We advise how to repair a floor that has been flooded. The sight of a parquet floor covered with a layer of water is not pleasant. The water is no longer coming in, so you need to collect the residue, dry everything out, and then repair the damage to the floor.

The most common cause of a flooded floor is a water system failure or something else. But just as much damage can be caused by water leaking from a broken dishwasher or washing machine. Repairing a flooded floor can take months. Here’s some basic information that may be helpful for proper wood floor repair.

Water on a varnished and oiled floor

Pick up spilled water on your wood floor as soon as possible. A small amount of water left on a sealed lacquered surface for 8 hours will not leave a mark. In a similar situation, an oiled board will create a trace around the perimeter of the puddle within 30 minutes, indicating that water has penetrated the wood. After 45 minutes, this trace is already very strong. An oiled floor is more sensitive to water because the oil does not close the pores of the wood, nor does it form a dense coating. Similarly, it will be the result of pouring a bucket of water, spilling water from the washing machine or dishwasher. If you remove water from the surface of a wooden floor very quickly, you can expect to see no marks or deformations. After removing the water, it is worth spreading paper towels across the floor and thoroughly drying the surface with them.

Water under the floor

If water covers the floor for a long time, it will be ruined. In addition, if the floor is completely flooded, which lasts several hours, the chances of saving the floor without mechanical intervention in its condition are zero. The wooden elements will absorb a lot of moisture and begin to swell. After collecting water, remove the baseboards and inspect the expansion joints on the walls. In a situation where the gaps between the walls and the floor begin to shrink, they should be widened with an electric saw, called a plunge saw. If the floor begins to swell to the point where there is no room on the board to expand further, the floor will come off the ground and go up.

You may not know the wood floor is water damaged until you see the surface damage. If the water system fails, the flow can seep into the wall and penetrate the subsequent layers of the floor. If water is localized to the wood floor for several hours or several days, the floor will become loose.

water damaged wood floors

The importance of flooring

Sometimes the detachment of the floor from the floor also depends on the quality of the underlayment of the floor . When the substrate is strong (e.g. has a compressive strength of 20-25 N/mm 2 and a tensile strength of at least 1 N/mm 2 with a flexural strength of 6 N/mm 2 ), a floor with short-term flooding may only warp and not detach from the substrate. The boards may become soft.

Flooded flooring

In case of continuous flooding of an apartment, water will get under the flooring made of laminate or laminated wooden panels laid with floating technology, i.e. not glued to the ground, but fixed. Water will get under the flooring through gaps between floor elements as well as through peripheral expansion joints between the flooring and the walls. In the first few hours, the effects of flooding will be visible in the form of swelling around the edges of the panels. Then the floor will unseal and the panels will rise. The cheaper the panels, the less resistant they are to water. High-density laminated panels, over 850 kg / m 3 with a hydrophobic coating on the side edges they will keep an undamaged surface longer. Floating installed flooring should be removed as soon as possible. If there is a waterproofing film underneath, it must be removed.

Parquet glued to the subfloor

A traditional floor made of wooden elements glued to the substrate is much more resistant to spills. In this case, the type of wood, its shrinkage factor and the thickness of the elements also play a big role. If a section of the floor has been flooded, but the elements are well held (they do not make a muffled noise when tapped), the floor can be saved. When the adhesive delaminates as a result of contact with water, it causes the boards to loosen. If a piece of the floor has risen but the planks have not come off, it can be left to dry. After some time, the floor may sink, and such a floor will still serve for several years. There is a muffled sound when walking, indicating damage.

The floor separates after flooding

Elements of the floor that are separated from the subfloor must be unconditionally removed. Elements are also removed in the adjacent area until the next board makes a proper sound during tapping, meaning it is permanently connected to the subfloor. The floor fragment must also be demolished to such an extent that the moisture content of the floor ensures that the boards will not warp. The humidity must be measured inside the floor screed using a hygrometric method. There are also times when there is no more water on the floor, but you know that the floor has absorbed a certain amount. At this point, the floor elements are still holding up, but after checking their moisture content, we can be sure that the amount of water absorbed will cause them to peel off. It’s best to do this immediately so that the subfloor can start drying as soon as possible.

Drying the floor

Floors are now built almost exclusively on floating foundations, meaning they are not permanently attached to the walls and floor. In this case, when flooding occurs, water gets under the floor and into the expansion gap between the wall and the primer, it filters onto the foil underneath, which covers the foam, passes under the foil, flows between the layers of foam, and spreads to the ceiling. In this version of the floor construction, the ceiling gets wet quickly. The subfloor must dry before a new floor can be installed. Water that has penetrated under the floor will stay there for weeks because evaporation is low. Natural drying of a floor screed can take up to several months. It is best to ventilate flooded areas in a draught. If necessary, you can speed up the process artificially by using condensation dryers or inside substrate drying systems. For example, you can create a network of drilled holes in the substrate so that you can introduce warm air through one of the holes and allow moisture to escape through the others.