Construction of a base for an extension to the house

Many homeowners often face the problem of building an extension to the house. It becomes necessary if you want to expand your living space, supplementing it with additional rooms. The construction of a basement for an extension to the house has its own characteristics, unlike the technology in new construction. Here it is required to find a way to dock it with the old base, so that it is reliable.

What are the ways to bind the foundations of

Today, there are two main ways to interface the foundations. The first method is based on a rigid connection technology using steel reinforcement. Apply it in the event that the foundation has long been settled, and further draft does not threaten him. In this case, it is necessary to calculate the new foundation, which should show that it does not hang on a new foundation and will not cause additional draft of the house above the permissible values. It is permissible to consider reliable rigid jointing of foundations only when the soils on the site are not rampant. Otherwise, it is not advisable to pair with such a technology.

The device of such connection is made using the following technology:

• First set the type of the base under the house itself, it is tape or columnar. Important parameters are such as depth and linear dimensions. The depth is measured after digging a hole near the wall to the very base of the basement. To measure the width, you need a metal rod or wire, at which the end is bent at 90 degrees. Punch or, if necessary, hammer it under the foundation so that the hook was horizontal relative to the plane of the surface of the base. Then turn it upright, and pull it up against the back of the foundation. After that, you need to make a notch on the rod according to the level of the outer wall. Then we extract the rod, performing in reverse order all previous actions. The distance from the edge of the rod to the mark left by you is the width of the foundation
• It should be noted that the soils of the soils affect the various types of foundations in different ways. For this reason, if a tape type was built under the house, then it should be done under the extension. It does not matter that the walls of the foam blocks are light enough. A new foundation is laid to a greater depth than the old one was laid.
• In the mating points in an old monolith, drill holes of diameter slightly larger than the diameter of the reinforcement. There is a rule, according to which the depth of these holes should be equal to 35 diameters of the used reinforcement. Outside, there should be twice as much of the rod as it will fit inside the old basement. This is the working length.
• If the base is not very large and is not large enough to meet these conditions, then the holes are drilled to the middle of the foundation. In this case, the hammered rods should look like anchors. To do this, they are cut along and inserted into the resulting gap proppant. This method will reliably fix the reinforcement inside the concrete monolith.
• After that, calculate the required number of reinforcing bars. A closed contour of the new foundation assumes the use of 5 rods on 0.25 m2 of the base wall. The bars are cut by a Bulgarian or an emery machine in an amount that depends on the width of the future base. Now the prepared rods must be driven into pre-drilled holes and welded to their ends with small washers.
• After that, you can safely fill the foundation in the prepared formwork. At the same time, the fitting, which is located outside, will be tightly sealed in the body of the new base.

Let's consider in more detail the second way of connecting two foundations. It is based on the use of a deformation seam between them.

It is much easier and cheaper to make a mating of foundations in this way. In this case, the sequence of works is as follows:

• In a necessary place a separate foundation is being erected, which is in close proximity to the old one. It may not be as powerful as the main one, but it must also be carefully calculated so that it is strong and reliable. The distance between the two foundations should be about 5 centimeters. This can be achieved if we put in the junctions the usual boards of the required thickness, which are wrapped with a roofing paper or with a polyethylene film. It is not necessary to clean them after construction.
• If the soils are too flat, then the floor in the extension should be slightly below the floor in the house, just by the amount of the supposed deformation. When constructing buildings with a number of storeys not exceeding 2 levels, a distance of 2 cm can be observed between the walls.
• The gap between the bases and the walls is filled with any insulation. Previously, for these purposes, mainly used the patella, but today there is a huge amount of modern materials, among which the most popular are mineral wool and expanded polystyrene. After foaming and warming the joints are sealed with weatherproof elastic sealants, and the connection point itself is covered with decorative patches that are attached to one of the walls. Most often, the wall of the capital building is chosen for this purpose.

How can I build a foundation for the

extension If you chose the first method for use, the base will have to be made the same as under the main house. This involves the technology of creating foundations using this method of pairing two bases. When choosing the 2nd method there are no restrictions on the type of foundations, the main thing is that they are convenient and economical. Completely suitable tape, columnar, as well as a foundation on screw piles.

When self-laying the foundation, it is necessary to make some work before the construction of the foundation itself begins. It is advisable in the beginning to consult with a specialist who will give you advice on choosing the optimal type, and will also provide calculations of its reliability. After this, you need to make the layout of the plot and mark out the contour of the future structure on it. To do this, drive the pegs in the corners and pull the cord between them. It is necessary to calculate the diagonal of the site by the formula: c = √( a² + b²), where, a and b are sides, and c is its diagonal. The rope is measured along the length equal to the first diagonal and checked for compliance with the size of the second diagonal. If necessary, make an adjustment. Similarly, marking the inner perimeter of the foundation after retreat to the required width in depth. A complex foundation is marked by the method of dividing into rectangles, which are calculated separately. After the marking, excavation work is carried out.

The most important thing in the construction of an additional extension to the house is the choice of the construction of the foundation and a competent interface with the old one. If we consider the economic side of the issue, then the hard interface will be much more expensive than the joint by means of a deformation seam. One way or another, the process of constructing a foundation is very responsible, and its complexity increases with the age of the building.