Good afternoon, dear guests!
The main task of the blind area is to drain water from the base of the building, and this can be done by any waterproofing material. The question boils down to another, how long it will last and how practical it will be in operation.
I made my decision to install a soft blind area at the stage of laying the foundation. Already then I purchased two rolls of geomembrane with all the building materials. The first one was applied inside the house - in a patty of floors on the ground, and the second I left to gather dust on a shelf in the barn, where it lay and waited in the wings.
Geomembrane is a dense profiled polyethylene material used as waterproofing in various fields. In my case, it will drain water from the house and be a hidden blind area. The manufacturer gives a 50-year guarantee for the material in close contact with the ground.
I made the choice between inexpensive materials from two competitors: TechnoNIKOL and Isostud. I stopped at Isostud, because at the time of purchase, there was a defect in the profile design in the rolls of Technonikol - in the conical extruded protrusions. Perhaps at that time, it was a technological defect in production and the bulges were pressed so strongly that through holes were formed in the material.
How did I like the hidden blind area?
1. Mounting
The installation of such a blind area is carried out several times faster than concrete work. For laying, you need to dig a trench deep into the bayonet of a shovel with a slope from the house:
Next, tamp the soil and add sand as needed (I'll explain why later) and spread the material:
Then, fill up with bulk materials with good throughput: crushed stone, coarse sand or pebbles:
I spent 2 days on the formation of a blind area with a slope: I dug it, spread it out, sprinkled it with rubble.
2. Finish coating
The top coat can be anything - taste and color! If you want - the same concrete, but what's the point? I'm going to make paving slabs from the front of the house, and there will be a lawn in the backyard - i.e. directly adjacent to the house a fertile soil layer.
This is done like this:
screening / sand with a layer thickness of about 5 cm is laid on the crushed stone, black soil is placed on top of the sand. Further, sowing with grass / flowers is performed. That's all - labor costs will be at most - half a day!
Thus, the topcoat can be anything and this is another huge plus for such a blind area.
3. Repairs
The third plus is that there is no need for repairs. I made a bed and forgot. The material is so dense that it does not deform from the upper layers of rubble. The main thing is an even base.
Now, I have already started laying the curb:
In order not to get the impression that the blind area will be a trough for water - below is an illustration showing the entire structure in section (I draw two options):
Water entering the blind area will go through the rubble away from the house. At the discretion of the owner, drainage can be done. But, for soils with good filtering ability, it is not necessary. The drainage system must be formed if the soil is clay or loam.
Financial question
One roll of 40 sq.m. costs ~ 4,000 rubles. The roll is 2 meters wide and 20 meters long. One roll, cut lengthwise, left for the entire blind area of the 8x10 house.
To date, the costs are as follows:
- Geomembrane - 4,090 rubles.
- Crushed stone - 2,000 rubles.
The rest of the costs depend on the topcoat. If it is black soil, then you will have to fork out accordingly only for sand and black soil, if it is a tile, then for screenings, tiles and curbs.
Disadvantages:
Due to its high density, the geomembrane is inelastic, therefore it requires an even base and the absence of sharp stones, which is why you have to add a thin layer of sand in places or remove the bumps to level surface. Otherwise, it can still leak under the significant weight of the upper layers of the backfill.
I only found one flaw! The rest is pluses :-)
I hope the article was useful to you!
Thanks for attention!
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