Workshop on laying parquet on a plywood base

Much has already been said about the advantages and quality characteristics of a parquet board, we will tell you how to lay it correctly. In this process, we will have to solve the following tasks:

1. Protection of parquet boards from moisture from concrete – choice of materials and technologies.
2. Correct determination of the orientation of the drawing in a room with a curly perimeter.
3. Optimizing workflow – saving time.

In urban construction, the floor will always be concrete, with the exception of the few historic buildings that have retained a solid wood base. The concrete floor allows the use of any technology and takes significant loads. We will take advantage of its strength and ability to hold the anchor.

Plywood is an ideal base for parquet boards. Smooth and even, it has no “contraindications” for use with any kind of wood flooring and, with sufficient thickness (15-22 mm), it may well replace the leveling screed. Strictly speaking, parquet board is also some kind of plywood, processed in a special way. It will be attached to concrete with a plastic dowel with a self-tapping screw for wood.

Question.Why not use a quick-fit dowel (BM)?

Answer.Firstly, the self-tapping screw attracts the planes better, the BM in such cases often jumps out. Secondly, with a screwdriver, you can smoothly control the force in order to avoid constricting and pulling out the dowel. Third, the heads of the fasteners must be recessed. To “hide” BM, you need to deepen each cap with a punch, and this is an additional operation.

So, the order of work is supposed to be as follows:

1. Cutting square plywood sheets.
2. Cleaning, dust removal.
3. Application of a protective preservative layer.
4. Laying plywood.
5. Laying parquet boards.

We need the following tools:

1. Carpentry power tools – hand circular, jigsaw, impact drill, screwdriver.
2. Compressor with pneumatic stapler (staple gun).
3. Vacuum cleaner (preferably industrial).
4. Carpentry hand tools – level, square, cord, hammers, mallets, etc..
5. Auxiliary – extension cords, spatulas, “combs”, rags.

Plywood sheets with dimensions 1525×1525 mm and 15 mm thick were chosen as the base material. To get even squares, we will cut them into 4 equal parts.

Question.Why cut whole sheets? Why not put them entirely as they are, because this will not change the square?

Answer.Sheets of considerable area (1.75 m² and more) with increasing humidity, they can noticeably expand in linear dimensions. This can lead to mobility of the finishing layer and loosening of the anchor (dowel). The smaller the elements, the lower the coefficient of linear expansion and the more reliable the fit..

Since the area of ​​the room is large and there are a lot of sheets, for their prompt sawing, we recommend making a rigid conductor, similar to the one shown in the photo.

It can be used to quickly cut sheets into four pieces. To do this, set the stop to 0.76 m plus the distance from the edge of the plate to the edge of the teeth of the circular saw blade (about 40 mm).

Next, it is necessary to drill holes in advance to minimize dust and debris during installation. For this we need a template. We mark out one sheet – we apply a 3×3 grid of equal cells with an indent from the edge of 30 mm. Making holes at the intersection of the axes.

Further, for marking, you will only need to apply the template to the bottom sheet, and mark the holes with a drill. Then the template is removed and the holes are drilled completely. With a certain skill, you can drill 3-4 sheets at a time. This approach saves time for marking and drilling each sheet separately..

After all the preparatory work, we select the necessary tools and materials, remove the rest from the room and do a thorough cleaning, cleaning and dusting the concrete base (screed).

After cleaning, only a stack of plywood should remain on the floor surface.

Even 15–20 years ago, there was no other way to prepare sheets of recycled wood (fiberboard, chipboard, plywood) for use, other than to cover them with drying oil on both sides. Thus, the sheets were “canned” and became hydrophobic. Technological progress and international trade relations have provided craftsmen with a wide alternative to this expensive and inconvenient method. It manifested itself in the form of preservative primers, but not for covering sheets, but for concrete. In our case, it is a one-component polyurethane primer-primer PRIMER / PU of the French company ACM.

Gently apply the composition with a roller to the base. If necessary (if pale “islands” appear), apply a second layer.

Plywood layout. The sheets will be attached to the dowel through a layer of glue. It is needed for additional grip and a snug fit of surfaces (plywood and concrete). In our case, we chose Artelit RB 110 glue, which will also be used for parquet boards..

Attention! There should be a gap of 5-10 mm between the edges of the sheets.

In order to speed up the work process and save time on cutting plywood, you should choose the right base line. It should be as long as possible. Then it is easier and faster to move further from it, it serves as a persistent beacon. When crossing the OL, priority is given to the one that claims the longer length (it will be longer if it is not interrupted).

The main line (OL) is an even (along the cord) border of the row, into which the factory (or evenly cut) edges of individual elements (boards, sheets) are lined up during laying or installation. It is detected when the first row is arranged and serves as a guideline for the further arrangement of one layer. In this case, elements, the smooth face of which is OL, can be trimmed along other faces.

After laying the first row and determining the OL, lay the second and subsequent rows on glue and dowels.

Attention! Any sheet material is laid on a plane with a gap of seams.

The last sheets of the row in our case come to beveled edges. Each sheet of these rows is trimmed individually.

The final view of the plywood base, on which the main lines (OL) are clearly visible:

Key moment. Determine the main line of the parquet board. This is a demanding job that must be done by a master with great skill. The OL of the board must:

• be as long as possible – to simplify the installation of the lighthouse row and all subsequent rows;
• take into account the presence and location of niches, openings, ledges. For the “starting point” OL is taken the straight line of the greatest length, passing tangentially without cutting through the greatest (more than 1) number of obstacles (conventionally it is called the “line of obstacles” – LP);
• be at a distance of one width of the element (board) from the LP.

Similar difficulties arise in rooms with a complex perimeter, intersecting corridors, bends, etc. In apartment-type rooms, everything is much simpler, but the rules remain the same.

Having determined the LP and attaching a board to it, we pull the cord along the outer edge. It will be OL.

We put the first (“lighthouse”) row according to OL on glue.

Attention! The first row should be laid as carefully as possible. The slightest misalignment of the lighthouse row can result in significant discrepancies of the groove-ridge connections in the middle or in the last rows.

To align the transverse joints, we adjust the second continuous row along the raw glue

We fix both rows with staples.

Attention! The staple serves as a temporary clamp for the adhesive to set. Drive the staples into the bottom edge of the board groove.

The lighthouse row, ready for further installation, looks like this:

From it in the direction of the room we lay out the remaining rows, fixing them also with staples.

Attention! When pressing the board, use a wooden extension (a piece of parquet board) to avoid breaking the comb..

The staples are driven into the bottom edge of the groove. Gently so as not to fill his space.

At corners and beveled mates, each board is trimmed individually.

In places where the flooring adheres to the wall, use wedges for a thorough pressure.

The floors in the rooms located behind partitions on the path of the OL are laid according to the lighthouse row.

The last stage – the installation of the plinth – is carried out after the glue has completely dried according to the instructions given.

Calculation of the cost of 1 m² plywood-backed parquet flooring:

The assortment of parquet boards, glue and primers is large, in our work we used high-quality material of an average price category. The price spread can be up to 50% of the data presented in the table.