How to make a reliable and durable soft otmostku

It is difficult to overstate the importance of the blind area, especially in areas with high groundwater levels and heavy rainfall. Nevertheless, for many it is still desirable, but an optional element. Last but not least this is due to the complexity of the classical monolithic device "pie". Relatively recently, there was simplified, with the least reliable variant of the blind area, which does not require cubic meters of concrete. Together with specialists from the company TECHNONICOL consider the most relevant aspects.

Content

• What is the blind area, and its purpose.
• What is soft blind area.
• The technology of the soft blind area.
• Participants' questions and answers portal specialists.

What is the blind area, and its purpose

Otmostka - one of the most important structural elements of a building, which is a strip of the impermeable coating extending around the perimeter near the base.

The main object of the blind area is an abstraction of water from the foundation and preventing blotting ground in this area, and further - and freezing.

Without the foundation of the blind area is regularly in contact with moisture, which will adversely affect its strength and durability.

In addition, when heavy rain no blind area will contribute to the pollution of the facade. Also, the coating performs the function of the pavement on which in any weather, you can move around the building. As for the aesthetic side of the issue, the house, the blind area edged, looks much more attractive and becomes a finished appearance.

Alex Tsybenko (Senior Technical Specialist direction "Engineering waterproofing" Technical Directorate TECHNONICOL Corporation)

Unfortunately, the importance of the blind area is often underestimated, not all builders are paying her enough attention. A holder may further encounter with such negative effects as a crack on the facade of the building. When otmostka offline, rainwater and melted water may naturally accumulate at the base of the foundation. In addition to direct damaging effect to the base structure may take place and heaving soils fraught deformations.

What is soft otmostka

As usual, well insulated blind area is of two kinds:

• monolithic;
• soft.

In the first case, the coating with a continuous, concrete finishing layer in a second, opposite - permeable coating, but with a sealed base. Monolithic (hard) otmostki usually concrete or asphalt, the same can be soft like a gravel layer, and with tiles laid floating manner, sometimes even sward grass. Rigid otmostka drains water from the final inclined surface on the soft water freely permeates through the upper layer and penetration of the soil prevents the waterproofing layer, from which it is removed in drainage.

The most popular kind of soft pavings on heaving soils, so in most cases they are insulated, on the basis of sheet Epps. However, doing without warming, when the choice is not dictated by the need to prevent the swelling, and the desire to simplify the process.

zip (party FORUMHOUSE)

I do not want to mess with the pouring of concrete blind area, and the final result of the eye, for sure, is not happy. I want to make a simpler sand bed, on top of the waterproofing, and the top, with a slight slope - paving tiles. It happens as if a blind area, and track.

chicken (party FORUMHOUSE)

The idea is correct. Such a method is now often used. As used waterproofing layer is thick (about 0.6 mm) of the membrane from the high pressure polyethylene. In possible not only to lay tile as an upper layer, but pour gravel, pebbles, grass sowing, etc.

However, the standard soft cake blind area includes the following layers:

• training;
• insulation;
• waterproofing;
• drainage;
• geotextiles;
• topcoat.

The minimum width of such a blind area is 60 cm, the maximum depends on the eaves of the roof - the coating should protrude from it by 15-20 cm. On the heaving soils it is recommended that the web is not less than a meter wide. The depth depends on the soil type and the presence of insulation, and on species topcoat, but the average is 30-40 cm.

The technology of the soft otmostki

The main element of the blind area is soft waterproofing - it must be strong enough to support the load of drainage and topcoat. Geotextile prevents mixing of drainage and topcoat, which is fraught with silting and deterioration of the capacity, so it is important also not to be underestimated. Today, manufacturers produce special bilayer membrane - the profiled base of High Density Polyethylene (HDPE) and thermobonded geotextiles.

Geotextiles attached over the "spikes" of polyethylene base, provides filtering and quick water drainage. That is, one membranaodnovremenno and waterproofing and drainage, and geotextiles, which greatly simplifies installation.

In addition, it may be beneficial.

Alex Tsybenko

The bilayer membrane not only instantly removes filtered liquid from the foundation, but also simplifies the choice of topcoat. Why expensive coverage that you can make dumping gravel or fall asleep fertile soil and sow a lawn grass? Polyethylene, from which it is made, it is impossible to damage the plant roots.

soft otmostki device technology based on such a membrane is not complicated special operations.

Training

The soil chosen to the desired depth, leveled, tamped. Perform podsypku building sand layer with a gradient from the walls, if the soil is strongly bulk, instead of sand is sometimes used compacted clay.

Warming

Over the riprap placed slabs of insulation to prevent freezing of the soil under the blind area. Since the top of the insulation and the membrane will still finish layer, additional fixation is required.

waterproofing

membrane rolled along over the insulation, the geotextile layer up, overlapping the wall 15 cm over the edge sunset and heater so that it is fully closed and Epps, and a sandy base. For sealing coating membrane overlapped segments - are separated from the spikes geotextile membrane layer and fixed to the pieces four spikes (at least 10 cm), tightly inserting them into the slots. All seams are desirably a special double-sided glue tape. Then return to the place of geotextile, and the joints are also sized tape not less than 50 mm wide. After stacking the membrane is fixed to the wall by means of special fasteners, some members of our portal use mastic.

finishing layer

Above the membrane is filled gravel or soil substrate, under tiles or natural stone poured sand layer. Border used in gravel packing or tile / stone.

Answers to questions from participants experts portal

Soft blind area are quite popular among our craftsmen, and their device often experience various issues. Who else but the experts will give detailed answers.

Kosmos02 (party FORUMHOUSE)

For soft otmostki I bought another drain pipe, but on the edge, to collect water from the membrane, not laid, as suggested initially. I thought so when I have a tile from the roof of the pipe with a funnel, on the open tray (with the grid), the water will go to the edge of the blind area in the same tray. And with the trays in a certain point "A" to gather, where in a ditch, too open pit top. That is, it turns out all the water from the roof will be 100% to leave and not to fall on the blind area. Water remains a driving rain that falls on the tile: Part of it will flow down on the tile in the tray on the edge otmostki already well, and part will penetrate through the joints, gravel and sand the membrane and slide into 1.7 meter from foundation. So maybe you should not be afraid of the water and do not drain pipe to her collection?

Alex Tsybenko

That's right. Drainage of water falling from the roof onto a soft otmostku, several methods can be arranged:

"Open" surface water removal, through the already mentioned trays, which can be formed as molded plastic and concrete products. Such a system for collecting and transporting water coming from the roof of the blind area, allows minimize its spread over the surface of the blind area, and this, in turn, saves coating durability.

"Closed" retraction without application of special products, above. Water entering from the roof at the blind area is discharged by the drainage surface of the membrane, the edge of which can be coupled with an annular drainage site or with near-wall drainage of the foundation, or just conjugate with the local area area, where water abstraction and produced in the same way as with a classical surface concrete blind area.

Experts note that, thanks to the variety of surface water disposal options, including, atmospheric water (slanting rain) can be dispensed from the application of drainage tubes at the blind area device.

Mitroshka (party FORUMHOUSE)

Studying options offered soft blind area. Here explain to me the following: on the proposed schemes waterproofing layer is laid with a slope away from the foundation and, at best, case falls into the drainage ditch, and in most embodiments, finishes, or even slightly rises up trough. And all this at a depth of 30 cm. Those. instead of having to divert rain water to the side, we have it through the sand and rubble driven into the ground to get the waterproofing and water okolofundamentny lions?

Alex Tsybenko

Viewed embodiment soft otmostki using membranes involves the formation of drainage slope from the walls of the building at least 3 ° for the organization of the drainage coming to the surface of the blind area. It is thanks to the slope of the earthen foundation formed when laying the profiled membrane water that falls on their surface, it flows freely. The distance that the removed water, equals the width of the blind area is usually 800-1000 mm, but in any case this distance spans the width of filled sinuses pit. Thus, water is "reset" to the adjacent house portion (if not provided with water collecting arrangements falling from the roof onto otmostki surface such as a plastic sewer system or conjugation drainage membranes with annular or near-wall drainage). Therefore, neither of which "okolofundamentnom ditch with water" here is, by definition, nothing to say. Therefore, as natural, houses adjoining portion primer does not belong to pristennyh nor prifundamentnomu space.

Mitroshka (party FORUMHOUSE)

When the waterproofing goes into the drainage ditch, covered with gravel in the spring, all this rubble is monolithic block of ice, and the drainage is not working, ie at a time when the groundwater level as high as possible, such a blind area, again, not working?

Alex Tsybenko

Example otmostka external walls of the building is not formed to protect the foundation from groundwater, and to protect the foundation from atmospheric water (rain, melting snow) so otmostku assign to protect the foundation from groundwater, irrespective of their occurrence, meaningless. In the case where the drain soft membrane blind area is associated with dusting of wall or annular drainage, drainage from the surface is carried out, regardless of the season. Plastic drains into the drainage trench located below the frost line. For Moscow, for example, the depth of freezing, depending on the soil, varying from 120 cm to 132 cm clay sand. Water in plastic drains located at this level, not only does not freeze, but also freely transported to the place of the slope catchment.

Mitroshka (party FORUMHOUSE)

GI can put on the ground surface (of course, with a bias), but then, as she lay paving slabs? Sprinkle sand on top and put the tiles, in my opinion, will not work, because in the rain water will wash away the sand from under the layer of tiles GI. Ie, under the condition of "no cement" remains an option simply Coating layer of gravel on the GI?

Alex Tsybenko

It is thanks to the special shape of the front surface drainage membranes, made in the form of "spikes", and attached to it a layer geotextiles, soft blind area on their bottom provides stability underlayment (sand, sand-gravel mix) under the sidewalk tiles. The combination of rigid drainage core in the form of pins geotextile membrane and forms a base layer for the tiles (sand, sand-gravel mixture) rainwater-wicking layer. Water entering the level of drainage geotextile membrane does not flow over its surface, and filtered therethrough, falling on the membrane layer, and is discharged through it (between the "spikes"). It is important that, at the time of water filtration through a layer of geotextile attached to the "spikes" of the membrane even the most fine particles of sand "no slip" through it, because its pores are smaller than the size of the smallest particles ground.

I.e, drainage membrane in the construction of flexible otmostki provide multiple functions:

• stability of the underlying layer of tiles;
• filtering water trapped in the backsheet;
• water abstraction;
• waterproof blind area.

Mitroshka

Epps is possible to insulate the ground under the blind area, but the insulation works both ways, and if, in spite of the our efforts, the ground under Epps still chilled, then in the spring thaw, he will be greatly longer. Those. We can get under the blind area "permafrost"?

Alex Tsybenko

If the foundation has a penetration less than the depth of soil freezing, the foundation for the protection of forces frost heaving soil in winter in soft otmostki system provides a use of insulation Epps. This avoids the occurrence of cracks on the base resulting from frost heaving of the soil. The problem of insulation in a blind area - change the distribution of temperature field, ie, move the isotherm negative temperature as far as possible from the walls of the foundation. The presence of negative temperatures and freezing of the soil under the insulation is not possible, the whole thing is how close or far away from the foundation wall will stop freezing. Therefore, the presence of a negative heater temperature is not critical. A correctly selected width and thickness of insulation insulation completely eliminates freezing of soil in the bottom of shallow foundations.

Soft blind area is considered to be the best option for heaving soils, but is also suitable for other soils if there is no desire to spend the time and effort to concreting or captivating visual component. But, regardless of species, blind area - an important structural element, which should not be neglected.

Lightweight otmostka pebbled will look great the house in the Scandinavian styleIt will protect and keramsit monolith. In the video - an insulation cap and a blind area Epps.