Polystyrene

One Comment

1. BuildingMaterials.co.uk says:

   September 10, 2009 at 9:57 am

   There are two types of polystyrene sheets; expanded and extruded polystyrene insulation. Expanded polystyrene has a lower density than extruded and is also less expensive. However, because of its lower density, it has slightly lower insulation power. Extruded polystyrene insulation is denser and contains a mixture of air as well as gas, allowing it to trap more air particles, and making it a better insulator than expanded polystyrene.

   Extruded polystyrene also has more qualities which make it an excellent choice for insulation due to the way it is made. It starts as solid polystyrene crystals. These crystals are then combined with special materials and then melted. In a machine called an extruder, the temperature and pressure are controlled to change the crystals into a plastic fluid. This plastic is then forced into a mould, and upon emerging from the mould, it expands into foam as it cools which is then cut to specifications.

   Due to this method of creation, extruded polystyrene insulation has a smooth surface which can’t be duplicated with other forms of insulation. These qualities also allow it to be used for moulding into panels or blocks for wall thermal insulation in homes. The foam also allows easy cutting for electrical wires to be run through it. The gaps between the insulation can easily be filled with concrete which will make a grid of columns after it dries.

   Regarding the US view on the situation further information can be found at;
   http://www.fhwa.dot.gov/crt/lifecycle/geofoam.cfm