When preparing to construct a two-story house, selecting the appropriate strip foundation is essential. In order to ensure stability and longevity, this foundational element is essential in distributing the weight of the structure evenly to the ground below.
There are various strip foundation types to take into account, each appropriate for various soil types and construction needs. The decision is influenced by various factors, including soil stability, load-bearing capacity, and local building codes.
Because of its strength and durability, a reinforced concrete strip foundation is frequently suggested for two-story homes. This kind of foundation entails digging concrete-filled trenches that are strengthened with steel bars to give the weight of the building above a sturdy base.
Alternatively, depending on the properties of the soil, a raft or mat foundation might be appropriate. Spreading the load over a larger area is an advantage of this type of foundation, especially in areas with high groundwater levels or poor soil quality.
| Factors to Consider | Recommended Type of Strip Foundation |
| Soil Type | A reinforced concrete strip foundation is suitable for clayey or expansive soils to prevent settling. |
| Load-Bearing Capacity | For heavy two-story houses, opt for a wider strip foundation with additional reinforcement. |
| Building Weight | A raft or slab-on-grade foundation may be preferred if the house is lightweight or built on stable soil. |
Factors for selecting tape type
One major cost component of building your own home is the economics of the process. The great majority of Russians construct their own one- to two-story homes. Pick a strip foundation type so that you can finish it quickly and without going over budget.
It will endure a long time and bear heavy loads if the technology is not violated and the parameters of the supporting structure—the tape—are accurately calculated. Additionally, you can set up a garage, basement, or technical floor for utilities within the foundation walls.
Three different dosage forms are currently in common use:
Which option to select will depend on the location of the house being built as well as the owner’s financial situation.
Made
Blocks, such as FBS 24-4-6 (base wall block length 2.4 m, width 0.4 m, height 0.6 m), are used to assemble the tape. Typically, a trench is excavated, much like under a single, massive foundation.
Instead of compacting the soil, a sand cushion 10 to 15 cm thick is poured. Sand may occasionally be swapped out for coarse gravel fragments, about 5 to 10 mm.
Blocks are distributed sequentially, end to end. Bending mounting loops with a sledgehammer is done. Cement mortar fills the interlayer gaps and joint spaces. Particular attention should be given to the brand of solution, which should be at least M100, if you are building a tape out of smaller blocks.
Benefits
- high construction speed;
- less preparatory work;
- construction can be carried out at any time of the year.
Drawbacks:
- some joints may separate after settlement, after which moisture and cold will penetrate;
- uneven distribution of load on different points of the foundation;
- low load-bearing capacity compared to monolithic tape.
- short service life.
On rocky soils, it is advised to construct a prefabricated foundation for a two-story home. They are less vulnerable to outside factors like frost and surface and ground water. Rocky soil doesn’t freeze or get wet.
Monolithic
A more intricate kind of foundation than one that is prefabricated. possesses high performance qualities and outstanding manufacturability.
But a lengthy list of preparations is needed before construction can begin.
For instance, formwork must be built, a cushion made of crushed stone and sand must be made, and reinforcement must be assembled to create a reinforced belt.
Benefits
- can be done independently, even by 1 person;
- does not require deep deepening;
- high load-bearing capacity;
- holds heat well;
- resistant to temperature changes.
Drawbacks:
- quite a labor-intensive process;
- long drying time for concrete;
- construction can only be done in the warm season;
- high cost of construction (in comparison with combined and prefabricated analogues).
On rocky, sandy, and clayey soils, a monolithic strip foundation is advised for a two-story home.
Combined
Here, strip bases are combined with monolithic and prefabricated types. For instance, mortar is used to create the basement walls and support cushions, while blocks are used to assemble the outline.
To level the ground beneath the walls, some people pour the upper monolithic belt. Reinforcement and formwork are also used in the process.
Benefits
- easy to build;
- relatively inexpensive;
- allows for adjustments.
Drawbacks:
- can be built in the warm season;
- requires assistance from third parties.
For a two-story home on rocky or sandy soils, a prefabricated foundation is advised.
Calculation of the dimensions and depth of the foundation
The first step in the technical specification for building a two-story house is studying the soil beneath the foundation. An evaluation is conducted on the state of the soil and the existence of subterranean aquifers. Therefore, since a two-story house is not a bathhouse, experts advise requesting a geodetic study. Here, a sober approach is necessary.
Soil types
Surveyors categorize soils into three groups:
- Heaving. These include fine sandy soil, silty sands, different types of sandy loam, loam, etc. Soil of this type tends to expand due to freezing. As a result, solid objects will be pushed out, causing their geometry to be disrupted.
- Non-heaving. This classification includes rocky and semi-rocky soils. They do not freeze, so they do not change their volume and do not squeeze out the contents.
- Slightly heaving. Coarse sand and gravel rocks. Changes in the volume of the earth are quite weak and practically do not harm the structure of the foundation.
It won’t be difficult to obtain a sample from geodesy experts and ascertain the soil’s composition. Avoid saving money on this.
Freezing depth
Different soils freeze at different times in the country’s northern, central, and southern regions. For instance, the standard freezing depth of soil in Moscow, under loam and clay conditions, is only 1.1 m, and in the Vologda region, it is already 1.43 m, according to SNiP.
It is necessary to bury the strip foundation 30 cm below the freezing line. These figures will be 20–40% higher in Karelia or Murmansk, where a two-story house’s total tape height can reach 2.5 meters.
Ground water level
Subterranean rivers and streams are among the crucial considerations made by builders.
It is impossible to construct capital buildings on heaving soils with high groundwater locations, especially on the strip foundation.
Some people assess the level independently by peering into the neighbors’ well. But it’s advised to order research research research before building a large house.
Wall material
The house’s box weighs several dozen or even hundreds of tons. It is incredibly heavy. The heaviest are the brick buildings. Frame and woodwork more easily.
In order to maintain such a large dwelling on its own, the strip foundation needs to be carefully calculated. It is advised to use pressure standards for various soil types for this.
For instance, the maximum load for a non-poudy is 35–60 t/m², and the maximum load for a heaving is 10–30 t/m².
Mass structure
At home, you ought to be working on a future project. The documentation lists the sizes and materials.
- Boxes,
- floors,
- roofs,
- Snow load.
This allows you to determine the type and dimensions of the foundation (prefabricated, monolithic, or combined), as well as the total weight of the house. Along the way, the depth of the tape must be determined while accounting for the area.
Example
We compute the mass of ceilings and walls that support loads. For instance, the box measures 6 by 9. Six meters in height. Material: 240 mm logs.
The weight of the house, accounting for loads (snow plus exploitation), is obtained using the online calculator program. 1850 kN = 185 t reserve. Weight of the house without coefficients and considering loads. reserve weight of 142 t. Weight of house box (materials only): 98 t. 142 t is the total load on the foundation.
The tape’s width should be 100 mm wider than the load-bearing walls, per the regulations. Thus, it will be 350 mm for us (standard 400 mm). Because the house is two stories, the builders advise increasing the foundation’s width by 100 mm and the tape’s height by 0.8 x 2 = 1.6 m. Plinth standard: 0.4 m. We also consider the depth and region of freezing at the same time.
The formula S> γn F / (γc R0) is used to calculate the minimum sole area, where:
- γn – safety factor for safety factor (constant value 1.2);
- R0 – soil resistance under the sole (for example, wet sand 2.5);
- F – maximum load of the house (185,000 kg);
- γc – coefficient depending on the soil and type of structure (for wooden houses 1.1).
All that’s left to do is enter each value into the following formula: S> 1.2 x 185,000 / 1.1 x 2.5 = 80,727 cm2. Divide by 10,000 mm, or 8 m², and round up to 80,000. Let’s double check: 30 x 0.5 = 15 m² is the total length of our foundation strip, and its width is 0.5 m. Our design house fits the future foundation 85% of the time.
We take into account the volume of solution V= h x b x l, where:
- V – volume of solution in m³;
- h – height (m);
- b – width (m);
- l – tape length (m).
Enter the values as follows: 1.6 x 0.5 x 30 = 24 m³. For a 9 x 6 tape, this is the amount of solution needed.
A two-story house’s strip foundation selection depends on a number of factors that guarantee stability and longevity. The best kind frequently depends on the particular soil conditions of your construction site. For instance, foundations built on clay soils must be made to withstand excessive movement brought on by the expansion and contraction of the soil.
It is advised to use a reinforced concrete strip foundation for clay soils. This kind lessens the possibility of differential settlement by distributing the house’s weight equally. It offers a strong foundation that can resist the stresses placed on it by larger constructions, such as two-story homes.
If properly reinforced, a conventional concrete strip foundation may be sufficient in regions with sandy or gravelly soils. This kind of foundation is reasonably priced for homes that do not experience significant soil movement and has a good load-bearing capacity.
It might be essential to install an engineered strip foundation with deeper footings in locations that are vulnerable to ground movement, such as those with expansive or highly compressible soils. With their minimal impact on soil movement, these foundations will protect your two-story home’s structural integrity over time.
The size and weight of your home must be taken into account when selecting the best strip foundation, in addition to the state of the soil. It is essential to seek advice from a licensed engineer or architect to make sure your foundation complies with local building codes and regulations and serves as a safe foundation for your construction project.
Choosing the appropriate strip foundation is essential for stability and longevity when designing a two-story home. This article examines several strip foundation designs that are appropriate for two-story homes, taking into account the local climate, building weight, and type of soil. Knowing the differences between insulated foundations for energy efficiency and more conventional reinforced concrete foundations can help homeowners make well-informed decisions that will guarantee their home is safe and sturdy for many years to come.
