Experiences of building IQbloc
Builder’s notes on the advantages of using IQbloc in place of Concrete blocks
The use of IQblocs, expanded polystyrene blocks in buildings has significant positive aspects compared to the use of concrete blocks.
1. Thermal and acoustic insulation capacity
With IQbloc’s double 4,5 cm thick walls they ensure remarkable thermo-acoustic performances.
In fact, in constructions made of concrete blocks (in particular for the external walls), in order to obtain a good thermal insulation, it is necessary to create a so-called “external” coverage, since the concrete only has a poor thermal and acoustic insulation capacity.
This obviously implies an additional cost for concrete blocks.
2. Speed of execution
The construction time of an IQbloc wall is reduced by more than 30% compared to the time for the concrete blocks wall, thanks to IQbloc’s lightness and the interlocking system between the various blocks that allows workers to proceed quickly with related physical efforts.
Needless to say, this time saving has a significant impact on the final construction costs.
3. Absolute coplanarity of the wall
The IQblocs, thanks to the interlocking system between them, allows a perfect coplanarity without any misalignments between the blocks that will produce very ugly corrugations to the plaster.
The plaster will then be placed on a perfectly smooth surface, facilitating the work of the plasterer and obtaining a perfect visual result.
The thickness of the plaster, finding a perfectly smooth surface, can be reduced to a minimum.
4. Structural consistency
Given the fact that in Malta there is no anti-seismic regulation and the structures are calculated only for vertical loads, however living in a building that has anti-seismic characteristics is always a positive fact.
The structures of the buildings, for the load-bearing walls, are made of concrete blocks 23 cm thick, filled with concrete and reinforced with vertical irons of variable section; while the internal partitions are made with blocks, always in concrete, with a thickness of 18 cm.
Let’s make a first consideration:
a square meter of 22 cm IQbloc wall, contains within it an amount of concrete equal to 0.11 m³ and therefore has a weight per square meter of: 0.11 x 2.250 kg/m³ = 247.50 kg/m²
The weight of polystyrene is neglected as it is absolutely insignificant.
The wall with concrete blocks contains within them, per square meter, 0.15 m³ of concrete for a weight therefore of:
0.15 x 2.250 kg/m³ = 337.50 kg/m²
To this weight you have to add that of the blocks: you need 9 blocks to make a square meter of wall and weighing a
block (simple density) 29 kg, the total weight of the blocks per square meter of wall: 29 kg x n° 9 = 261.00 kg/m²
which added to the weight of the concrete: kg/m² 337.50 + 261.00 kg/m² = 598.20 kg/m²
So the entire structure is much lighter and another important factor is the homogeneity of all the vertical elements, the IQbloc walls. Both the 22 cm and the 18 cm thick IQbloc walls are filled with concrete and reinforced in the same way, unlike the concrete block walls, where some are empty, others filled with concrete, others with concrete and iron. Obviously concrete block walls diversity depends on the stresses that are required on them, but this induces different behaviors.
The IQbloc walls, in addition to having a behavior that is certainly more homogeneous to the various stresses, fit together without interruption, forming a coherent framework with the floors and roofs, absolutely rigid, all collaborating together with the resistance.
In conclusion, it can be said that structures with IQbloc walls, although not specifically calculated for the horizontal thrusts caused by the earthquake, have an absolutely higher seismic resistance than structures in concrete blocks.