How to dig a strip foundation with an excavator, what are the nuances, comparison with digging by hand

Any construction project needs to have a strong foundation built, and one of the most popular types is the strip foundation. This kind of foundation supports the walls of a building by extending continuously around its exterior. The technique you use to dig a strip foundation will have a big impact on how efficient and expensive the project is.

Digging a strip foundation with an excavator can save you a great deal of time and effort when compared to digging by hand. Because they are strong machines that can move a lot of dirt quickly, excavators are great for bigger projects or when dealing with difficult soil conditions. To guarantee the task is completed correctly and safely, there are crucial considerations to make when utilizing this equipment, though.

However, for smaller projects, hand excavation of a strip foundation may be more accurate and economical. More control over the trench’s width and depth is made possible by this, which is essential for the structural stability of the foundation. Despite these benefits, manual digging is time-consuming and labor-intensive, frequently requiring a team of workers to finish the task effectively.

The benefits and drawbacks of excavating manually vs using an excavator for a strip foundation will be discussed in this article. To assist you in selecting the approach that will work best for your construction requirements, we will go over the important variables to take into account, including project size, soil type, and budget.

Trench shape and depth

Underneath the house’s load-bearing and enclosing walls is the strip foundation. The width of the trench on each side must be at least 15 cm greater than the intended tape. This is required in order to leave room for the formwork.

The more space that needs to be left for formwork, the more intricate and substantial it is. However, since the trench’s walls will support the formwork, you don’t want to dig it too wide.

The width of the trench that an excavator digs will match the width of the bucket. It won’t be feasible to compute every detail to the nearest centimeter in this situation. Ordering specialized equipment with appropriate parameters and following the guidelines for trench size calculation are essential.

The tape’s height is used to compute depth. The height of the cushion made of sand and crushed stone that will be poured beneath the tape’s base must be considered in the computations. You must excavate a trench that is as deep as the tape plus the cushion’s height.

Using an excavator to dig a strip foundation has many benefits over manual digging, including speed and efficiency gains. However, there are some special considerations that must be made, like making sure all measurements are accurate and handling obstructions. For smaller projects, manual digging may be more accurate and economical, but for larger foundations, an excavator works best because it saves labor and time. Making the right decision for your construction needs is made easier when you are aware of the benefits and drawbacks of each method.

Marking scheme

One of the necessary first steps is to mark the location where the pit will be dug. Mark the pit’s perimeter with a rope and some pegs.

Draw a line around the exterior walls’ internal perimeter first. Install pegs at the inner corners and extend a rope between them to accomplish this. The angles need to be verified to be 90 degrees.

The length of the marked walls and the diagonal distance are checked to be sure after applying the internal markings. Everything needs to line up with the project blueprints. Following that, a rope is used to mark the line that indicates the distance to the pit’s outer boundary.

Partition marking is done following trench excavation beneath the surrounding walls. Here, you should concentrate on trenches that have already been prepared. This phase is equally crucial, and it is also the time to verify that the angles are accurate.

To mark the base, the following instruments are required:

• rope (or strong cord);
• construction level (laser or bubble);
• clothespin nails or clamps for securing rope to stakes;
• wooden slats;
• construction square;
• wooden pegs (or reinforcing bars);
• tape measure with single tape.

Performance of work using equipment and price

You should determine exactly how much digging you are capable of before you begin. The truth is that without a foundation, a trench that has been dug cannot be left empty. Furthermore, until the following season, the completed foundation cannot be left without a box at home.

This implies that you must start digging when it is certain that all other construction phases will be finished on schedule and that sufficient funds and labor will be available.

Typically, fall is when foundation preparation takes place, once the ground has thawed and warmed. In this instance, the walls and roof of the house must be completed before the first frost. The entire construction season is still available.

If you have enough time before winter to finish the remaining tasks, you can dig a trench in the summer. Although digging in frozen soil is also an option, the cost will be higher, and further work might need to be done to repair the hole’s walls and bottom once it thaws.

The excavator will create a trench with smooth walls, but you might need to manually trim the hole’s bottom after it’s finished. Either way, it will take less time and effort than manual digging.

Different cities have slightly different average costs for construction companies to dig trenches with an excavator:

How to dig manually?

First, the following preliminary tasks are completed:

• clearing the entire building area of ​​debris and tree roots;
• removing turf along the inner perimeter of the tape;
• moving the top fertile layer of soil to the garden part of the site;
• allocation of space for dumping of excavated soil.

After that, they begin to dig. At least 1.5 meters are separated from the trench by the soil. The depth needs to be continuously monitored and adjusted to match the height of the tape while accounting for the site’s slope.

Filling the trench with water is necessary to compact the bottom. Everything ought to go smoothly. In order to prevent disturbing the bottom’s geometry while work is being done in the trench’s already-dug portion, sand can be sprinkled on and compacted once more.

It will be essential to construct a drainage system at the lowest point of the construction site. Now is the time to widen the trench to allow for the installation of a drainage pipe.

When performing work on loose soils, a trapezoidal trench should be dug, ensuring that the width increases from the base to the top.

Time costs

The following variables affect how long it takes to finish all of the work:

• tape length,
• required depth and width,
• soil quality,
• number of working people.

This is not a quick process, anyway. Simultaneously, the rate at which the excavation is completed is crucial because the soil has a tendency to collapse and the hole beneath the house’s foundation needs perfect walls and a level bottom.

Possible problems

The weather’s unpredictable nature is one of the key issues. It’s highly likely that it will rain while digging is being done over a few days or weeks. It will saturate the pit’s bottom and lessen the soil’s ability to support weight.

The soil collapse within the trench is another issue. If the excavation takes longer than expected, the walls will need to be adjusted before the formwork is installed, which will take more time and work.

Cost and terms of excavator services

You can bring builders to the location, and they will dig a trench by hand for a fee. The price per cubic meter for their services is about 800 rubles.

When compared to hiring and using a small excavator, this is orders of magnitude more expensive. However, there are times when manual labor must be used because it is not possible to transport construction equipment to the construction site.

A group of construction workers can excavate a site more quickly than an individual developer could. but far more slowly than what an excavator can accomplish.

When is it better to choose what and why?

It is preferable to prepare the pit yourself when building a small object. If not, the construction estimate is going to be excessively high.

Special tools are needed for homes with extended strip foundations. In this instance, the excavator’s rent and the labor costs of the specialist operating it are savings rather than needless expenditures.

It is preferable to invite workers if the site’s characteristics make using equipment impossible. When constructing on a small lot or close to another building, this might be your only option.

When compared to digging a strip foundation by hand, using an excavator can save a significant amount of time and physical strain. The heavy lifting is handled by the machine, which expedites and improves the process. However, in order to prevent harming the location or the nearby structures, careful planning and expert execution are needed.

However, digging by hand allows for more control and precision, particularly in confined areas where an excavator might not fit. It also does away with the requirement for large machinery and the related expenses. For small projects or locations with limited access, hand digging may be more practical despite being labor-intensive and time-consuming.

The scale and complexity of the project, along with your budget and schedule, should all be taken into account when deciding between an excavator and manual labor. Large-scale foundations and projects with a strict timeline are best suited for an excavator; smaller, more meticulous jobs are better served by hand digging.

In the end, each approach has benefits and drawbacks. Knowing the subtle differences between them will enable you to choose the option that best meets the requirements of your project. A successful strip foundation depends on careful planning and execution, regardless of whether you choose to use the speed of an excavator or the accuracy of hand excavation.

Video on the topic

Digging a trench for a strip foundation. Mini-excavator

Digging a strip foundation with a mini-excavator ● RE-FLOODING

Digging a strip foundation with an excavator