Construction Informer

Ontario Eyes Mandatory Workers’ Comp: Claiming companies that don’t pay workers compensation insurance premiums have an unfair advantage in the marketplace, the Building and Construction Trades Council of Ontario is seeking to put a stop to that. The governmental body is introducing legislation that will make having workers compensation mandatory for those in the construction sector. The agency also says that by expanding the pool of participants the costs to all participants will go down. It is expected that 90,000 workers would be picked up on coverage.

Buildings on the Moon May Go Waterless: Take some lunar soil and add some sulphur and you are ready to pour, er, plop, some concrete down in the form of a building. A University of Alabama professor says the mixing of those two components means concrete could be made without water. Since any water that may be on the moon is in extremely limited supply, and moon dust is not, this makes for some wonderful building opportunities. 

Speaking of Concrete: The material is used the world over and is more and more popular for its formability and strength. But, because it is porous it allows moisture inside where it can corrode reinforcing steel and woven wire mesh. Now, researchers say you can use sodium acetate to make the concrete less permeable. But, where do you get sodium acetate? Why from potato chips of course. It is used to flavor them. This could give the meaning of “lunch break” a whole new slant.

Houses Built from Waste: A UK researcher is writing a recipe for a new material for building homes. This one uses recycled glass, metal slag, sewage sludge, incinerator ash, and pulverized fuel ash to make – you guessed it – building blocks. By binding the components together with bitumen the resulting bloc is six times stronger than a cement block, requires less energy to make, and is made of 100 percent waste material. I can see the instructions now: Combine ingredients in mixing bowl, form into a block and place in very hot oven for awhile. Makes 1 block. This could be on the market in the next five years. Of course great plans like these need great followups. Next they’re going to try blocks made with the help of used vegetable oil, and tentatively have thought about calling them – Vegeblocks.

What will they think of next?

The rush to green is already carrying with it the seeds of its destruction – green claims that don’t stand up under close scrutiny. For those in the construction industry there is a lot at stake.

When we build things we usually do it with the intention that they last a long time. All of the components taken together in a building make up the whole but if one, or a few of them don’t stand up to their claims of environmental friendliness, health and safety then the entire building is compromised. How can you certify the healthiness of a component that was only created a few years ago when it is expected to perform for many years? Where do you get the long-term data to back up its claims?

There is also the concept that you have to take into account the life cycle of a material when evaluating its greenness. Generally referred to as a life cycle assessment (LCA), and more technically as a life cycle inventory assessment (LCIA), it is an attempt to place a value on the environmental impact of a material. Is a petrochemical-based product really green just because it reduces a building’s energy use? What about the energy used to produce it, the toxins given off, and what about the environmental costs of disposing of it when its life is done?

But even the techniques used, and especially assumptions that are made when doing an LCA can be called into question. As one expert in sustainability, Arnold Tukker wrote to the Society of Environmental Toxicology and Chemistry (SETAC), a nonprofit professional society, regarding the SETAC’s efforts relating to an assessment model for chlorine, PVC and hazardous waste management:

Personally, I believe it will never be possible to solve controversial discussions about products with an LCIA method that is based solely on mathematical relations between interventions and protection areas. There are simply too many uncertainties, there is too much ignorance, and they can only be overcome by all kinds of subjective, subtle, and basically value-laden choices.

Someone could argue that lumber is not a green choice for building because its harvest aborts an element of CO2 absorption, removes habitat for other life, increases soil erosion, requires the burning of oil products in its harvest and milling, and finally doesn’t offer the benefits to the soil of its decay when its useful life is over because it is most often discarded in a landfill, or burned (in which case it adds CO2 to the atmosphere).

In years to come we will be hearing more and more about building materials that were once called green but didn’t stand the test of time. As smart as we are, we still don’t have the crystal ball and we still can’t truly predict the long-term effects of our actions. The best we can do is make informed judgements and not only recognize we don’t have all the answers, but be willing to admit it as well.

Makers of materials and products might consider toning down their green claims before people start finding out they are really only a little bit green.