Sunday, September 21, 2008

I think steel is the way to go for the best closed loop in construction materials. A majority of structural steel is from recycled scrap without compromising the strength of the material.
Concrete consumes so much material for its construction (cement, water, aggregate, steel, wood, formwork) and its reusage is low percentage from its original product. This does not really create a well closed loop.
the same goes for wood also, since reusage of the wood cannot create as well as steel in the original product. Glulam helps, but with wood, it seems all you can do is mitigate your consumption as well as being more efficient with milling. This does not really create a well closed loop.
Steel is not the perfect answer, with the demand of steel construction and building lifespan not correlating, it is the best of the three, I believe. Hopefully, in the future, more questions will be asked or answers be revealed to create a closed loop system either ameliorated conventional supplies, or new materials will be introduced.


Justin Smith said...

Paul said...

The fact that steel can be recycled so easily does lend well to a closed loop system, but the origin of steel prevents it from being 100 percent closed since it comes from a non-renewable resource (ore). Maybe they can just use less to make more...somehow.