In addition to their aesthetic appeal, the use of raw materials can save resources by bypassing the use of additional coatings and processes. This type of solution was most commonly used in utility buildings, such as infrastructure, factories, and warehouses. Exposed concrete floors, for example, were primarily found in industrial spaces, parking lots, and gas stations. However, they are increasingly being used in structures of different programs due to their appearance, durability, resistance, and vast possibilities for finishes. But what are the main factors to be aware of when using a concrete floor for a project?
First, it is important that the designer takes into account factors such as the conditions of the terrain, the function of the space, the distribution of loads, and whether there will be exposure to agents that can corrode the concrete. To do so, it is essential that the relationship between water, sand, gravel, and cement in the concrete allows it to be finished with special machines after curing, bringing it to the desired strength and shade. It is also important that the service is well orchestrated and programmed, since it is usually done right after pouring the concrete of the slab itself.
After pouring the concrete, leveling the slab and ensuring proper density is important to eliminate trapped air bubbles, empty spaces, and excess water inside. The floor must also receive cuts for expansion in predefined areas in the project to avoid issues such as cracks when the structure expands and contracts naturally. It is only after the concrete has dried that polishing with special machines should be started. Depending on the process, it is possible to obtain a more or less polished finish. For future protection and a final finish, the application of a resin suitable for the specific use is recommended.
Although it is more common to maintain the natural tone of the concrete, which varies between light and dark gray and contains characteristic stains, there are also opportunities to add pigments to the mixture and achieve different shades.
The most common concrete floors are those armed with wire mesh. Currently, there are also options in the market for floors with metallic and polypropylene fibers that reduce concrete shrinkage and, consequently, the resulting cracks. There are also options with prestressing systems of steel strands, tensioned inside the floor, allowing the execution of floors without expansion joints.
See below a selection of projects with exposed concrete floors:
Center for Interpretation of The Battle of Atoleiros / Gonçalo Byrne Arquitectos, Lda. + Oficina Ideias em linha – Arquitectura e Design, Lda.
Proofread by Lilly Cao