Construction on marshy soil requires a special approach and the use of special technologies. The soil contains particles that form quicksand. They are unstable, so in the cold season such soil is subject to heaving. In summer, the soil is greatly washed away, which should be taken into account not only when designing, but also during the construction of the house. The question of which foundation is better in marshy terrain is also acute.
How to build a house on a swamp
Construction of a building on marshy terrain requires planning and the use of modern technologies to ensure the reliability and durability of the structure. The work is carried out in several stages:
- Geological research – the survey will determine the characteristics of the soil and the level of groundwater, as well as identify seasonal fluctuations. Based on the data obtained, the design is carried out.
- The choice of foundation – what kind of foundation can be made on marshy soil depends on preliminary research.
- Site preparation – installation of a drainage system and soil strengthening .
- Construction of the foundation of the selected structure.
- Construction of walls and roof – lightweight materials are used, such as aerated concrete or frame structures. This will reduce the load on the foundation and ensure the stability of the building.
- Installation of engineering systems – water supply, sewerage, heating and ventilation.
- Completion – exterior finishing and landscaping. It is also important to protect the house from moisture, so it is worth installing a drainage system.
Construction problems
The construction of a foundation and a house on marshy soil is associated with a number of difficulties and problems that must be eliminated to ensure the reliability and durability of the structure.
The main ones are:
- High groundwater level – on peat bogs and other similar soils, flooding of the foundation and basement is possible. This fact will require the installation of an effective drainage system to remove excess moisture.
- Low bearing capacity of marshy soil – to solve this problem, it is necessary to use special types of foundations. Geological surveys will help determine which foundation is best for marshy terrain.
- Soil mobility – seasonal fluctuations can lead to deformation and destruction of the foundation. Therefore, the foundation on marshy terrain must be carefully selected, and the land must be strengthened.
- Corrosion of metal and rotting of wood materials due to high humidity – structures will require additional protection.
- Difficulties with the installation of engineering systems – due to the high level of groundwater in the marshy area, the installation of communications is difficult. It is often necessary to use autonomous water supply and sewerage systems.
There are also environmental restrictions. When choosing which foundation is best for a swamp and when constructing it, it is necessary to consider possible impacts on the ecosystem. It is also advisable to comply with environmental protection legislation.
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How to determine the type of soil
To choose the right foundation to make on marshy soil, you should determine the type of soil. It can be determined in several ways:
- Visual inspection – pay attention to the color, structure and moisture level. A dark shade may indicate the presence of organic matter in the bog peat. The structure can be loose, viscous or dense. High humidity indicates the presence of groundwater near the surface.
- Laboratory studies include granulometric analysis, study of organic substances, determination of their volume, density and moisture content.
- Drilling wells and taking samples for subsequent analysis.
- Geodesy – includes seismic exploration, electrical exploration and ground penetrating radar.
The surveys should be carried out by specialized experts. Only on the basis of professional research can one really correctly determine what kind of foundation can be built on marshy soil.
Types of foundations on a swamp for a house
There are several options for arranging a foundation for marshy soil.
Slab foundation
A monolithic slab foundation on marshy soil is one of the best options. It resists pressure and can shift together with the structure if the ground starts to move. It is not difficult to understand how to pour a foundation on a swamp. Concrete mortar is most often used. It is better not to use factory slabs. This will save on materials and rental of construction equipment.
A slab foundation on marshy land is erected in several stages:
- Digging a pit of suitable size.
- Filling the bottom with crushed stone.
- Creating a sand layer.
- Filling the sand with water and compacting it.
- Installation of drainage to remove moisture.
- Installation of formwork.
- Preparation and pouring of the solution.
- Covering the frozen fountain with stones to strengthen it and improve its aesthetics.
To protect the foundation and extend its service life, it is worth doing thermal and waterproofing.
Pile foundation
A pile foundation on a swamp is built quickly. Screw piles on swampy terrain can be installed at different depths. This allows you to make a level foundation on a relief surface. The maximum depth of pile installation is 20 m, the number of elements depends on the area of the object. They are located along the perimeter of the site or at a distance of 1.5 m. From above, the foundation components are connected using steel or wooden profiles.
Advantages of the foundation:
- high strength;
- service life of more than 100 years;
- possibility of construction in winter;
- speed of construction;
- low costs.
There is no need to insulate or protect against water, since the foundation is located above the surface. However, corrosion protection will be required due to the humidity on the site.
Strip foundation
A strip foundation is not often built on a swamp. This solution is possible if several conditions are met:
- the area must have good drainage;
- the highest place for installing the foundation is selected;
- There should be no springs or other underwater sources near the future house.
The strip foundation is constructed as follows:
- Digging several holes (9 to 12) will serve as a support for the future structure and will allow the weight to be distributed evenly. The depth of the wells should be below the level of groundwater flow.
- Installation of reinforced concrete pillars into holes.
- Creation and compaction of soil embankment around structures.
- Formation of a cushion over the embankment in the form of a reinforced concrete platform for proper load distribution.
Once completed, the main structure can be erected. A strip foundation is ideal for building a bathhouse on a swamp.
Reinforced concrete piles
On such a foundation, it is possible to build houses of 1 or 2 floors from different materials. It consists of reinforced concrete pillars that are buried in the ground and a connecting strapping. The piles are driven into the soil using special installations. One pillar is installed quickly. The entire foundation is erected in 2-3 days. Due to the support in solid ground, the base is reliable and durable. The foundation resists loads due to seasonal soil movements.
Features of installing a foundation for a house on marshy soil
The first thing to worry about is finding a suitable place to store materials. To do this, you need to arrange pile decks. They will also be needed for the movement of workers. When selecting materials, you need to pay attention to corrosion resistance. If it is steel, you need to consider the brand and thickness of the rolled metal. Before installing the product, you need to paint it.
If a pile foundation is being installed, it should be remembered that the solid layers in swamps are located deep. The pillars are driven in to the dense layers. It is important to install the required number of piles so that the structure can withstand the weight of the building.
When constructing a strip foundation, the soil should be strengthened and drained. This is done by adding weight. The area is marked out and divided into zones of 1.5-2 meters. Then, wells are drilled in a checkerboard pattern. Drainage pipes are installed in them. Upon completion, the area is covered with geotextile and covered with sand. Such a system will gradually squeeze moisture out of the soil. After the soil is compacted, the foundation can be installed.
How to conduct communications
Communications are arranged after geological surveys based on the design solution. The document reflects the types of engineering systems, laying routes and depth. The main stage of water supply arrangement begins with site preparation and drainage. Next, trenches are dug, in which pipes are laid. A waterproofing layer is applied on top. Upon completion, each circuit is connected and tested. If everything is in order, the channels are buried.
Electricity definitely needs to be carried out through the air, given the soil’s oversaturation with moisture. To create a sewer system, it is recommended to use a sealed septic tank, which requires periodic pumping.
Vegetable garden in marshy area
When creating a vegetable garden, you need to follow the following rules:
- Installation of drainage if it was not done during the construction of the house.
- Addition of soil improvers – sand, loam and humus to create a loose fertile layer.
- Deoxidizing the garden – use slaked lime, wood ash or dolomite flour.
- Selection of suitable crops – vegetables should be moisture-loving and resistant to temperature fluctuations. You can grow beets, potatoes, cabbage, carrots, etc.
- Planting vegetables in raised beds so that the roots do not suffer from excess moisture.
- Regular fertilization of the soil, since peat is not the most fertile soil.
- Avoiding heavy flooding of the garden with water, even if there is visible drying out. Moisture is retained in the deep layers.
- Mulching beds to protect against erosion and sudden temperature drops.
Thus, we have analyzed the features of building a house on a swamp and what kind of foundation is used for this. We found out how the foundation is erected, how communications are laid and how a vegetable garden is made on the site. Each event is complex and requires a professional approach. Therefore, it is better to entrust the choice of a suitable foundation for building a house on a swamp, as well as other work, to specialists.
