Maintenance of foundations consists in monitoring their condition, in the prevention and timely elimination of the causes that cause their destruction. Such reasons include substandard laying of the foundation during construction, non-liquidated areas of the base with weak soil, lack of ventilation in the underground, lack of proper drainage of water from the walls of the building and the presence of faulty water supply and sewerage networks.
Routine repairs include replacement of dropped stones, repair of cracks,
restoration of damaged plaster, repair of slopes, repair and restoration of drainpipes.
After thorough cleaning of the embedment site, the fallen stones are replaced, cracks and seams are closed on a cement mortar of 1: 3 or 1: 5 composition.
The blind area is restored and repaired, dismantling the damaged area with the capture of the adjacent area by 10-15 cm. The cover of the blind area is made with a proper slope from the wall.
The plaster is repaired by beating off the lagging part of it, cleaning and rinsing this place, on which a new plaster is then applied.
Overhaul of the foundation consists in replacing the old one, broadening the sole, joining cracks with cement mortar.
To replace the pillars, the building is hung out by jacking it up. If the building is wooden, then immediately hang out the entire wall and install supports. After hanging the building, the plinth and the fence between the posts or chairs are dismantled and then the well is torn off to lay a new post.
Its depth depends on the properties of the soil. With heaving soils, the sole is laid below the level of soil freezing. In cases of filling the well with sand (sand does not change its volume when frozen), the depth of the laying is 1 m. In non-learning soils, the foundation is laid to a depth of 0.7 m. In addition to rubble stone, well-fired bricks can be used. When laying the pillars, the edge of the foundation is not brought to the lower crown by 5-6 cm. A cement mortar screed is placed along the edge. A layer of roofing waterproofing is laid on the screed. Lower crown antiseptic. A board wrapped in tar paper is tightly laid in the gap between the masonry and the crown. After that, the pick-ups are arranged in the order described above, and the base is restored. Strip foundations they are shifted in sections with a length of 1-2 m. The building is upset (jacks are removed) when the new masonry is sufficiently strong.
Work on changing foundations begins with the installation of fasteners - supports. After that, separate sections of the foundation are torn off and a horizontal line is pierced to lay the unloading steel beam. In the upper part of the walls, where the supports are installed, through holes are punched for the steel beams. One end of the beam rests on a support, and the other on racks installed inside the building; thus, the wall is suspended from these beams.
The damaged foundation is dismantled in separate sections 1.5-2 m long, leaving the punches in the old foundation. After disassembling and clearing the site, the new masonry is carried out on a cement mortar, with a dense eyeliner in the rows under the old masonry and the stones of the upper row under the laid unloading beams, observing the dressing of the seams.
When overhauling foundations, special attention should be paid to the condition of the waterproofing. Its restoration is the most demanding and difficult job. Foundations are usually replaced from the layers below the waterproofing in order to preserve it.
Particularly responsible work when waterproofing basement walls. In these cases, the surface of the wall is cleaned of dirt, old mortar and plastered with cement mortar.
To better isolate the walls of the basement from groundwater, a 25 cm wide trench is dug from the outside of the building, which is filled with mint clay.
Alexey Shamborsky, 08/10/2015
The basement of the building is exposed to aggressive effects of many factors. It is in need of repair more often than other areas. It is impossible to delay with it. Indeed, the destruction of the basement reduces the durability of the entire structure.
So that damage to the plaster does not lead to the growth of mold and does not allow moisture to destroy the wall, it is necessary to correct the situation and timely repair the basement of the building. As a rule, it consists in the restoration of seams, new plastering of hotel areas. Sometimes when repairing a plinth brick house individual bricks have to be changed.
Step-by-step instruction
First, release the lower part of the wall from contact with the ground. To do this, use a shovel.
Then remove all fragments of plaster that do not hold well, you must try not to miss voids, they can be identified by tapping. All loose plaster is beaten off with a hammer or chisel.
Then they clean the surface from dirt and dust. Use a wire brush to thoroughly remove any remaining plaster. How to do this work, you can look at the photo or video.
All surfaces that need to be protected from plaster, for example, window frames, must be pasted over with masking tape. It will protect important areas from contamination.
Defects found in the masonry are moistened before the repair of the brick plinth lining. This is necessary to ensure better contact of the plaster mixture with the surface.
To fill the existing voids, bricks of the appropriate size should be selected. You can cut fragments of the desired size from aerated concrete blocks.
The next stage of repairing the basement with your own hands is to fill the voids with prepared bricks and fix them with masonry mortar.
Before plastering the surface, it must be thoroughly moistened. To do this, you can take a bucket and a brush, but it is easier and faster to wet the wall with water from a hose.
Then a solution (waterproofing sludge) is prepared for waterproofing. The mixture is diluted with clean water.
The solution is applied to the restored areas in 2 passes. First, a thin layer of 1 - 2 mm, when the first layer begins to set, a second layer of 3 mm is applied. In this case, you can use a brush or a wide spatula.
The applied layers must stand for a day. You can continue to work the next day.
Then the plaster solution is prepared.
A 2-layer application is carried out again. First, a layer of 10 mm is applied. The plaster is rubbed with force over the surface, moving the trowel in a semicircle.
In order for the walls to be smooth in the end, it is advisable to use plaster strips, during the installation of which a level should be applied. Such strips have several varieties. In this case, they are made of wood.
The next layer of plaster is applied with a thickness of 15 - 20 mm.
The plaster is carefully applied over the entire surface, it is advisable to fill the entire surface with it up to the foundation. Then it will be possible to talk about a complete and high-quality repair of plaster basement.
The base point for removing excess mortar will be not only the plaster strips, but also the undamaged layer of the cladding, as in the photo.
When the surface is dry, it is leveled with a plaster float.
When one day you noticed some destruction on the foundation, you urgently need to start carrying out work to repair and strengthen it.
To do this, you should define necessary materials, the sequence of works and their scope.
For the owner of a brick house, repairing the basement sets the following tasks:
- how to make it more durable bearing capacity foundation;
- how to prevent then various deformations of the soil next to it.
Why does the basement collapse?
First of all, take control of the cracks that have appeared not only in the basement, but also in the foundation of the structure. Install several markers across them, for example, on the inside of the base - beacons made of alabaster or gypsum, on the outside - from DSP (cement-sand mixture).
Watch them for about 20 days. If the markers are intact, just repair the cracks. In the same case, when they collapsed, it is necessary to understand the reasons for their appearance.
Only then can you take measures that concern renovation works to stop future destruction. You can do the work yourself or invite builders with the necessary equipment.
If you notice that there are distortions in the door and window openings on the house or soil deformation has appeared around the perimeter, you need to pay attention to this, since these processes indicate a dangerous state of the base.
When the foundation is hidden from visual inspection, and it is difficult to determine the reasons for the increase in cracks, it is necessary to drill control pits. They will help you understand the condition of the basement of a brick house and find out the causes of deformation.
They can be divided into "man-made", which appeared due to human actions, or natural.
Also, deformations and cracks can occur due to:
- the wrong choice of place for construction, for example, did not take into account the levels of groundwater;
- poor design - they forgot about drainage, did not put blind areas, did not protect the base from moisture;
- problems that arose during the laying, for example, associated with low-quality building materials;
- trees planted close to the house with a powerful root system;
- unaccounted for vibration power internal and external influences during the operation of the house;
- artificial waterlogging of the soil along the perimeter of the building.
Tip: use for building a house only building brick, never use hollow bricks or silicate bricks for the foundation.
It is recommended to use solid ceramic for this.
Materials
The purpose of the basement repair is to install a fence outside the underfloor space. It must be strong and stable enough to withstand groundwater atmospheric precipitation. Therefore, it is so necessary to choose the right building materials.
Natural:
- sandstone;
- shell rock;
- limestone;
- basalt;
- granite;
- silicate or red brick.
You can also use prefab or monolithic concrete, as well as cement-based mortars with:
- sand;
- sand and lime;
- sand and clay.
For the manufacture of concrete mortar prepare cement, gravel or crushed stone, sand and water (1: 3: 5: 1). Their number depends on the amount of work.
There is also a direct dependence of the base / plinth thickness on the material:
- brick - 120 mm;
- rubble stone - 200 mm;
- reinforced concrete - 100-120 mm.
Strengthening the foundation
The instructions for repairing a basement are reminiscent of the creation of an external reinforcing foundation.
- Start work from the control hole when you need to dig a trench along the perimeter of the old foundation to its bottom.
Tip: to improve the quality and safety of the process, open the old base and bring the new one in small sections, about 1.5 m each in increments of up to 4 m, while insuring the walls with wooden struts.
- Connect it to the base / plinth fittings by welding or tying wire. Frame cell - 200x200x200 mm.
- Install formwork in the trench, for example, laminated plywood.
- Fill the frame with concrete.
Advice: if you do not have time to do the work at the same time along the entire perimeter of the foundation, do it in parts, i.e. while the concrete hardens in one area, collect the reinforcing cage in another.
Screw piles for repair
The price of such work will be significant, therefore they are very rarely used for old foundations.
If there are sufficient material resources, then screw piles can be safely used instead of pneumatic equipment, since this will compact the soil, and not loosen it.
- Dig a trench along the perimeter of the old basement and install piles in its bottom to the required depth.
- Fill them with concrete and tie them together with an I-beam.
- Fasten the structure to the old plinth with metal anchors and fill with concrete.
- Protect the reinforcing foundation with waterproofing.
Tip: drain if there is a threat of seasonal flooding of the base.
With waterlogged soil.
Usually from the inside of the basement, widen the ventilation holes in the basement.
Output
Repair of the basement of an apartment building or a private one is necessary for many reasons, the main of which is to protect the structure from complete destruction. Various methods and materials are used for this. In the video presented in this article, you will find additional information on this topic.
