Nowadays, in the private construction, purchased concrete billets used as lintels are practically not used. Today, most suburban housing owners prefer to make door and window lintels with their own hands.
For self-manufacture of filler concrete from filler concrete, it is not at all necessary for you to possess special skills. All that is required of you is to take due care of the materials of this article and follow all the instructions given in it.
Materials and tools
For the successful implementation of the task you will need the following supplies:
- a set of edged boards of suitable thickness;
- a set of metal corners;
- thin reinforcing mesh;
- polyethylene film;
- nails with a wide cap;
- self-tapping screws of the right size;
- knitting wire.
As for the tool, then for work you will need to prepare:
- ordinary hammer;
- electric jigsaw (hacksaw);
- electric drill or screwdriver;
- assembly tool (mount);
- Trowel (trowel);
- bucket small capacity.
Preparing the box
Arrangement of the lintel begins with the manufacture of wooden frame (box), used to fill the concrete mix and obtain a building element of a given shape. To install such a box, you will need one lower and two lateral wooden shields, from which you can later assemble the formwork.
The linear dimensions of the finished panels should correspond to the dimensions of the window opening, and the side panels should cover it both in height and in width. The lower shield is made exactly according to the size of the opening being closed. In the sides of the formwork, pre-prepared holes for the knitting wire, by means of which the shields will be held in a given position. The bottom and side surfaces of the boards are then laid with a plastic film, which is attached to the formwork with glass nails.
- Assembling the box usually starts with the installation of the lower shield, which, both in width and length, is carefully adjusted to the dimensions of the window opening. The correctness of its installation is controlled horizontally with the help of a building level, after which several props are installed under this shield (taking into account the preservation of the position set at the level).
- The side shields are set in a specific sequence; at the same time one of them is first fixed on the wall (with the help of screws, for example) and only then it is fixed on the already mounted lower shield. Note that for walls lined with silicate or gas silicate blocks, this task is considerably simplified, since the shields can be fixed on their surface using ordinary nails.
- The second side shield is also fixed first on the wall, and then mounted on the bottom of the box with screws. When fixing the formwork, you should not save on self-tapping screws, because when you dismantle the structure, you will be able to unscrew all the fasteners and use it for other purposes.
- In order to avoid the “collapse” of shields under the pressure of a concrete mortar, the side walls of the structure are fastened together with a binding wire. Such wire (pre-cut into pieces) is pulled by a double ring into the previously prepared holes in the shields. After that, a reinforcing bar suitable for the size is inserted in the center of the twist, with which it is tightened.
- Then the finished reinforcing mesh is laid in the formwork. It is placed in such a way that the bars of the reinforcement do not touch the walls of the box; at the same time small stones are placed under its lower row.
For pouring improvised jumpers, it is best to use concrete mixed with small gravel.
Jumper filling and formwork disassembly
Concrete casting operations are recommended to be performed together; while the assistant will be able to serve you with a bucket of concrete, which is usually prepared at ground level or floor. Concrete should be poured very carefully, making sure that the composition is evenly distributed throughout the volume of the box and penetrated into all its cavities. In addition, when arranging the window jumpers with their own hands (in the process of leveling the concrete mix), it is necessary to ensure that the fill level coincides with the upper cut of the brickwork.
The dismantling of the formwork usually begins with the cutting of the knitting wire, after which it will be possible to proceed to unscrewing the self-tapping screws fastening the shields together. Then by mounting the side shields are separated from the finished lintel, after which the support is removed and the lower shield is removed.
The surface of the resulting lintel often does not look quite perfect and, of course, needs additional processing. To do this, first remove the remnants of the wire, and then in order to remove all irregularities, plaster its surface.
In practice, see the following video on pouring reinforced concrete lintels: