A private home’s blind area is an important safety measure in addition to being an attractive feature. Water seeping into the foundation could eventually cause major damage, so this concrete strip stops it from happening. For this area, creating the ideal blend is crucial to ensuring efficacy and longevity.
It is necessary to use the proper amounts of cement, sand, gravel, and water to create a dependable blind area. The strength and durability of the concrete are determined by the proportions of these ingredients. Any component used in excess or insufficiently can cause erosion, cracks, and inadequate foundation protection.
It’s important for individuals doing this project on their own to grasp the fundamentals of mixing concrete. You can build a sturdy blind area that will shield your house for many years by adhering to a few basic rules and paying attention to the ratios. Let’s examine the ideal ratios and a few pointers to achieve the greatest outcomes.
For durability and weather resistance, the proper concrete proportions are essential when building a blind area for a private home. Generally, a 1:3:5 mixture of cement, sand, and gravel works well. Water is added gradually until the right consistency is reached. This equilibrium guarantees that the concrete is both easily worked with during installation and robust enough to endure environmental conditions. It’s critical to fully combine these ingredients to prevent any weak points that might eventually cause cracks or other damage.
Quality of components of concrete mix
Sand, cement, crushed stone, and water make up the concrete for the blind area. Binders and fillers, which make up up to 70% of the solution’s mass overall, are also included in the composition. Increased strength and elasticity of the material are made possible by these additives.
When discussing the attributes that the constituents ought to possess, the subsequent suggestions ought to be emphasized:
- Sand should be free of any impurities (clay, silt and other substances). If this component contains at least minimal additives, then the concrete mixture will be heterogeneous.
- Crushed stone should not contain lime. The highest quality crushed stone is made by crushing river gravel. The recommended grain size is 5-20 mm. Also, instead of crushed stone, you can use gravel and plasticizing additives.
- It is recommended to use only running water for the mixture.
- Expanded clay is often used as a filler, which significantly reduces the weight of the future concrete structure.
Although there are no strict guidelines for cement, you should pay attention to its marking to ensure that the concrete you mix is of the highest quality.
Concrete marking
Concrete can have its compressive strength determined by marking it. Now let’s look at the most popular brands that are suggested to be used when building a private home:
Such concrete is rarely used for private construction because grades 100–150 are unsuitable for building street structures and grades M 400–500 are used for building multi-story buildings. Additionally, because compositions M 250 and M 300 have costs that are "an order of magnitude" higher, they can be deemed unprofitable. Concrete M 200 is the best choice for a blind area because of its excellent quality and reasonable price.
Proportions for concrete M 200
In order to independently prepare grade M 200 concrete mortar, the following ingredients must be mixed in a specific ratio:
- Portland cement M 400 – 287 kg.
- Crushed stone (size from 5 to 20 mm) – 1135 kg.
- Sand and gravel mixture (SGM) – 751 kg.
- Water – 186 l.
Practical! For a blind area, the typical ratio of sand, cement (M 400), and crushed stone is 1: 2.8: 4.8.
There’s also this other recipe:
- Cement – 287 kg.
- Sand – 803.6 kg.
- Crushed rock or gravel 1377.6 kg.
- Water – 186 l.
Practical! In general, the water-to-cement ratio (WC) is 0.65:1, however if the sand or sand-gravel mixture is excessively moist, this can be adjusted.
Cement should only be bought from reliable producers if you want the best mixture. The fact that PC only holds its properties for a maximum of three months (beyond which it loses up to thirty percent of its strength properties) should be considered. If you purchase a PC from a hardware store, make sure to look up the composition’s production date. If the package containing concrete only has the day and month on it, it is a fake. The marking needs to be done once every second. Two bags with the same markings per second are subject to the same rules.
Practical! Counterfeit cement composed of lime or dolomite is widely available these days. You run the risk of obtaining a subpar structure if you use such compositions to prepare the concrete for the blind area.
Preparation of concrete mix
Take the following actions to get a solution ready for the blind area:
- Pour clean water into a concrete mixer (an old bathtub, basin or bucket).
- Add cement and mix it with water until “cement laitance” (light-colored liquid solution) is formed.
- Pour crushed stone into the solution, wait 30 minutes and mix all the components again. The larger the crushed stone, the less water you will need to prepare the solution.
- Add sand and mix the mixture until you get a thick, homogeneous mass.
- Pour concrete into the formwork for the blind area.
Practical! It is advised to complete the task at a minimum temperature of +5 degrees. If you want to construct a blind area during the winter, you must warm up the concrete solution before pouring it.
To determine the amount of dry mix required, you must:
- Determine the total area of the blind area (to do this, multiply its length by its width).
- Multiply the resulting number by the height of the blind area.
- Add 15% to the resulting number (this is the stock of the mixture).
Thus, if the blind area has a 20 m 2 area and a 17 cm height, we obtain:
The amount of mixture you will need for the blind area is 20 x 0.17 = 3.4 + 15% = 3.9 m3.
It is advised to make concrete more water resistant if you reside in an area with a harsh climate and frequent rains. Penetron, Aquatron, or any other additive that increases moisture resistance can be added to the solution to achieve this. Additionally, ironing can greatly improve the surface’s resistance to moisture.
| Material | Proportion |
|---|---|
| Cement | 1 part |
| Sand | 2.5 parts |
| Gravel | 4 parts |
| Water | 0.5 parts |
| Optional: Plasticizer | As per manufacturer"s recommendation |
For the concrete in the blind area of your private home, proper proportioning is essential to long-term performance and durability. A sturdy barrier that will withstand weather and surround your foundation can be made of concrete by carefully combining the right amounts of cement, sand, gravel, and water.
Recall that a balanced ratio that offers strength without being overly rigid is frequently the best combination for this kind of project. This guarantees that the blind area won’t break or deteriorate in the face of temperature fluctuations and ground movement. A smooth, even finish can be achieved by using the proper proportions, which will enhance the area’s functionality and aesthetic appeal.
Ultimately, spending a little extra time to properly prepare your concrete mix can save you money on maintenance and repairs down the road. When done correctly, it’s a simple process that both protects and improves the appearance of your house. Thus, take great care when measuring, mix well, and relish the peace of mind that comes with a well-built blind area.
