How to make a monolithic strip foundation with your own hands: pros and cons, technology

Building a monolithic strip foundation may be on your list of things to do if you’re taking on a do-it-yourself construction project. Because of its strength and stability, this type of foundation is a popular choice for many builders and homeowners. Building a sturdy foundation can make all the difference, whether you’re planning to build a little hut or a larger structure. This post will go over the specifics of creating a monolithic strip foundation yourself, including advantages and possible disadvantages.

The longevity of a monolithic strip foundation is one of its main benefits. Compared to other techniques, this kind of foundation is exceptionally strong because concrete is poured in a single, continuous layer. It also offers a strong foundation on which to support the weight of your building. We’ll walk you through the exact steps involved in pouring this kind of foundation, enabling you to make sure your project is built on a solid and dependable foundation.

Even though this kind of foundation has advantages, there are drawbacks as well. It can be a labor-intensive process that needs to be carefully planned and carried out. Errors can occur at several stages, from excavation to concrete pouring, which could result in problems later on. We’ll go over these elements and offer advice on how to steer clear of typical pitfalls so that your do-it-yourself project runs smoothly.

By the time you finish reading this article, you’ll know exactly what benefits and difficulties come with building your own monolithic strip foundation. Regardless of your level of experience, you’ll be more capable of completing this project and laying a strong basis for your building. So let’s get going and begin the procedure!

Pros	Cons
Sturdy and durable, good for various soil types.	Labor-intensive, requires significant physical effort.
Even load distribution, which minimizes settling.	Cost of materials and tools can be high.
Provides a solid base for buildings, reducing the risk of foundation issues.	Requires careful planning and precise execution to avoid mistakes.
Can be done by DIY enthusiasts with the right tools and skills.	Time-consuming process with a long curing period before construction can continue.

Building a monolithic strip foundation on your own can be a rewarding DIY project, offering benefits like cost savings and a solid base for your structure. However, it"s important to weigh both the pros and cons before diving in. The technology involves pouring concrete continuously to form a single, strong strip that supports the entire load of your building, which requires careful planning and execution. While the process can save money and give you hands-on satisfaction, it also demands precision, a good understanding of construction techniques, and considerable physical effort. This article will guide you through the steps involved, highlight potential challenges, and help you decide if this project is right for you.

Scope and types of strip monolithic foundation

The kind of soil and its characteristics, the number of floors, the degree of groundwater passage, the freezing point of the ground, and other variables all play a role in the selection of a particular kind of foundation for a future structure. The primary parameter—the amount of load that the supporting structures place on the support and foundation—is impacted by each of these indicators.

• Large weight of the walls of the house made of stone, brick, concrete
• The presence of heavy floors in the structure – metal, reinforced concrete
• The presence of heterogeneous soils on the site for the construction of the facility (which, in turn, provokes uneven distribution of loads on the foundation)
• Bookmarking a basement, garage, cellar in a future home

A horizontal, level strip with a constant cross-sectional area and shape is called a monolithic strip foundation. The strip extends beneath the interior walls and around the whole outside of the structure. Reinforced concrete is used to create monolithic structures; the mixture is poured into formwork that has an assembled reinforcement frame inside of it.

• Monolithic – concrete is poured into the formwork with reinforcement directly on site.
• Prefabricated – made up of blocks manufactured at the factory, 25% less durable compared to the monolithic version.

It is possible to build a monolithic strip foundation on any kind of soil. In dry sands, sandy loams, and loams, the structure is engineered above freezing point. Soils that are medium to highly heaving need to be buried 20 to 30 centimeters below the freezing line without any drainage. The foundation can be lowered above the freezing line if they choose to perform drainage and swap out heaving soil for non-heaving soil.

Drainage measures are implemented first if the site has a high groundwater level because hydrostatic pressure will cause the foundation to distort. In this instance, setting up the foundation can also be done using pile technology.

Pros and cons

Certain features, benefits, and drawbacks are involved in the construction of a strip monolithic foundation. So, you must thoroughly research the crucial details before you begin developing a project and plan, doing calculations, and carrying everything out.

• Universality – the structure is suitable for a house made of any material, with any number of floors
• Simplicity of construction – the technology of erecting a monolithic strip foundation consists of digging a pit, installing formwork, laying reinforcement and pouring concrete
• High level of strength – the most important advantage of the structure, allowing it to easily withstand serious load-bearing loads
• Long service life – on average, such a reinforced concrete foundation can last up to 150 years
• Relatively small volume of earthworks, concrete works
• No need to involve special equipment (may be required later for laying floor slabs, columns and other construction works)
• Minimum requirements for soil, groundwater level
• Simple installation scheme – all calculations with drawings are quite possible to do independently
• Low cost of the structure – so, if you compare a monolithic foundation and a project made of reinforced concrete slabs, the first option will cost 45-55% cheaper (in the general estimate, the cost of the foundation is about 10% of the total amount)
• Possibility to create a full-fledged basement, garage, cellar

The high material consumption, significant labor costs, long-term concrete mortar hardening, inability to complete the project on uneven terrain, and required thermal and waterproofing are just a few of the drawbacks.

Calculation of strip foundation

Any monolithic strip foundation is designed with consideration for the standards and specifications found in GOST R 52086-2003 and SNiP 3.03.01-87, whether it is for a single-story building or a multistory structure.

The results of hydrogeological surveys conducted on the property and the operational history of nearby buildings must be taken into consideration in the computations. Making a drawing for the future foundation is the first step in determining the properties and composition of the soil at the anticipated depth.

Depth of foundation

This parameter is directly influenced by the building’s weight and the depth at which the local soil freezes. To have the best bearing capacity, a large ground-level cottage needs to have the following indicators: the minimum of 50–70 centimeters, or the depth at which soil freezes plus 10 centimeters. The depth is greater when the basement is present. The freezing boundary has no effect on the depth of deepening if a shallow base is formed.

Regarding the groundwater border, the foundation passage’s depth is determined by where the layer is expected to be relied upon; it can be made either below or above the line. If this is the case, drainage and corrosion-resistant tape treatment are unquestionably necessary.

Width and height of a monolithic tape

The size of a monolithic strip foundation can be any. Everything is dependent on the kind of building.

• Buildings from gas/foam blocks, silicate and other light piece materials – the width of the load -bearing walls is taken + 10 centimeters
• Frame houses -wall width (for a 2 -story building) or -10 centimeters from wall width (one floor)
• Brusth house- the width of the beam +/- 10 centimeters (the size depends on the number of floors)

Regardless of the material, the general formula for determining the height of a strip foundation is: snow level in the construction region + 20 centimeters (but not more than 2 width values). The length of the house is calculated as the total of its load-bearing walls. You can determine the area of the foundation sole given all the parameters.

Calculation of bearing capacity

The monolithic (reinforced) strip’s foundation should be able to support all weights placed upon it. In order to evaluate the stability of the underlying soil when it influences the loaded base, a calculation is done. computed using the following formula:

Folding the weight of all building materials used in construction along with any temporary loads yields the total load. For this, you can use specialized calculators or tables (which are freely accessible over the network) that show the resistance to calculation based on the type of soil and the operating conditions.

Installation technology

There are guidelines that must be followed when performing collective monolithic strip foundation. Prior to beginning work, each step must be thoroughly studied.

Site marking

The soil at the location is thoroughly inspected before designing. Subsequently, they create markers, attempting to adhere to the current location as closely as possible. This is because the subsurface structure may be heterogeneous, and even a small shift in the structure can have negative effects. For example, there may be a cavity or subsidence rocks suddenly beneath a portion of the foundation.

The masters recommend against making significant changes to the suggested location. It is still crucial to follow the project even if positioning cannot be done with a centimeter accuracy.

Use wooden formwork and a cord for marking. Using lime mortar to draw lines is also acceptable. Make a foundation diagram first, then move it to the location. Almost all work cannot be done without a drawing.

The marking process is as follows: mark the corner first, then draw a side from this point that is ideally parallel to the fence or road, and finally, using the Egyptian triangle method, make a right angle. To prevent the rope from sagging during the excavation process, cast-off stakes should be placed close to the structure’s exterior walls.

Check the diagonals next; they should line up with a maximum deviation of two centimeters. You can divide the project into manageable chunks if the house has a complicated floor plan. Separate foundations are marked for heavy equipment, with at least a 10-centimeter expansion joint between them and the main tape. This area is carefully filled with non-flammable bulk material after filling.

Digging a trench for deepening the monolithic tape and installing backfill

Building a strip-monolithic foundation for a house requires consideration of the building’s overall scale. The amount of excavation required and the specialized equipment needed are directly correlated with the project’s size, building dimensions, and basement situation. In the event that there isn’t a cellar or basement, the dirt is removed in accordance with the markings, leaving a space of roughly 50 by 80 centimeters on each side for the installation of the formwork structure.

All of the dirt will need to be removed if the home has a basement. The pit’s measurements ought to be two to three meters greater than the foundation’s. extra space set aside for formwork spacers. Specialized equipment is used to remove large volumes of soil; this equipment is typically rented. It won’t be less expensive to hire a group of "diggers," but it will take much longer.

The top layer of soil, which is fertile, is spread out throughout the garden after being laid separately. The remaining dirt is just piled up and part of it will be removed and some will be used as backfill.

The soil is compacted and leveled after the bulk of it has been removed. Unevenness (areas 25–30 centimeters deeper than the established depth) is frequently visible if an excavator was used; all of this is carefully filled in and thoroughly tamped.

The trench or pit must also be completely leveled and tamped. For these uses, a vibrating plate is preferable. Since the entire structure will be pressing against the ground, even slight voids and unevenness could eventually cause the strip foundation to shrink and crack.

Generally speaking, experts recommend adding a layer of fine to medium-sized sand to the bottom, moistening it, and compacting it using a vibrating plate. It will be sufficient to fill two layers, each measuring 15 to 20 centimeters. Water is added to each layer individually, then it is compacted.

Certain projects call for backfill made of gravel and sand. In this instance, the sand is covered with a layer of crushed stone that ranges in size from 30 to 60 millimeters and can be as thick as 15 centimeters. The layer is then compacted. It is best to compact and lay out layers every five centimeters. By doing this, you can increase the density of the soil and increase its carrying capacity.

Installation of formwork

Install the formwork prior to pouring the monolithic strip foundation. Typically, the structure is composed of strong, moisture-resistant materials that can tolerate concrete pressure.

Creation and installation of a reinforcing frame

It is necessary to reinforce the monolithic strip foundation. It is possible to strengthen the structure’s resistance to loads and deformation forces by connecting metal rods into frames.

• Working reinforcement – longitudinal rods that take on bending loads.
• Clamps – made in the format of horizontal transverse rods that connect the frame.
• Vertical clamps – connect rods that are in different planes.

• Outbuildings, light buildings – 8-10 millimeters
• Buildings made of timber, piece materials – 10-14 millimeters
• Heavy houses made of blocks, bricks – 14-18 millimeters
• The largest diameter of reinforcement in low-rise construction is 22 millimeters

A240 or class A3 rods are used to reinforce every component and unit of the monolithic strip foundation structure. Six working rods are provided by the reinforcement cage. The standards state that transverse reinforcement should be carried out in steps of 30 to 60 centimeters. Wire with a cross-section of 0.6–1 millimeters is used to tie the cage. If there is a unique hook or gun, that is good.

Practically never used, this kind of connection is only permitted on the structure’s straight longitudinal sections.

• L-shaped clamps – are applied with an overlap, where the outer rods are connected to the inner ones
• Rigid overlap connection ("paw") – the ends of the rods are bent at an angle of 90 degrees, then connected with wire
• U-shaped clamps – additional rods of the corresponding shape are installed with an overlap, providing an additional frame for horizontal/vertical rods
• Reinforcement of obtuse angles – the rod is bent at the top, joined with an overlap at the bottom, then an additional clamp is assembled at the bend point

• The length of the tape is multiplied by 4 – the length of the longitudinal rods
• The length of the tape is divided by the step between the vertical rods, multiplied by 4 – the length of the vertical rods
• The sum of both values ​​​​above – the total length of the rods for the frame
• The length of the rod is 6 meters – dividing the value by 6, you can get the number of rods
• Add about 7-10% to the resulting value

The pre-tied reinforcement frame is inserted into the formwork so that the metal rods are fully recessed into the thickness of the concrete mixture after pouring, keeping them from touching either the trench’s bottom or the formwork’s walls.

Pouring the foundation tape

Concrete with a strength class of B17.5/B20 is used to pour monolithic strip reinforced concrete foundations; B25 is an option.

• Pouring is carried out in layers – the thickness of one layer is up to 20 centimeters
• All layers are alternately compacted with a special vibration tool without touching the reinforcement cage
• While the poured layer has not set, the next one is poured over it

Vibration allows air and voids in the concrete to escape, distributing the mixture uniformly inside the formwork and improving the monolithic strip’s strength indicators.

Use of gutters is preferable when pouring from specialized transport because it facilitates delivery and prevents the solution from falling from a height (materials can delaminate when falling from a height of 150 centimeters or more).

The maintenance required for concrete varies depending on the weather. To stop moisture from evaporating quickly, the strip needs to be covered with polyethylene film when pouring in dry, warm weather. Because of the concrete’s deep depth, wetting won’t do much here, so it’s crucial to properly cover it.

The concrete will lose up to 50% of its strength after three days at a temperature of roughly +20C, and the formwork can be removed after five days. You must wait for up to 14 days at +10C; at +5C, the setting process halts, and you must either rewarm the concrete or insulate the formwork.

Backfilling cannot begin until the completed strip foundation has been waterproofed and insulated, which takes 28 days from the time of pouring.

If you’re willing to put in some effort and pay close attention to detail, building a monolithic strip foundation yourself can be a satisfying project. Because of its strength and longevity, this kind of foundation is a good option for a variety of building styles. You don’t need to hire a contractor to get a professional-looking result if you follow the instructions carefully and monitor the process closely.

One of the main advantages of a monolithic strip foundation is its robustness. It provides a continuous, reinforced base that can handle a lot of weight, which is particularly useful in areas with unstable soil. However, it"s essential to weigh these benefits against some of the challenges, like the amount of manual labor required and the need for precise measurements and mixing. Mistakes in this stage can lead to bigger issues later on, so patience and accuracy are crucial.

Even though there are multiple steps in the process—from formwork and excavation to pouring and curing—it will be worthwhile to take the time to comprehend each one and adhere to best practices. A strong foundation for your construction will be ensured by the up-front work you put into properly planning and carrying out your foundation. To avoid future issues, remember the significance of reinforcement and curing periods.

In general, building a robust foundation for your project at home with a DIY monolithic strip foundation can be an affordable option. You can accomplish the task and feel proud that you built it yourself if you prepare carefully and are dedicated to using the right methods. But keep in mind that every construction project is unique, so don’t be afraid to ask for help or refer to other sources when necessary.

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