Every now and then we have a client that wants us to build a house and then in the process use product this or that for the purpose of finising the roof, or insulating the walls, or whatever. Usually product “this or that” is supposed to somehow lower the maintenance cost of the new house. For instance: composite materials for covering outside walls.
Alternatives For Wall Cladding And Roof Tiling
Many years ago products based on asbestos were popular for roof tiling and wall cladding. We all know how that one ended, and today it is very difficult to get rid of the stuff without hiring guys in white astronaut suits. In The Netherland we recently had a client who almost landed himself in jail for a weekend when he tried to get rid of 1 m2 of asbestos flooring from his old house, without hiring the astronaut-brigade. We all had to laugh about his story, but still it is a serious environmental offense.
These days we see products based on a combination of recycled wood and plastic. The manufacturers promise i) no need to seal or paint, ii) no rot, iii) no splinters, iv) UV colour stability and v) the list goes on and on.
We admit, some of these products don’t even look half bad. But we have never ever seen such products that still look fine after twenty years. So we use larch instead. Ages nicely and looks good after sixty years. Maintenance? What maintenance?
Polyurethanes, Polyethylenes, Polystyrenes
Nope! Well ok, we may use a little polyurethane here and there to close a small gap between a log and the foundation, but mostly we try to avoid it. These products are not re-usable, are not damp-open and end their lives as chemical waste.
We want damp-open. No way we will use polyurethanes, polyethylenes or polystyrenes as the main insulation material for a wall or a roof.
There are discussions in the industry about the possible long term health hazards of glasswool. You will find studies and reports everywhere on the internet, some financed by the industry that tell is there is no problem, while others that are financed or sponsored by governments also tell us there is no problem. Problem solved, no?
But the rumours persist, and honestly we don’t know what to think of these rumours, we’re not specialists. We don’t like rumours, but on the other hand glasswool is just a molten and solidified anorganic material, and we don’t understand why we should be worried.
We must be a little pragmatic sometimes. We are not extreme eco-activists and so we use it, but at the same time we prefer rockwool over glasswool and actually we prefer wood fiber and cellulose even better as these products are not at the center of a health hazard rumour and also they have a much higher thermal mass and temperature stability.