How much does it cost per square meter?

"How much does it cost per square meter?"

Ita, 45 y.o, Property Owner

The above question is very often (almost always) expressed on a light steel roof truss salesman. Most salesmen usually immediately mention the price per m2 with ease. But who has experience in the field of roof truss will not be as easy to answer or call the price of lightweight steel roof truss in m2. Why? Let’s see why.

In contrast to roof coverings or roof tiles that can be calculated per m2 of roof incline, the shape of the truss on a lightweight steel roof truss consists of a variety of materials, depending on the structure calculations. The structural determinants include the weight of the roof covering material (tile, shingle, metal sheet, etc.), the ceiling load (along with the hanger), the span of the horses (the pedestal to the pedestal), the angle of the roof and of course the shape of the roof (jurai, saddle, single slope, etc.).

The following two case examples will help explain why the price of lightweight steel roof trusses can not actually be calculated per square meter of the building. Figure 1 shows two different buildings, but has the same plane area of 100 m2. Suppose the angle of the roof is both 30 °, then the area of the roof incline (roof area) both remain the same, ie = 100 m2 / Cos 30 ° = 115.47 m2. We assume also the roof cover load, ceiling, and others are considered equal.

When calculated correctly (using software and using materials with exact strength specifications as calculated by the software), lightweight steel roof truss for House B would be cheaper price per m2 compared to House A. This is because the span of the horses (truss span ) for House A is 10 meters, while Rumah B is only 5 meters. With smaller horses, the profile may be smaller. In addition, the mounting factor of the horses is also influential, where the installation of small horses is also easier, so the wage mounting can be suppressed.

When calculated correctly (using software and using materials with exact strength specifications as calculated by the software), lightweight steel roof truss for House B would be cheaper price per m2 compared to House A. This is because the span of the horses (truss span ) for House A is 10 meters, while Rumah B is only 5 meters. With smaller horses, the profile may be smaller. In addition, the mounting factor of the horses is also influential, where the installation of small horses is also easier, so the wage mounting can be suppressed.

Meanwhile Figure 2 illustrates the shape of the roof with different angle of inclination. House C has a roof inclination angle of 30 ° (thirty degrees) while House D is angled roof 45 °. We assume the loads supported by both roofs are the same. The price per m2 of roof slope for House D is definitely more expensive than Rumah C, because the material for roof frame structure is much more than House C.

The same thing happens with the weight of roof cover material to the price per m2 of roof truss. When using ceramic or concrete roof tiles that weigh about 40-50 kg per m2, of course the cost required to make lightweight steel roof truss is more expensive than if using metal tiles that are only about 7-8 kg per m2. So if there are two roofs that shape, size, stretch of horses and the exact same slope but different types of roof coverings, then the price per m2 will also be different.

In conclusion, if you want to calculate the cost of lightweight steel roof truss, just entrust it to the supplier or seller of lightweight steel roof truss that has good structural calculations, and has a good reputation.