DIY waterproofing strip foundation

The main principles of moisture protection

Before talking about moisture protection technology, a few words should be said about the basic principles that should be followed, no matter which method you use. The list of the most important requirements is as follows:

take care of the maximum density and tightness of the insulating layer - it must be solid and not have cracks, tears and holes;

Monolithic (slab) block has the ability to absorb water, as a result of which you can get a low-quality base

where there is reason to believe that groundwater is most active, provide additional protection;
a well-made blind area will take on the negative impact of atmospheric precipitation;
if the groundwater passes close to the surface, take care of the installation of an additional drainage layer, which will lower the water level underground and prevent the destruction of the slab;
when choosing the material with which the slab will be waterproofed, pay attention to the height of the foundation.

If you want your building to stand for many years, observe these requirements when installing hydrophobic protection

This is critical for your efforts to be successful and make sense.

Performing the necessary work

Experts use several types of building insulation, each of which has its own characteristics and nuances

Experts use several types of building insulation, each of which has its own characteristics and nuances. Waterproofing is:

• horizontal;
• injection.

Horizontal waterproofing. At the initial stage of the work, the basement of the house is isolated from the foundation itself. This process is carried out using roll material, which must be laid out on top of the base. For work, it is recommended to use bituminous mastics, which are based on polymers. The mastic is combined with sheet polymer-bitumen material. It is laid with an overlap and pressed with a joint roller, the roller is preliminarily impregnated with mastic. Horizontal waterproofing provides a strong layer of protection between the foundation and the brickwork.

Injection is based on the formation of a membrane that repels moisture from the foundation

Injection is based on the formation of a membrane that repels moisture from the foundation. This waterproofing between the foundation and the plinth is carried out by injection and injection of a hydrophobic gel. Once the gel hits the base, it hardens and closes the pores in the wall and soil. Most often, this method is used to eliminate errors and errors in construction.

Before using the injection, examine the surface from the outside and from the inside. Next, small holes are made and polymer tubes with installed taps at the ends are introduced into them. The taps are connected to the system and everything is poured with gel under pressure. At the end of the entire process, the tubes are removed, and the entire area is covered with a layer of moisture-resistant plaster. It will not be possible to carry out such work on your own, tk. this will require the use of specialized equipment.

If it is not possible to create conditions for protecting the building from moisture from the outside, it is necessary to provide such measures from the inside. For the work, the same materials are used as for horizontal insulation

When protecting the structure, special attention is paid to the corners and joints. Experts recommend to additionally glue them with reinforced insulating tape.

Performing brick insulation measures is mandatory, even if your site is located at a low water table.

Features of proper concrete care

Proper maintenance of the concrete structure involves providing optimal conditions for hardening. They depend on climatic conditions, type of cement, type of product, etc. How many days does concrete need to be watered? This indicator is determined by the rate of solidification of the mixture for the following types:

• a structure made of slowly hardening cement needs to be wetted for about 4 weeks;
• products on Portland cement - 2-3 weeks;
• systems made of fast-setting alumina concrete take about 8 days.

On the first day after pouring, it is better to cover the foundation with burlap or wet sawdust in order to protect it from overheating and slow down the evaporation of water.

Waterproofing the strip foundation when pouring. Concrete strip foundation

The final stage in the manufacture of the strip foundation is its concreting. Asking the question of how to fill the strip foundation, one should understand two things: firstly, this is the quality of the concrete mixture, and secondly, the solidity of the structure. Let's start with the quality of the concrete.

• Without a concrete mixer, it will not be possible to prepare a high-quality mixture of crushed stone, sand and cement - a person simply cannot efficiently and quickly shovel these ingredients by hand. finished form and in the required quantity. This is the simplest and most acceptable option, which will allow you to fill the foundation quickly and end up with the necessary monolithic structure, and you will have to work with a concrete mixer for several days, and as a result, the monolith will not work.

If you nevertheless decide to fill the strip foundation with a self-prepared mixture, then you need to know the correct proportions of concrete. If we proceed from the number of buckets loaded into the concrete mixer, then for one batch you will need a full bucket of cement, two buckets of sand and gravel, and somewhere between 0.5-0.8 buckets of water.

To prevent cracking of concrete, special plasticizers are added to the mixture. If you prepare concrete the old fashioned way, then instead of plasticizers, you can add a couple of spoons of the cheapest washing powder to each batch.

How to fill a strip foundation

Do not lose sight of the process of concrete hardening - it should not happen quickly.

The slower the concrete hardens and then dries, the stronger it becomes. In another way, this rule of concreting can be voiced as follows - the strength of concrete directly depends on the moisture absorbed by it during the solidification process. Therefore, pouring the strip foundation with your own hands is accompanied by a number of subsequent actions:

• Firstly, immediately after the end of pouring, all the concrete must be covered with polyethylene - this step will reduce the evaporation of the liquid and allow the concrete to harden for a long time. Secondly, once a day for the first three to four days, the film must be removed, and the foundation is abundant. fill with water. Naturally, after filling with water, the cellophane must be put in place.

After a week, the formwork can be dismantled and the foundation can be left open to gain strength. Depending on the depth of the strip foundation, the direct construction of the house can be started no earlier than a month after the end of the pouring. In hot weather during this month, a self-made strip foundation must be abundantly moistened at a frequency of at least a couple of times a week.

When, after pouring the foundation, it can be treated with bitumen. Bituminous compositions

A budget and easy-to-apply method of waterproofing the foundation, which led to its popularity.It is necessary to process the walls of the foundation completely with bituminous mastic, pay special attention to the joints and possible cracks.

Advantages:

• Low cost;
• Ease of application;
• Elasticity.

Disadvantages:

• Quite a long time to complete the work (you need several layers and you need to wait for each layer to dry);
• Not the best hydraulic resistance;
• Short service life (after about 10 years, re-processing will be required).

The process of applying bituminous mastic is simple:

1. Surface preparation. The concrete surface must be free of soil and fragile concrete layers. Caverns and crevices must be filled with cement plaster. The surface must be dry to continue working.

The moisture content of the concrete base before applying the mastic should not exceed 4%. Otherwise, the mastic will flake off. It's easy to check: we take a piece of plastic film, meter per meter, and lay it on the foundation, if there is no condensation on the film in a day, you can start applying the mastic.

1. Primer treatment. To achieve better adhesion, the substrate is primed with a bituminous primer. One coat of primer is applied and an additional coat at the joints.

You can make a bituminous primer yourself. It is necessary to dilute BN70 / 30 bitumen with a solvent, for example, gasoline, in a ratio of 1: 3.

1. The bitumen needs to be melted. Melt the amount of bitumen that you can apply before it hardens: reheating of the bitumen leads to a partial loss of its properties. Hot bitumen is applied in 3-4 layers. For foundations buried up to 3 m, the thickness of the bitumen layer should be 2 mm, buried 03 to 5 m - 2-4 mm.
2. After applying all layers of bitumen, it is necessary to protect the waterproofing from mechanical damage. For such protection, you can use rolled geotextiles or EPS insulation.

1. Reinforcement of bituminous insulation is mandatory for:

• Cold seams;
• Joints and abutments;
• Over cracks and damage.

Most often, fiberglass is used for reinforcing bitumen.

Fiberglass is laid over freshly applied bitumen (while it is still liquid). For better adhesion, it is recommended to roll with a hard roller. After the mastic has dried, a layer must be applied that completely covers the reinforcing fiberglass. Fiberglass is laid with an overlap of 10 cm.

At junctions close to 90, you will need to use a fillet. This is necessary so that the waterproofing layer at the joints does not peel off from the base.

Reinforcement of bitumen in places of cracks and abutments significantly extends the life of the waterproofing.

The technology of laying timber on the foundation

The lower crown can be attached to the foundation in two ways: from above or from below. In the first case, the fasteners are made with anchor bolts. Through holes are drilled in the timber. Holes are also prepared in the concrete foundation at appropriate locations. Their depth is matched to the length of the anchor bolts, taking into account the section of the bar.

The moisture insulating layer will be damaged in the drill holes, therefore, before laying the first row, it makes sense to apply an additional amount of mastic at the fastening points.

Fixing from below implies the use of embedded elements installed at the stage of pouring the foundation. Threaded threaded rods and rebar pieces can be used.

When, after pouring the foundation, you can lay a brick. How long after the foundation is poured can the construction continue?

Any structure made of concrete or cement mortar, before starting other construction work related to the load on this structure, must be kept for a certain time in the state of "pouring" without loading.

After pouring, the concrete structure goes through several stages of polymerization: setting, hardening and final curing. At the same time, during the setting time of the concrete, further construction processes can be planned: the construction of walls, partitions and the installation of the roof.

What determines the rate of concrete hardening?

Factors that affect the rate of polymerization and hardening of concrete:

• Ambient temperature;
• Ambient air humidity;
• Direct or glancing sunbeams;
• Concrete grade;
• Additional measures: wetting with water, adding special additives, warming up in winter, covering with polyethylene, etc.;

The polymerization of concrete can be described as a complex natural process associated with a set of strength and drying, which can be corrected. Polymerization of concrete consists of the following stages:

• Grasping. At an ambient temperature of 20 ° C, the volumetric setting of concrete begins two hours after preparation and pouring of the mixture, it will last exactly the same period of time. When the temperature drops to 10 ° C and below, the setting process is significantly lengthened and can be from 20 hours or more;
• Hardening. For private concrete structures poured and maintained at a temperature of 15 to 20 ° C and a relative humidity of 75%, the curing process takes at least 3 days or 72 hours, after which other construction work can be started;
• Strength gain. This is a long-term process, depending on the "power" of the cast structure, which can last from several weeks to several years.

How long does concrete dry?

• Seasonality of filling. Depending on the specific ambient temperature and relative air humidity, the setting period of concrete can be from three days in summer and one month in cold weather;
• Rammer. In this case, the rule applies: “the higher the density of the filling, the faster the processes of hydration (hardening) proceed. In construction companies, ramming is carried out with special installations. In private construction by dense "bayonetting" with a shovel or hand tamping.

What materials should be used

When the question is whether it is necessary to waterproof a strip foundation and what is the best way to protect it, it is necessary to proceed from such factors as the structural features of the base itself and the entire building, the type of soil, operating conditions, etc. There are many materials on the market today and it will not be difficult to choose the most relevant option.

Foundation waterproofing materials:

• Roll (they are also gluing) - produced in the format of films, membranes, bituminous sheets, mounted on a layer of mastic or by heating, landing on glue (already applied to the sheets).
• Coating - bitumen, cold mastics, various compositions for application in liquid form, followed by solidification.
• Penetrating - sprayed or applied with a brush, absorbed into the concrete monolith, followed by crystallization and filling its pores, which makes the concrete resistant to moisture.
• Injection - similar in action to penetrating ones, they are applied by drilling holes in concrete and then distributing the composition under pressure, due to which the monolith is impregnated and strengthened from the inside.
• Painting - liquid polyurethane foam, liquid rubber can be used, which completely solidify after application and create a water-repellent elastic film. They do not last long, but they are easy to apply.

Waterproofing the bottom of the foundation. What types of waterproofing are used to protect the foundation

In order to prevent the negative impact of moisture on the foundation, the following types of waterproofing and other construction and installation works are used:

• Giving structural materials additional water-repellent properties.
• Creation of waterproof coverings on the vertical walls of the foundation, from its sole to the upper edge of the basement.
• Reliable waterproofing of horizontal inter-level joints, preventing capillary penetration of moisture upwards.
• Reliable protection of the waterproofing itself from external mechanical influences.
• Measures for warming the foundation and basement, reducing the negative effects of negative temperatures.
• Drainage system around the house.
• Creation of a reliable drainage system for rain and melt water - drain and storm sewer.
• Providing reliable ventilation in basements and basements.

The proposed figure shows, as an example, a possible general scheme for waterproofing the foundation of a building:

On the diagram, the numbers indicate:

An approximate foundation waterproofing scheme

1 - the sole of the foundation, which usually rests on a compacted sand and gravel cushion. Between it and the vertical wall of the foundation (2), there must be a cut-off horizontal waterproofing (4), which overlaps with an insulating layer arranged in the basement floor (4) between the base and the screed.

The outer vertical wall has a coated waterproofing coating (5), additionally protected by a waterproof membrane (7) and covered with a layer of geotextile (8), which protects against abrasive and other mechanical effects.

The upper edge of the basement (foundation wall) is also necessarily closed with a waterproofing roll material (6), on top of which further construction of the walls and floors of the building will be carried out.

To remove moisture, a drainage system is provided - pipes (9) laid along the perimeter at the level of the foot of the foundation in a gravel cage. For a more reliable protection against the ingress of water from atmospheric precipitation into the depths of the ground, it is advisable to arrange a clay castle around the house (10).

In areas with a harsh climate, strong freezing of the upper layers of the soil, or in the case when it is planned to place residential or utility rooms in the basement or basement, the foundation and basement waterproofing system is supplemented with a system of their insulation:

The diagram in general terms repeats the one that is placed above, therefore the main numbering of parts and assemblies is preserved. In addition, shown:

Foundation waterproofing scheme with additional insulation

1.1 - sand and gravel cushion under the bottom of the foundation. This layer can also be made of lean concrete with coarse graded filling.

12 - insulation panels made of extruded polystyrene foam, installed outside on top of roll waterproofing along the entire height of the foundation and basement walls.

13 - plastering layer of the basement finish. Currently, instead of it, special basement thermal panels are often used - they provide both insulation and reliable cover from direct exposure to water.

14 - erected wall of the building. The figure clearly shows that it begins to fit necessarily from the horizontal cut-off waterproofing layer of the foundation.

The choice of a specific type of waterproofing, and hence the materials used for it, largely depends on the specific purpose of the room located in the basement. The existing classification (according to the BS 8102 standards adopted in Europe) divides them into four classes:

• The first, lower class is ancillary or technical premises that are not equipped with power grids. Wet spots or even small leaks are allowed in them. The wall thickness must be at least 150 mm.
• The second class also includes technical or utility rooms, but already equipped with ventilation, in which only humid vapors are permissible, without the formation of damp spots, with a wall thickness of at least 200 mm. It is already allowed to install electrical appliances of standard mains voltage here.
• The third class is the most common, and most of all of interest to individual developers. It includes all residential buildings, offices, retail outlets, social facilities. The thickness of the walls should not be less than 250 mm, a system of natural or forced ventilation is required. No moisture penetration is allowed.
• As a rule, you don't have to deal with the fourth class of premises when building your own house - these are objects with a specially created microclimate - archival storages, libraries, laboratories and others, where special requirements are imposed on a constant, clearly established level of humidity.

Types of waterproofing works

Waterproofing the foundation of the coating with mastic before laying bricks

Measures to protect the foundation from moisture are divided into types:

1. Waterproofing coating. Such protection is carried out with organic binders (bitumen, mastics and emulsions based on them with special additives) and polymer compounds. They can be applied either by hand, with a roller or brush, or with a special gun using compressed air. Lubricants are very thick and should be thinned with solvents or heated to a liquid state before use, as recommended by the manufacturer. Such compositions are usually delivered to construction sites in buckets or barrels.
2. Oleechnuyu insulation. As a rule, these are materials based on polymer fabrics or paper, impregnated with compositions with organic binders. For ease of transportation and storage, they are produced in the form of rolls. Before application, the roll is unwound, the waterproofing is cut out, after which it is applied to the concrete structure. During the production of work, so that such material adheres to the surface, it is heated with a gas burner so that the binder on the mounting side becomes liquid, after which the material is applied and leveled with a roller or trowel, removing dents and removing excess air from under the material. The glued insulation is more reliable and durable than the coated type, since it does not wear off during the seasonal movement of the ground, thanks to the use of a fabric frame, which makes all the insulation a single rigid element.
3. Processing with liquid glass. For such protection, a special composition is used, which includes water-soluble substances based on quartz sand. When applied, such a composition penetrates deeply into the pores of the concrete, and after hardening, it forms a strong protective layer, on which additional insulation can be applied. It is not recommended to use such formulations separately, since they dissolve when exposed to moisture.

If you add liquid glass to concrete during its preparation, then the mixture after hardening will better resist the effects of moisture, since the additive will slow down its penetration into the depths. However, this will reduce the strength characteristics of the concrete structure, for which it will have to be reinforced with reinforcement. This option is well suited for lightweight structures such as a bathhouse or shed.

What materials should be used

For a properly executed waterproofing of a room, it is necessary not only to know the work processes, but also to understand building materials

For a properly executed waterproofing of a room, it is necessary not only to know the work processes, but also to understand building materials. It is on them that the quality of the waterproofing work performed and the life of your house depend. Experts divide materials into three types:

• pasting;
• coating;
• impregnating.

The glue material is not able to protect the house for a long time, because in the process, roofing material or polyethylene is used. Over time, this material breaks down and can begin to leak moisture.

The coating waterproofing of the walls has a longer service life, and it is also more conveniently fixed on the surface of the masonry. Bitumen, moisture resistant paint are used as the material, they are applied with a spray gun or a brush. Before processing the entire plane, it must be cleaned of excess debris and dust.

The impregnating material is one of the most effective and high quality materials. They are the usual Penetron dry mix, which is diluted and applied with a brush.The mixture contains special additives, which, in close contact with moisture, turn into strong and insoluble crystals. Penetrating waterproofing for masonry is of great importance and has a strong effect for indoor and outdoor applications. After applying the material, there is no need to dry it. Thanks to the water-resistant surface, it is not afraid of scratches, and the formation of mechanical damage will not reduce the effect of moisture resistance.

Strength set with concrete

Concrete is an artificial stone that is obtained from a solution prepared in special proportions. The hardening of the mixture depends on many factors, so there is no exact answer, suitable for all cases, to the question of how long the foundation of the house should stand after pouring. The answer is individual for certain conditions.

On average, it is believed that curing takes 28 days, but this value is an average. The process depends on the following factors:

• what type of cement was used when mixing the concrete solution;
• the ratio of cement and water in the mixture;
• ambient temperature during foundation hardening;
• what the weather will be after pouring (sunny, cloudy, windy);
• how compacted the concrete solution is.

Each of these factors has an impact. The whole process can be conditionally divided into two stages:

• grasping;
• hardening.

Grasping

This is the period during which the foundation mix remains mobile. This means that the entire process of transportation, filling and sealing must fit within these frames. When delivered with concrete mixers, the setting time is increased due to constant stirring. If the solution is in the mixer for too long, changes occur that will adversely affect the quality of the finished structure. The setting period is inversely proportional to the ambient temperature.

The optimum temperature is 20 ° C. Quick curing at high temperatures can adversely affect the quality of the foundations of the house after pouring.

Hardening

The second stage of strength development is hardening. If the time of the first stage dictates the conditions for performing the work, then how long the hardening will take will affect the possibility of continuing construction and moving on to erecting the “box” of the building. The table below shows the values ​​of "holding" of the foundation after pouring, depending on the temperature. For 100% of the set of compressive strength, the value that will be obtained at a temperature of 20ᵒC is taken, if the foundation is allowed to stand for 28 days. The values ​​are given for the material of grades M200-300 (class B 15 - B 22.5) manufactured on Portland cement grades M400-500.

The table shows that negative temperatures especially slow down the process.

Strength graph of concrete versus temperature.

The stripping strength of concrete is determined by the joint venture "Bearing and Fencing Structures" and is 70% of the brand (safe start date of work). This means that it is necessary to remove the formwork after pouring the foundation of the house at least after 7 days for an average daily temperature of + 20ᵒС or at least 14 days for + 10ᵒС. With appropriate justification, it is possible to withstand the time until reaching only 50% of the brand compressive strength (normatively safe start date) before removing the formwork. When self-erecting, it is also recommended to familiarize yourself with the "Guidelines for the production of concrete work in winter conditions, the regions of the Far East, Siberia and the Far North."

The curing time of the foundation also depends on the type of Portland cement used to make the mixture. There are three types:

• fast hardening;
• normally hardening;
• slow hardening.

The table shows the values ​​of the compressive strength for concrete on various binders, depending on the air temperature. All values, as in the previous table, as a percentage of the strength at a temperature of 20 ° C, if the monolith is allowed to stand for 28 days.

In the same way, the formwork is removed at a gain of 70% of the brand compressive strength (50% under special conditions).

Waterproofing methods

There are two main methods of waterproofing a strip foundation - horizontal and vertical methods, each of which is performed according to a specific technology, using certain materials.

Horizontal

It is necessary to think about how to make a horizontal strip foundation waterproofing even at the design stage of the structure. Preparatory activities can take up to 17 days (in addition to the main work). Horizontal insulation protects the foundation from capillary groundwater in the appropriate plane. Necessarily includes a drainage system, equipped with a high groundwater level.

A solid foundation is made under the tape, a waterproofing layer is mounted on it. Often for this, a pillow is created that is thicker than the future foundation. The easiest option (suitable for a bathhouse, garage, etc.) is to make a cement and sand screed in a 1: 2 ratio.

Horizontal waterproofing technology:

• Backfilling the bottom of the pit with sand with a layer up to 30 centimeters thick, tamping.
• Filling the pillow with a cement screed with a layer of 6-8 centimeters, hardening within 2 weeks.
• Coating the screed with bitumen mastic, installation of roofing material over the bitumen layer, repetition of the layers of mastic + roofing material. A cement screed is poured on top with a layer of 6-8 centimeters, solidification.
• Foundation construction.

In some cases, drainage may be necessary: ​​if the depth of the structure is lower or at the level of the groundwater, when the permeability of the soil is low and moisture can accumulate in it.

Drainage performance:

• At 100 centimeters from the base, along the perimeter of the structure, a pit is being dug up to 30 centimeters wide and 25 centimeters deeper than the depth of the foundation. The pit should have a slope towards the catchment area, where water will accumulate.
• Covering the bottom with a layer of geotextile with an overlap of it on the walls by at least 60 centimeters.
• A layer of gravel 5 centimeters thick is laid.
• Installation of a drainage pipe with a slope to the water collector equal to about 5 mm / 1 linear meter.
• Backfilling the pipe with a 25 cm layer of gravel, wrapping the sandwich with the geotextile edges left earlier, backfilling.

Such measures allow water to enter the pipe, eliminating the possibility of clogging. Moisture will freely go into the reservoir.

Vertical

This type of waterproofing strip foundation involves the processing of ready-made basement walls with different materials. Work can be carried out both during the construction of the building and after its completion. In addition, vertical insulation from water is primary (when special hydrophobic additives are used in the construction of a structure that increase the resistance of concrete to moisture) or secondary (if the first type of insulation was not performed).

At the place of arrangement, vertical waterproofing can be external and internal. To accomplish the task, plastering, coating compositions, paint and varnish coatings, various sealing impregnations, gluing materials, antiseptics, biocides, etc. are used.

The need for vertical waterproofing:

• When the soil is influenced by moisture from the soil, which is held in the soil by adhesive or capillary forces and stands there constantly, regardless of the levels of underground, filtration water.
• If melt and rainwater fills the pores in the soil and gets deep into the ground, seeping into the depth of the foundation.
• When the surface layer of underground moisture lies close.

Usually, not only the underground part of the foundation is isolated, but also the aboveground one, in order to exclude the influence of water that has risen up through the capillaries.

Which method is the most optimal

Experienced craftsmen, answering the question of whether it is necessary to waterproof the strip foundation, argue that both types are necessary and desirable. Both horizontal and vertical protection are mandatory - only in this case it is possible to guarantee a long service life of the building and the absence of any structural damage.

Features and types of foundation waterproofing

Building waterproofing increases the strength, reliability and quality of internal waterproofing

Waterproofing a building has a number of advantages and features, namely:

• increases the strength, reliability and quality of internal waterproofing;
• has an uncomplicated method of applying waterproofing;
• there is no need to thoroughly dry the structure;
• high resistance to mechanical damage, scratches and abrasions;
• has the function of “tightening” cracks.

As a rule, protective measures for the foundation and walls are carried out with many building materials. The first who began to engage in the production of protective mixtures were bulk penetron. Penetron is produced and produced in several types, each of which is responsible for a specific function. Divide it into:

• plastering;
• healing cracks;
• impregnation of masonry after construction.

The main task of penetron mixtures is reduced to one thing, to create moisture-resistant crystals that will provide reliable protection. A little later, other brands were added to Penetron, such as: Vandex, Kalmatron, Lakhta, etc.