Concrete exists for more than 2000 years.
It is the material used to form the mass core of the resulting wall and can withstand floodings, earthquakes and tornados better than all other material.
Concrete is the most robust versatile material
that can be used in construction. It is the most widely used man made material in the world. It was first utilized by the Romans and was used to construct the famous Colosseum.
Styrostones/PIF/ICF are produced with the provision for a concrete core of 150mm or 200mm. In fact, for 95% of all houses in Europe a concrete wall with a width of 150mm are sufficient.
Pumping concrete is a fast way to build a very solid home The concrete is placed into the styrostones using a concrete pump. Most pumps are supplied with a 75mm reducer to restrict the flow of concrete into the formwork. This assists in the trouble free placement of the material. An experienced pump man should however be employed to carry out this task and your pump provider will always have a name to help here.
The concrete is of a specialist free flowing design mix and should be poured concentrically around the building to ensure equal pressure within the formwork. Normally the concrete is poured a couple of blocks high continuing around the entire building. It is advisable to have a man watching the pour as a safety check whilst the pour proceeds. When all of the walls are filled, their alignment should once again be verified for plumpness.
The strength of concrete used to fill the system is determined by the loadings that will be imposed on the walls. Usually the concrete specified for a domestic property is C 25 or 250kg/cm2. Considering that an average family home of floor space 140m2 will be subject to loadings of 5-7kg/m2 there is a lot of comfort in the safety factor compared to that of a timber framed building.