How to properly knit reinforcement for a foundation - proven ways

When pouring a band and slab foundation one of the most important stages is knitting reinforcement. It is necessary to take into account a lot of points - from choosing a wire of a suitable diameter to the nuances of using the tool. However, this work is quite possible even for non-professional builders. Advantages of knitting In individual construction, two methods of joining rods of reinforcement are common: knitting and welding. Moreover, the first has a number of advantages:

• The design remains elastic - the chance of its damage in the case of microvibration of the basement, caused by temperature changes or ground motions, is minimal, unlike a rigid welded frame.
• At the welding location, the rod becomes more brittle, may be corroded over time. It is at the joint points that cracks and faults subsequently appear.
• Do not need an expensive welding machine or the involvement of professional welders.
• Welding is much more expensive, because you need to spend not only on welding equipment and qualified specialists, but also on electricity.

Selection of materials and tools

• Depending on the design of the house, its weight, the depth of the foundation, its width, and the type of reinforcement soil, a steel rod( or a modern composite) with a diameter of 8-10 mm is needed.
• For its connection you will need a steel knitting wire. Its diameter is 0.8-1.2 mm( GOST 3282-74), it is selected depending on the diameter of the reinforcing bar. Calculate the required number is quite simple - one node needs 25-30 cm of wire. Buying it, believe how flexible and elastic it is. The most convenient way to knit a wire is with a special hook. Pay attention to the handle was rubberized and comfortably lay in his hand. In the absence of a hook, pliers can be used.
• Strong rubberized gloves allow better control of the grip and avoid scratches.

Process subtleties

When knitting reinforcement for a slab foundation, only 2 rods intersect in one node, and all the rods lie in one plane. On the prepared base parallel to each other rods with a distance of 25-30 cm are laid. Above, perpendicular to them, the second row with the same pitch is stacked. The intersections of the reinforcement are fixed with a wire joint.

In the case of a strip foundation, the structure will already be three-dimensional - the bars are not only horizontally but also vertically. The horizontal levels, which are connected by vertical segments, can be 2-3 or more. In this case, the distance between the rods in the horizontal level should not exceed 20 cm.

1. The knitting wire is cut into pieces of 25-30 cm in length. It is better to practice in advance on several lengths to determine the most convenient length.
2. All pieces are bent in half, the folding position is not clamped. Work with these blanks faster and more convenient.
3. The wire billet is located below the intersection of reinforcing bars, diagonally to them. It folds up again so that the wire wraps around the joint, and the loop and free ends are at the top and close to each other.
4. A hook is inserted in the "ear" from the bottom up. Then they grasp the free ends and rotate clockwise twist both parts of the workpiece together.
5. The workpiece is twisted in 2-4 turns. If you overdo it, the wire can burst.

After fixing all the nodes, they are inspected once again, they are convinced of the strength of the structure. Now you can start pouring concrete.

New technologies to help builders

Manufacturers of professional tools produce special pistols for binding reinforcement. Such a device is able to replace the work of several workers, and the connections made by them are of a different quality. The main disadvantage is a high price, the basic models cost from 35 thousand rubles.

If there is no extra money in the building budget, and there is nowhere to rent this tool, then a usual screwdriver will come to the rescue. In the socket of the screwdriver, instead of the bit, a bent long thick nail or a small piece of thinner reinforcement is inserted, the device is switched to small revolutions. The part replacing the hook is introduced in the manner described above, and the contraction occurs due to the torque of the screwdriver. The use of mechanized devices is particularly justified if a smooth reinforcement is used, which is much harder to bind by hand.

When laying the armature and its binding, it must be remembered that from this stage depends the strength of the foundation and all knowledge for many years. It will be impossible to remodel and fix the work after casting the concrete.