Every investor knows that it is necessary to protect the walls of foundations and basements from moisture, groundwater and rainwater. Protection of the building structure from permanent destruction by water is the main element of waterproofing.
Water – although essential for life, it can be harmful to buildings and the people in them. Moisture ingress can occur due to floods and groundwater. Floods are caused by heavy and prolonged rains, sudden water runoff due to melting snow in spring or storms. Floods also cause blockages of ice and ice on rivers. Exposure to moisture due to lack of or damage to insulation results in well-known damage to paintwork, wall plasters and concrete.
In addition to the most famous and popular method – fixing the surface with asphalt concrete mastic or roofing felt – the underground parts of the building are increasingly insulated with modern materials(interior basement wall membranes): modified bituminous membranes, smooth and pressed film, synthetic rubber membranes, etc.
If a damp basement wall cannot be easily accessed from the outside do exterior basement waterproofing due to superstructures or adjacent buildings, internal basement waterproofing is the most effective way to meet these requirements. Thanks to optimally matched interior basement waterproofing detail product systems, even high-quality living spaces can be created in this way. Basements can be sealed from the inside without the need to dig foundations and earthworks. This type of waterproofing can be done even in case of leaks.
How the drainage system works
Drainage is a system made of special perforated plastic pipes surrounded by fine gravel. The bottom drain can be used in any soil and water conditions, even in the most difficult. Perforation allows water to be absorbed at the foundation. The slope with which the pipes are laid allows it to be diverted outside the building.
The gutter system is usually made of special plastic pipes. They surround the building from the outside, or – in the case of an internal sewer – pass under the house. They are surrounded by permeable material, usually fine gravel. The pipes have perforations that allow them to absorb water that has accumulated on the foundation. The slope with which they are laid makes it easier to drain water into the sedimentation tanks. From there it can be unloaded to several locations. Drain the collected water can be in the rain or combined sewer.
Another way is to drain the water into the ground 20-30 m from the building. This is possible when we have a large plot located on permeable land. The most common solution is to drain the water into so-called absorbent wells filled with permeable material such as gravel or other aggregate. Besides the typical pipe drainage, also known as interior french drain. It does not use pipes. Only the permeable bedding under the house allows the water to drain away. With the correct formation of the waterfall, the water has time to reach a permeable layer far from the building and drain into the ground.
In the case of interior perimeter drainage system, it is always necessary to carefully check the reasons for flooding the basement. Ground surveys should be carried out to determine the water level and its possible fluctuations. Also investigate the type of soil along with the filtration factor. Internal drainage, collecting water from under the building, creates a sinkhole. The difference in groundwater levels (a level higher than the basement level) causes water to flow under the foundation. If the soil is of low permeability, the pressure drop can be so large that the movement of groundwater towards the drainage pipes can cause the soil to wash out and under the foundation. Therefore, drainage should be carried out as high as possible above the level of the foundation and additionally covered with a sand and gravel filtering layer.
Interior basement walls
There are guidelines for basement walls that are in contact with the ground. Insulation is already provided with a layer of foam plastic 3-4 cm thick, but in practice thicker boards, 5-6 cm, which fit along the entire height of the underground part of the basement wall. Insulation can be dispensed with if blocks with good thermal insulation are used for use or the wall is built in the form of multi-layer walls.
For wall insulation, it is best to use waterproof polystyrene foam or extruded polystyrene foam boards. These materials do not require additional protection from moisture and contact with the ground. Basement walls can also be insulated from the inside. This will be especially beneficial if there are rooms in the basement that require heating. Warming them from the inside will quickly heat up to the desired temperature. For thermal insulation, polystyrene foam plates are used, which are glued to the base. Framing interior basement walls of the basement is made in the form of plaster on a reinforcing mesh or from drywall, lining or panels.
From the outside and from the inside, the foundation wall is equally exposed to groundwater and moisture. This determines the implementation of the waterproofing on both sides.