Because of its longevity and low maintenance requirements, concrete flooring is a popular option for cellars and basements. The right way to pour a concrete floor is crucial, whether your goal is to add extra living space or a useful storage area. You will be guided through every stage of the procedure by this guide, which will guarantee a seamless and fruitful project.
A long-lasting concrete floor is largely dependent on preparation. You’ll need to gather the required supplies and equipment before you start, including plastic sheeting, reinforcing mesh, and a concrete mixer. To prevent any surprises during the pour, it’s also critical to measure the space and plan the layout. Long-term, careful planning will save you time and effort.
The real pouring process starts after everything is in place. To create a level surface, mix the concrete to the proper consistency, pour it evenly across the floor, and smooth it out. In order to guarantee that the concrete reaches its peak strength and longevity, we’ll also go over some crucial curing advice. You can achieve a professional-quality concrete floor in your cellar or basement by following these instructions.
Step | Description |
1. Preparation | Clear the area of any debris and make sure the surface is clean and dry. Fix any cracks or holes in the existing floor. |
2. Setting Up | Install forms or barriers around the edges where the concrete will be poured to contain it and ensure it stays in place. |
3. Mixing Concrete | Prepare the concrete mix according to the instructions on the bag. Ensure the mixture is smooth and lump-free. |
4. Pouring Concrete | Pour the mixed concrete into the prepared area, starting at one end and working your way to the other. Make sure to fill all corners and edges. |
5. Leveling | Use a screed or straight board to level the surface of the concrete. Smooth it out and remove any excess to ensure an even surface. |
6. Finishing | Finish the surface with a trowel to make it smooth. You can also add texture or patterns if desired. |
7. Curing | Allow the concrete to cure properly. Keep it moist and covered for at least a week to ensure it sets correctly and achieves its full strength. |
- Why do you need a concrete floor in a basement
- What to consider when installing a concrete floor in the basement
- How to choose a material for pouring the foundation
- How to prepare the basement floor for concreting
- How to waterproof concrete floors in the cellar
- How to make formwork and reinforcement of floors
- How concrete is laid
- How the surface is rubbed
- Drying
- Grinding and grouting
- Video on the topic
- Concrete floor in the basement. Part 1
- preparation for pouring the floor in the cellar
- Simple CONCRETE basement cover, with DOUBLE reinforcement mesh and further integration into the floor SCREED.
Why do you need a concrete floor in a basement
In most modern buildings, having a concrete floor in the basement is an optional feature. However, when we take into account how important this procedure is, there are some situations where pouring is simply unavoidable.
- If you plan to heat the basement for the purpose of arranging various utility rooms
- If you plan to use the basement as a living space
- When you plan to place a utility room, boiler room, sauna, garage, workshop, gym
- If you need a reliable cellar for storing food, wine
- With high soil moisture on which the building is being erected
- Ensuring a clean and beautiful appearance, comfort in the operation of the basement
Everything that will be in the earthen floored basement, including the furniture, pipes, equipment, and communications, is susceptible to deterioration. Even wall and ceiling finishes will deteriorate, and the house may even collapse in extremely rainy conditions and during extreme temperature swings.
What to consider when installing a concrete floor in the basement
There are some subtleties involved when pouring concrete for a basement floor. Though the overall plan of work is the same as for any other room involving the installation of a concrete floor, there are some nuances related to the basement’s location—deep under the earth—and the necessity of reducing the adverse effects of external factors.
- Depth of groundwater
- Taking into account the probable flooding of the structure and the slope of the site
- High-quality tamping of the soil under the floor is mandatory to reduce shrinkage
- Waiting a certain time after tamping to increase the strength of the coating
- After pouring, the concrete must be leveled to remove air bubbles in the thickness of the solution, so that voids in the floor do not appear in the future, destroying it and reducing its strength
- Basement waterproofing must be of high quality so as not to damage the screed and not cause the spread of dampness and microorganisms throughout the basement
If these subtleties are overlooked, the structure will be of insufficient quality and vulnerable, requiring repouring or repair. A quality, long-lasting concrete floor in a cellar or basement will be completed in about a week.
These kinds of structures are mostly filled with concrete by excavating a pit that is the necessary width based on the dimensions of the walls and formwork, filling it with a cushion of sand and gravel, installing formwork, adding a layer of waterproofing, reinforcing it, pouring concrete, properly maintaining it, taking down the formwork, and waiting for the concrete to solidify.
Concrete filling in a basement requires meticulous planning and execution. To create a sturdy and level basement floor, this article offers a clear, step-by-step tutorial on how to prepare the site, mix the concrete, and pour it. We cover every stage to guarantee a successful and seamless project, from preparing the site and erecting the formwork to actually pouring and applying the finishing touches. This guide will provide you with the fundamental knowledge required for a sturdy basement floor, regardless of whether you’re a do-it-yourself enthusiast or want to understand the procedure before hiring professionals.
How to choose a material for pouring the foundation
Prior to pouring the basement floor concrete, the best materials must be selected, and the working mixture’s composition must be calculated. The following materials are needed to prepare concrete mortar: water, plasticizers, grade M400 or M500 cement, crushed stone or expanded clay, sand. In the event that the other components don’t require any special considerations, it’s important to take the materials’ characteristics and operational conditions into account when deciding between crushed stone and expanded clay.
The following supplies are needed to pour the basement floor: concrete mortar, coloring agents, liquid glass, roofing felt for waterproofing, tar or mastic, steel reinforcement for strength, and a layer of thermal insulation (if you intend to install heated floors).
How to prepare the basement floor for concreting
The following preparation work is needed before pouring concrete on the ground:
- Preliminary cleaning of the surface from vegetation, debris
- Measuring the horizontal evenness of the base with a building level
- Removing a layer of soil 15-20 centimeters thick
- Thoroughly compact the soil surface, wait a certain time for shrinkage
- Making a crushed stone cushion, then a 50-100 cm thick sand cushion with watering and ramming (in the process, the sand cushion can lose about 25% of its height)
The following steps must be taken if concrete is being poured in a finished basement where the floor was previously coated: cleaning the old coating and removing any defects; removing chips and cracks by expanding and treating with a polymer composition or sand and cement; dismantling areas that cannot be repaired; using a milling machine to correct base height differences; and cleaning the floor of dust and debris (to improve the adhesion of the old coating to the new).
The following considerations should be made when determining whether or not a cellar or basement needs to have its floor concreted: the type of soil, the depth of groundwater, the likelihood of rain and melting snow flooding the structure, and the slope of the land. If the basement is completely dry and is higher than the groundwater level—that is, if flooding and increased humidity are not a possibility—then fill the space with crushed stone or cover it with plank flooring instead of pouring concrete.
But usually, a screed in the basement is still done – if not for the purpose of using the basement for various needs, then at least to give the structure greater strength and resistance to moisture. The question of whether it is possible to concrete the floor in the cellar does not arise at all – a concrete screed only improves the performance characteristics of the entire building and basement, there are simply no downsides. It is best to carry out the work in the warm season, when the ground is dry.
How to waterproof concrete floors in the cellar
The basement must be waterproofed in order to shield the floor from moisture and its damaging effects. Ultimately, concrete readily absorbs moisture while in use, so a well-applied layer of waterproofing will greatly increase the structure’s service life and prevent the need for floor replacements or repairs.
The procedure for setting up the basement floor’s waterproofing:
- Installing the roofing felt strips so that their end and side edges overlap the walls by at least 25 centimeters
- Filling with tar or gluing the joints of the roofing felt with mastic; for better fixation, you can glue them with tape or another similar material
- Excess parts of the roofing felt on the walls are carefully cut to the level and glued
The coating ought to be flawless, sealed, and free of any dents or damage. Any flaws are filled with mastic and secured with roofing felt fragments.
How to make formwork and reinforcement of floors
It is imperative that you reinforce the basement with reinforcement prior to pouring concrete, as this will strengthen the reinforced concrete structure and enable it to support heavy loads. The surface is first split into squares, and then 20–25 millimeter thick boards are used to mark the divisions.
The basement’s purposes and the floor’s operating circumstances are taken into consideration when choosing reinforcement. Generally, a road mesh with a rod diameter of 5 millimeters is used; however, you can also use metal rods with a diameter of 8–14 millimeters or choose a mesh composed of wire with a larger cross-section. When the solution is being prepared, steel reinforcing fiber is a good option to mix with it.
The number of layers used for reinforcement directly relates to the wall’s size. It is not advisable to place the lower portion of the frame directly on the waterproofing layer as this will expose the metal to corrosion. The supports that hold up the frame are roughly 50 millimeters high. At least 4-6 millimeters should separate the ends of the rods from the walls. The binding wire is used to secure the rods.
The formwork is installed regardless of the thickness of the basement’s concrete screed.
The floor area is divided into squares because it won’t be possible to fill the entire space at once if one person is working in the large basement. A worker can create 4-6 square meters of floor at a time in a satisfactory manner if he has access to a concrete mixer.
Initially, a damper tape is affixed to the basement walls to offset the slab’s thermal expansion. After pouring, the tape is glued so that it protrudes by roughly 10 millimeters above the floor. Boards are used to create formwork; detachable formwork is affixed to wooden or moisture-resistant plywood panels. The polystyrene plates that make up the non-removable one also serve as a layer of thermal insulation.
Special spacers should be installed during formwork installation; otherwise, the concrete may push through the boards and harden unevenly, forming a vertical wall that expands toward the bottom.
How concrete is laid
Before you pour concrete into the basement floor with your hands, beacons need to be installed. The installation of beacons, spaced one meter apart, will enable even filling of the concrete surface. A rail with a mark is placed on the elevations, or ready-made beacons can be used, and the top of the beacons is adjusted to match the bottom of the rail with the building level.
Concrete mortar containing M400 or M500 cement is used to create the floor screed in cellars and basements. To fill the first layer, a plasticizer or hardener is frequently added. Crushed stone or expanded clay work as fillers. For leveling, a vibrating beam or deep vibrator is employed.
The mixture of three parts sand, one part cement, five parts crushed stone, and one part water is used to prepare the solution. It is then poured into the formwork, leveled along the beacons, and either pierced with a steel rod or vibrated by hand. The basement floor is poured all at once.
How the surface is rubbed
A specific amount of time must pass for the concrete to harden after it has been laid, leveled, and any voids removed. The concrete should solidify to the point where a 4-millimeter-deep indentation only shows up when you place your foot on it.
- First, rough rubbing is applied to the wall and door opening areas, then to the remaining areas
- Rubbing is done with a hardener or topping for concrete, which must be sprinkled on the base and rubbed in exactly as much as necessary so that the mixture completely bonds with the concrete
- Then a second rough rubbing is done – after about half of the total mass of the topping has been used
- Another stage of rubbing is when the trace after stepping on the concrete surface is no more than one millimeter deep
Rubbing is applied as follows: 5 kg of topping per square meter should be used for small loads on the screed in the basement; 8 kg should be used for medium and heavy loads, as well as for coloring floors.
Drying
After a while, the screed gets stronger and dries. The initial setting requires a minimum of one day of waiting. Vacuuming is used to expedite the procedure while preserving the strength of the floor. An airtight mat is placed over the filter material on a level concrete floor, and a vacuum pump is attached to the center of the material to remove any excess moisture without destroying the screed layer.
When dried in this way, the concrete dries in a maximum of 7 hours.
You can step on the concrete to determine whether it has dried completely; the trace should be no deeper than four millimeters. The beacons from the set concrete can already be removed, and the grooves can be filled in with cement and sand, but walking is still only possible with a plywood plate in place. After that, a polyethylene film is applied to the floor, and it is left to mature for 28 days.
Grinding and grouting
Starting from the basement walls and doorways, grouting moves toward the center. It is done with a topping or concrete hardener. The grouting process is finished when all of the material has been absorbed by the surface. The last step is deemed finished if the depth of the trace left on the concrete is less than one millimeter. The entire process is repeated three times.
The loads operating on the concrete floor are taken into consideration when calculating the volumes of topping required for grouting. For example, large loads, such as those encountered in a gym, will require approximately 8 kg of grout per m2, while 5 kg will suffice for non-entered rooms.
Concrete filling for a cellar or basement floor is a project that can greatly improve the longevity and use of your area. By taking a methodical approach, you can make sure that the task is completed quickly and correctly.
The planning stage is very important. First, give the space a thorough cleaning, taking out any old flooring materials and debris. Installing a vapor barrier will stop moisture from penetrating through the concrete once the area is clear. This is particularly crucial in basements because moisture problems can arise there frequently.
After that, arrange your reinforcement and formwork. You can help your concrete floor take on the desired thickness and shape by placing the forms correctly. Concrete that has been reinforced with steel rebar or mesh will be stronger and more resilient over time, resisting wear and cracking.
The process’s most physically taxing step is pouring the concrete. Make sure the mixture has the proper consistency and is prepared correctly. After evenly pouring the concrete, level it with a screed. Organizing your work in manageable chunks will help you finish on time and with minimal stress. Use a float to level the surface and eliminate any air bubbles after pouring.
Give the concrete time to properly cure. There is no need to rush this important step. To avoid the surface drying out too quickly, which can cause cracks, keep it moist and covered if needed. It may take a few days to a week for this curing process, depending on the circumstances.
You can achieve a sturdy, level, and long-lasting concrete floor in your cellar or basement by carefully following these steps. This will increase the space’s usefulness and raise the value of your house. It will pay off in the long run to take the time to complete each step correctly, giving you a strong foundation for years to come.