Cost factor floor plate - these costs are per m²
- Cost and construction of a floor slab
- The concrete pump
- The plate foundation
- Cost savings
- Possible personal contribution
If there is a component that can not be saved, it is the bottom plate. It forms the foundation on which the rest of the building stands. Savings on material, tools or design can therefore have fatal consequences, as a repair to the foundation is feasible only by massive demolition measures. That's why it's better to do everything right the first time. This saves considerable follow-up costs and gives the secure feeling of having built on a solid foundation.
The bottom plate is a continuous and homogeneous layer of reinforced concrete. What is represented on the upper edge as an even surface. It consists of many different materials inside and at the bottom. Even statically, the bottom plate is by no means homogeneous: the bottom plate in turn rests on the strip foundations . Although you can no longer see them on the cast floor slab, the structure may only run along the foundations. Highest precision when measuring, excavating and boarding the floor slab is therefore the top priority. Subsequent postponing of foundations is impossible. Although a base plate technically difficult to implement. However, a high level of knowledge in material science and construction is necessary. A DIY should therefore be well considered.
Cost and construction of a floor slab
A floor slab for a garden shed or terrace with a thin layer of concrete and a mild steel mat done. However, as soon as the base plate is to be loaded statically and thermally, a comprehensive mix of materials is required. This includes:
- Concrete in the quality of at least C25 - 127 to 159 euros per m³ of ready-mixed concrete
- Extensive reinforcement - 70 euros - 220 euros per mat
- Pressure-resistant rigid foam panels - 10 euros per square meter
- Formwork material - 10 Euro per m³ (the formwork, not the whole board!)
- Plastic film of at least 150μm thickness - 0.4 Euro per m²
- div. Drainage pipes, grounding cable, connection material
With an average thickness of 40 cm for the base plate, this results in a price per square meter of about 120 - 150 euros .
Invoice material costs
63, 50 Euro (concrete) +10 Euro (mild steel, mat only) +10 Euro ((hard foam board) + 0, 4 Euro (foil) = 84 Euro .
Including the cost of formwork, drainage and various additional materials, this results in a price of about 120 - 150 euros per square meter.
There are providers who quote prices of 70 euros per square meter. This is as unrealistic as dubious.
The abandonment of an insulation and a barrier foil is an unforgivable mistake. This creates permanent moisture with mold and frost damage in the house. This should be avoided at all costs.
To the material costs are still the costs for the construction and the introduction of the concrete.
- Costs for the soil survey: 500 to 1000 euros
- Transport and installation of the concrete: approx. 500 to 1000 euros, if a concrete pump is necessary.
The soil survey is indispensable for the calculation of the house construction. Usually, it is called by the building authorities before construction starts and creates the necessary security for the entire construction project.
The concrete pump
The concrete pump is ideal for the spreading of ready-mixed concrete. Especially when there are obstacles between the road and the concreting site, the concrete pump is usually indispensable. The price for the concrete pump depends on the mast height of the machine and the duration of the rental or the filled amount. The longer the pump is rented and the more concrete that needs to be filled, the cheaper the price per cubic meter of concrete pumped. It is therefore worthwhile to communicate with neighbors, if concreting work is also planned there. Typical prices for concrete pumps are:
- Mast height 25 m: at least 8.75 Euro / m³ to 7.40 Euro / m³
- Mast height 42 m: at least 12, 85 Euro / m³ to 11, 40 Euro / m³
- Mast height 58m: at least 23.50 Euro / m³ to 18 Euro / m³
With purchase quantities from 25.5 to over 300 m³ of concrete. The minimum billing amount is set at 25m³ for most providers. If you have calculated the mast height and the required range of the concrete pump as accurately as possible, you should still choose the number one larger concrete pump. It is much cheaper to pay a few hundred euros more for a concrete pump that is too big than having to stop work because the height and reach are not enough. When sizing the concrete pump, for example, you often forget the chimney on the roof or the cantilever from a balcony.
A total of 150-200 euros per square meter of floor slab is a realistic guide. However, these prices are only for the bottom plate.
The plate foundation
Another way of founding a house is the foundation of the slab. Although this looks in the end the same as the bottom plate, but has a decisive difference: It is uniformly thick. Slab foundations are used in poorly supported soil. It consists of a solid and particularly heavily reinforced plate with the same thickness. As a result, all incoming compressive loads are distributed over a larger area than in the strip foundations under the normal base plate.
Although they are easier to build than floor slabs, slab foundations are considerably more expensive due to the higher material requirements. However, they allow a greater scope for the superstructure, since they have the same capacity at each point.
As with all construction work, it is tempting to reduce costs through own contribution. However, it takes a lot of experience not to make mistakes when building this important component. For example, anyone who is confident can rent a digger themselves and take over the excavation themselves. But the hourly rent of the excavator continues even if the work has to be interrupted because of a severed ground power cable or a damaged water pipe. Until the dedicated self-builder has repaired the damage, the savings compared to the commitment of an entrepreneur disappeared again.
Loungers guarantee no power cables or water pipes in the area of the foundation, the builder can dare to self-experiment. If a base plate and no plate foundation are to be installed, however, two excavators are usually necessary. A medium-sized excavator takes over the Auskoffern of the area (or if desired, the cellar) and a mini excavator is used to dig the narrow strip foundations. The rental prices start at about 100 euros per day for a mini excavator. The price applies to most providers from place. The transport is the responsibility of the renter or must be booked separately. With a medium-sized excavator, more than 200 euros can be due for transport to and from the airport alone.
Unless the base plate is to be concreted for a carport, terrace or garage, it is impossible to concrete by hand. It is not technically feasible to produce several cubic meters of concrete for a house foundation with a mixing machine. The concrete simply binds too quickly to produce an equally thick and uniformly hardened layer. For filling a foundation with a base plate ready-mixed concrete is without alternative.
Possible personal contribution
But what a home improvement can do in-house, is the cleanliness layer. This layer is not necessarily a prescription, but makes every other step considerably easier.
- creates a uniform surface
- Prevents slush formation
- creates a clean surface for foils, insulation and reinforcement
- gives you the opportunity to quickly pump dry a full excavation pit again
- is very cheap
If you want to bring in the cleanliness layer yourself, the most economical lean concrete can be used. Instead of a mixing ratio of 1 part of cement to 4 parts of gravel, which is necessary for normal concrete, lean concrete is mixed in the ratio 1: 8. From a bag of Portland cement of 3 euros per 25 kilograms you can win twice as much concrete. The concrete is only applied with a maximum thickness of 5 cm and not reinforced. So you can bring 20 m² area with a cubic meter of lean concrete as a cleanliness layer. You can do that with a mixing machine.
However, a call to the concrete supplier can significantly reduce the trouble of self-mixing. Transport concrete operators often have leftovers in the car, which they have to quickly get rid of after mixing. So you can easily get completely free of charge to the concrete for its cleanliness layer. However, it is important to measure exactly how much concrete is needed. Much does not help much in the case of the layer of cleanliness, but the thicknesses should be kept. However, the type of concrete delivered is completely irrelevant to the cleanliness layer. However, this solution is only advisable if the further construction is not critical in terms of time. Here's an insider tip: The most concreted day is Friday. The probability of getting low-cost ready-mixed concrete is then highest.
Tips for quick readers
- Speed comes before thriftiness, so as much as possible left to the professionals
- Calculate concrete requirements exactly
- Concrete pumps overdimension a number
- Do not forget the water barrier and thermal insulation
- Cleanliness layer makes the work considerably easier and can be installed by yourself
- Requesting free concrete for a cleanliness layer saves a lot of work and costs