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Other stone floor with steel beams

Steel-girder sandwich floors, while innovative in design, present a hidden risk of rusting in damp environments, potentially leading to significant structural damage. Understanding the importance of proper ventilation and preventive maintenance is crucial to preserving the integrity of these floors, and a thorough inspection can reveal the true extent of any damage, offering solutions before the need for complete replacement arises.

A steel-girder sandwich floor is a system floor consisting of steel beams with concrete elements and a compression layer between them. A steel mesh is placed on top of the sandwich floor, which serves as reinforcement for the concrete poured on top (the compression layer). This compression layer is also called a cement screed. This type of floor can be visually inspected from below.

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Because this is a high-risk floor, the crawl space and the underside of the floor must be absolutely dry. The crawl space must also be properly ventilated. In many cases, a thorough inspection has revealed that rust on the steel beams may be present in limited quantities.

If the cement screed (compression floor) is damaged on the top, one possible cause could be rusting of the iron beam. Rusting materials expand in size and can develop enormous forces. This can certainly cause such damage and recur at some point after repair. Loose sections of the cement screed can be removed and repaired. The extent of the damage will only be clear after a thorough inspection and tapping of the concrete floor.

Steel beams in floors

If the steel beams rust, this can damage the cement screed , floor structure , facades, and walls in the house. If the rust is not too severe, preventative measures are still possible and can prevent worse from happening. We recommend removing the rust and treating the iron with red lead. After this, the entire structure can still function properly in a dry and well-ventilated crawl space.

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If the steel beams are severely rusted, this will damage the cement screed, floor structure, facades, and walls of the house. Repair will likely be virtually impossible; at some point, the entire floor will have to be replaced. If there's any point, we recommend removing as much rust as possible and treating the steel with red lead. Ensure the crawl space is well-ventilated; ventilation openings should be present at both the front and back of the crawl space.

Would you like to make an appointment for a building inspection?

The cost of a building inspection (up to 250 m²) is only €489 including VAT. We'll conduct a comprehensive building inspection and you'll receive a building report. Do you have any questions? We're happy to help and can schedule an appointment with an expert inspector right away if you wish!

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