The irregularities of a parquet floor can be made up by applying a thin layer of mortar. This operation, called "patching", is relatively fast and very simple to perform with pre-dosed products.
Old floors with irregularities can not receive a new coating directly. Flatness defects do not allow the installation of tiling or even parquet and laminate that would be unstable and could come loose or dislodge (especially in case of clipped installation). The asperities of the support would not fail, eventually, to show through a flexible coating such as carpet, vinyl, linos.
To avoid these problems, the easiest way is to apply a patch that guarantees a smooth and regular laying support. This thin solid layer makes its flatness to the support and makes disappear the crevices (in particular the spaces between the blades, being an old parquet).
Different types of patching
There are many different names of patching in the trade depending on the type and the importance of surface irregularities to be removed.
- "Liquid" leveling compounds are used to erase defects less than 2 cm deep.
- The thicker leveling mortars are suitable for flatness defects of 2 to 4 cm deep.
- Beyond 4 cm, we enter the field of smoothing screeds, made with a conventional cement mortar. Peelings up to 4 cm have the distinction of being self-leveling during their implementation. Simply apply them with a flatbed so that they spread spontaneously and smooth without the use of a trowel, as required by cement mortars.
A preparation phase to treat
A patch is not a cache-misère. This is a way of preparing the floor for a new floor. Despite their qualities, the patches do not provide a minimum of preparation. The support must be clean, dust-free, sufficiently strong and rigid, without trace of moisture. It is necessary to get rid of any projecting element such as tip, screw, splinter, etc.
In addition, a hooking primer applied to the wool roller allows the patch to better adhere to the support. If the original floor is very cracked and if significant differences in thickness are to be filled, we can resort to a fibered patching. In all cases, provision should be made for drying time of about 3 hours.
- On an old wooden floor, brush the slats to dust them off.
- If it has been waxed, scour the entire surface.
- Otherwise, treat the oily areas with a cloth soaked in a trichlorethylene substitute.
- If the floor has not been waxed, wash it with a scrub brush and an ordinary floor detergent.
- This facilitates the adhesion of a bonding primer followed by patching mortar.
- With a large painter's knife (spatula), remove stuck soils.
- Scrape them until you reach the wood.
- Examine the condition of the fasteners of the slats of the floor.
- Tear the nails protruding and replace them.
- Do not leave loose blades: the patch does not mask the important defects and does not consolidate a faulty construction.
- It is imperative to refit the blades that move.
- Reclave them in full or screw them back in the joists or joists.
- Use a screwdriver and countersunk screws.
- Using a sander, level the protruding blades to provide proper flatness before applying a primer and then patching mortar.
- Recap and grout the slots with wood pulp to prevent mortar from leaking between the blades.
- Spread it with a coating knife.
- Mix the smoothing mortar in a bucket and mix it with a mixer mounted on a drill.
- Pour it on the floor.
- Spread it with a trowel by applying it at one time.
Tips from handymen
- The patching taking place at one time, this involves preparing a quantity of mortar sufficient to cover the entire surface to be treated.
- It is imperative to strictly adhere to the drying time recommended by the manufacturer, depending on the type of flooring to be laid on the floor. Otherwise, there is a lack of adhesion, especially in the case of tiles.