the self-sufficiency of the old, but we are coming around to that point again where a house must look after itself without extra energy input other than sun and wind for heat or cooling. And modern technologies have given us the belief that we can build self-sufficiently.
Life cycle accounting for housing costs are another way of seeing a more holistic picture. How much financial input, energy input is required for the life of the structure, in maintenance, heating, cooling. How long will the structure last.
Ancient cultures existed for hundreds, perhaps thousands of years. They relied on materials from their environment to create wealth. We can look at how they took raw materials and created shelter. Our Product Development combines traditional materials with modern technology.