To prevent water damage to your foundation, you must create a blind area around your home. If the land where your home is situated is sloping, this becomes even more important. Water may collect on the slope and flow toward the foundation, which over time could cause major structural problems. We’ll walk you through every step of building a dependable blind area that efficiently directs water away from your house in this article.
Making a strong plan is essential from the outset. You will need to take into account the particular features of your slope, the kind of soil, and the average amount of rainfall in your area. Knowing these variables will help you choose the right supplies and techniques for your project. The foundation for a successful and long-lasting blind area will be laid during this planning stage.
Now that you have a plan in place, it’s time to gather your supplies and equipment. Sand, concrete, gravel, and waterproofing membranes are examples of common materials. Basic tools like a shovel, wheelbarrow, and level are also required. Everything will go more smoothly and effectively if you have everything ready before you begin.
From clearing the site to installing the materials and making sure the drainage is adequate, we will guide you through every stage of the building process. Even if you’re not experienced with DIY projects, you’ll find it manageable because each step will be clearly explained. Our mission is to work with you to design a blind area that will protect your house and make it look better overall.
Why is it important to properly create a structure on uneven terrain??
Occasionally, when developing in flat terrain, builders overlook the need to provide a shield around the foundation of the structure. This is deemed incorrect, but if the house is situated on an incline or if the surrounding terrain is uneven, with varying elevations of the ground, then the lack of this structural component will be disastrous. A classic of Russian reality is a house perched atop a small hillock on a plot.
The soil is washed away by rain and melting snow that rolls down the slope, causing the building’s foundation to "go" down and become unstable or partially exposed. This is prevented by creating a dependable blind area right next to the plinth wall.
For the protective coating to be completely effective, the construction technology must be strictly followed when creating it for a sloped foundation.
What does a high-quality design give:
- Sediment is discharged to a safe distance. This is especially important in uneven areas, where there are holes near the foundation, sudden changes in ground height. Water will flow along the slope of the blind area from the base of the building into the storm sewer and drainage system. The foundation building materials will remain intact, the landscape will not change under the influence of atmospheric phenomena, the building will stand much longer, without cracks and chips at the base.
- Thermal insulation. The protective layer isolates the lower layers of soil from air penetration. Thanks to this, with the onset of frost, the moisture in the soil does not freeze, the earth does not swell and does not create pressure on the foundation of the house. For objects on a slope, this is also relevant because, being on a hill, the building is blown by winds stronger than on a flat area. The blind area helps to keep the heat on the first floor, in the basement, protects the floors of the house from freezing. The base of houses on piles creates a single structure with soil protection, which does not let in cold air, maintains an optimal temperature at any time of the year.
- Aesthetics. The presence of a covering under the walls of the building allows you to visually complete the work and create a complete picture of the finished house. The blind area is also used as a path, you can place stepladders on it, use it to create a resting area, a base for installing stairs at the entrance, or connect it to the path on the site.
- Root protection trees and shrubs. Large plants are able to penetrate the foundation with their roots; as they grow, they destroy it and create cracks that extend to the walls. The blind area of houses on a slope is slightly wider and thicker than their counterparts on a flat area; it creates a sufficient barrier for trees and bushes.
After the plinth cladding is finished, work on the blind area’s construction starts. In certain instances, where the foundation protection features an irregular, stepped form, the initial layers may be created prior to the coating appearing on the building’s base.
The photo’s blind area surrounding the house on a sloping site:
Features and Requirements
The primary feature that sets apart a blind area for a building situated on an incline is the requirement for storm drainage installation. Concurrently with the protective coating trench, the gutter trench is laid.
What other conditions need to be fulfilled:
- the width of the blind area is at least 1 meter, since uneven areas are subject to accumulation of precipitation, according to SNiP, the protective layer should be 20 cm higher than the level of the roof overhang;
- trench depth 45 cm for covering with insulation (used most often in central Russia);
- the slope of the coating on an uneven area is the maximum possible – 10%, this is especially important for steep hillocks and lowlands, thanks to the slope, moisture is removed from the building quickly and does not linger even during heavy rainfall.
Being on such a blind area during frosty conditions can be dangerous, so either cover it with sand or avoid using it for passage.
Prior to beginning work, a marking process is followed. There are two methods for creating a blind area on a slope:
- Solid. Straight design, the ground is pre-leveled as much as possible, soil is added where necessary, holes and irregularities are brought to the same level. Then they dig a trench and begin assembling the “pie”.
- Stepped. Marking is carried out on each individual section of unevenness, each square is dug separately, and formwork is installed. The result is a multi-level structure, possibly with several platforms. There is no need to level the site, each element is combined with the neighboring one, they are hermetically connected, there are drainage systems, storm sewers and a drainage system.
The particular landscape determines which approach is best. A step system is advised for intricate variations in ground level; however, the installation process is more difficult in this case. You can complete the full version more quickly and easily on your own.
Required layers and their sizes
Depending on the soil type, climate, and architecture of the home, there are various types of blind areas found on slopes. Differentiations:
- Concrete. This is a hard coating option, one of the most popular, does not require large financial costs, tolerates frost well, can be used in any region, can be created independently, without the involvement of equipment.
- Asphalt concrete. The principle of creation is similar to concrete, but the coating is expensive and special equipment is required for installation.
- Stone. Looks beautiful in the landscape, stands above average, preferable for regions where precipitation is not so frequent. On a slope you need to spend time to create it; installation of the coating is more difficult than on horizontal terrain.
- Bulk made of crushed stone, gravel, granite chips. This is a soft type of blind area, its installation is easier than hard. It is necessary to carefully consider the drainage system. Not recommended for use on slopes in the northern regions and central Russia.
- Paving slabs. A universal option, looks solid, great for buildings on a slope.
- Hidden blind area. The adjacent territory after the construction of the layers is covered with a lawn or perennial plants, shrubs, compositions with stones and crushed stone are installed, which do not look like a path, but merge with the site and landscape.
Layers of concrete, asphalt concrete, paving slabs, stone, or other hard blind areas that need insulation:
- geotextiles are laid on the prepared base, since the blind area on the slope needs enhanced protection from water flows, both external and underground, and there is also a high risk of ground movement;
- a layer of crushed stone 10 cm, smooth and compacted;
- geotextiles reused;
- sand cushion, moistened with water and carefully compacted 15-20 cm;
- waterproofing material, with an overlap on the base wall;
- insulation layer, thickness 10 cm;
- waterproofing repeatedly (use roofing felt or membrane);
- crushed stone, 10-15 cm, leveled;
- reinforced mesh.
The thickness of the concrete layer that follows is determined by the type of coating. If the structure is finished, it should be 10–12 cm; if tile or stone is on top, it should be 5 cm. After laying a 15 cm layer of asphalt concrete, you will need a 5 cm cement-sand mixture to lay stone and tiles.
Layers for insulated soft blind areas (crushed stone, covert material, concrete-free paving slabs):
- wet sand is laid on the prepared bottom of the trench, a layer of 10 cm;
- waterproofing with an overlap on the base wall;
- insulation layer 10 cm;
- waterproofing again;
- sand cushion 10 cm;
- geotextiles.
Additionally, based on the kind of coating. The final layer of material, which is 15-20 cm thick and can be either gravel or granite chips, is crushed stone.
Regarding paver slabs:
- crushed stone 10 cm,
- cement-concrete mixture 5 cm,
- finishing coat.
Regarding obscured blind spots:
- crushed stone 10 cm,
- geotextiles,
- lawn.
It is not advisable to use soft pavement on inclines in central and northern Russia. Only in warm climates with little precipitation and little snowfall, and on mild slopes.
Technology and stages of construction
On a sloped site, it is advisable to begin building a blind area prior to the roof being constructed. Water from the roof can fall on the coating rather than the bare earth because the canvas is at least one meter wide.
Phases of construction for a concrete-covered, insulated blind area:
- If possible, level the area so that the soil is free of holes. Thoroughly compact the poured soil and moisten it generously with water so that it settles.
- Place markings using pegs and thread. Start from the corners of the building, at a distance of 1 m. There will be a storm drain nearby; a distance of 15-20 cm must be left for it.
- Dig a trench 45-50 cm deep, level the bottom, compact the soil.
- Place geotextile on the bottom, sprinkle it with crushed stone (10 cm), level it, compact it. For better effect, it is recommended to use a vibration machine for compaction.
- Re-cover with geotextile. Lay a layer of wet sand at a slope from the plinth wall. It should be 8-10% per 1 meter of blind area width. The layer is 15-20 cm, can be laid sequentially, first 10 cm, compacted thoroughly, then another 10. After that, wet the sand cushion with a hose and tamp it again.
- Lay a layer of waterproofing (for example, roofing felt) on the sand with an overlap of 15-20 cm on the base wall. Treat joints with bitumen mastic, sealed.
- Lay insulation (for example, polystyrene foam) 5 cm thick in 2 layers. Treat joints with polyurethane foam.
- Another layer of waterproofing with an overlap on the base. 10 cm of wet sand on top, compact thoroughly, cover with geotextile.
- Crushed stone 10 cm, level, compact.
- Install the formwork (fix it motionless), form a damper joint between the wall and the blind area (it is 2-3 cm, it is needed so as not to damage the structure if the house shrinks). Place a 10*10 reinforced mesh inside.
- Place boards 5 cm high at a distance of every 2 meters across the width of the blind area. They form expansion joints to prevent the coating from cracking during use and shrinkage. Install beacons on 4 sides of each side of the blind area, which will indicate the required angle of inclination and the maximum level of the concrete mixture. Install intermediate auxiliary beacons every meter. Stretch the thread across the width of the blind area and lower it along the intermediate beacons so that the direction of laying the concrete mixture can be clearly seen.
- The first layer of concrete is poured taking into account a slope of 10% from the wall, each square separately. After covering the blind area with a protective film and wait until it dries completely, periodically moisten the surface with water to avoid cracks. Thickness 5-7 cm.
- At the corners of the building (and every 2-3 meters of the wall, if it is long), lay gutters for drainage. Pour a homogeneous finishing layer (install the gutters motionlessly into the mixture), step by step, starting from the top point, use intermediate beacons, layer thickness 5-7 cm. Level the surface using a rebar. Carry out ironing. Cover with a protective film, wait until it dries completely, and periodically moisten the concrete with water.
It is necessary to form a storm sewer ditch around the blind area’s perimeter after it has been created. The gutters’ size determines the depth, which is typically 15 by 15 cm.
The main mistakes during construction
Considerations:
- It is imperative to create a high-quality drainage system and storm sewer system. Install waterproofing, protection against moisture should be maximum. As well as from possible soil movement (for this, an additional layer of crushed stone is placed in the blind area at a slope at the bottom of the trench).
- It is necessary to observe not only the slope of the soil, but also the slope of the blind area. The degree here is higher than that of standard horizontal coating – 8-10%.
- The formation of damping and expansion joints is necessary in case of shrinkage of the structure or ground movement.
Prior to beginning construction, precise measurements are made, beacons are installed, and a thread is pulled to make flaws instantly visible. This process continues until building materials are installed.
Although it may appear difficult, building a blind area around a house on a sloped plot can be done effectively with a clear, step-by-step process. This tutorial will take you step-by-step through the entire process, from organizing and setting up the location to choosing the appropriate materials and carrying out the installation. Even on uneven terrain, you can guarantee efficient drainage and safeguard the foundation of your house by adhering to these simple instructions.
Prices for the arrangement of a path on a slope
The cost of constructing a traditional horizontal covering is marginally lower than that of installing a blind area on a slope. This is a result of higher material costs, more meticulous preparation, intricate calculations, and intricate installation. The type of future coating and the availability of insulation also affect the cost.
The average cost of an insulated, high-strength blind area on a slope is:
- Moscow and Moscow Region – 3700 r/mp;
- St. Petersburg and Leningrad Region – 3000 r/mp;
- Krasnodar – 2700 r/mp;
- Rostov-on-Don – 2500 r/mp;
- Kazan – 3000 r/mp.
This section contains a wealth of pertinent and helpful information regarding the blind area’s design.
Step | Description |
1. Planning | Determine the dimensions and layout of the blind area considering the slope of the plot. |
2. Excavation | Excavate the soil to the required depth, ensuring a uniform slope away from the house. |
3. Base Preparation | Compact the soil and add a layer of gravel or crushed stone for drainage. |
4. Formwork Installation | Set up wooden or metal forms to outline the blind area. |
5. Waterproofing | Apply a waterproof membrane or coating to protect the foundation. |
6. Reinforcement | Place reinforcement mesh or rebar within the formwork for added strength. |
7. Concrete Pouring | Pour the concrete mix into the formwork, ensuring an even distribution. |
8. Smoothing | Level and smooth the concrete surface using a trowel or float. |
9. Curing | Allow the concrete to cure properly, keeping it moist for several days. |
10. Formwork Removal | Carefully remove the formwork once the concrete has set and cured. |
11. Finishing Touches | Apply any desired finishes or sealants to the concrete surface. |
On a sloped plot, creating a blind area around a house can appear difficult, but it is completely doable with careful planning and execution. You can prevent water damage to your home’s foundation and preserve the aesthetic appeal of your property by following these simple instructions.
To make sure that water is diverted away from the foundation, start by evaluating the slope and designing the drainage system. A firm base made of compacted gravel will be created by excavating the area and preparing it. This will create a blind area. The waterproof membrane and the right amounts of concrete and sand will be laid down to form a strong barrier against moisture.
Taking care of the final details, like adding expansion joints and sealing the edges, guarantees that the blind area will hold up in all kinds of weather. This procedure improves the overall look and value of your house in addition to protecting it.
You can secure the foundation of your house while coming up with a beautiful and useful solution if you put in the necessary time and effort into this project. These easy-to-follow instructions will prepare you to take on the project and reap the rewards of a well-built blind area surrounding your home.