One of the most important factors water regime soil is the process of moisture evaporation. Evaporation of water from the soil occurs at any temperature, increasing with increasing temperature and dryness of the air. Evaporation of water from the soil occurs mainly from its surface, however, in soils with moisture content less than the maximum hygroscopicity, evaporation also occurs inside the soil and ground horizons. The rate of intrasoil water evaporation is significantly lower than from the soil surface. Deep fissuring of soils contributes to increased intrasoil evaporation.
Uneven terrain and soil surface also contribute to an increase in moisture consumption for evaporation. The removal of vaporous water by wind increases the rate of evaporation. The rate of evaporation is always greater, the higher the soil moisture. Therefore, in steppe, semi-desert and desert conditions, if high soil moisture is maintained (through irrigation or from groundwater), the actual evaporation reaches high values:

Why are water-repellent impregnations needed, what laws of physics are Durable Water Repellent based on, what modern DWRs are, and how to choose the right impregnation to protect clothing and equipment from moisture

Owners of modern travel clothing or shoes are often faced with manufacturers’ recommendations to periodically treat their products with DWR water-repellent impregnation. This is not objectionable when it comes, for example, to fleece, but why impregnate membrane clothing? After all, the presence of a membrane already implies that the product will reliably protect from rain or sleet.

We wrote about how the membrane itself works in an article about. But the effectiveness of the membrane depends on many factors, not least the DWR.

Even the most expensive membrane will disappoint its owner if an additional water-repellent coating does not protect it from external moisture.

Why do you need water-repellent impregnation?

Strictly speaking, water-repellent impregnation is not needed by the membrane, but front side membrane sandwich. It is the outer layer of clothing or shoes that is first exposed to moisture. What happens when the outer layer gets wet?

Water absorbed by the fibers fills all the air gaps in the fabric and creates obstacles for the free release of evaporation. The breathability of the membrane sharply decreases - the fumes have nowhere to go and the person begins to sweat.

As a result of replacing air with water, the overall thermal conductivity of the clothing layer increases - it becomes colder in it.

External fabric soaked in water becomes heavier.

In order to get rid of these problems, DWR impregnation is used.

How does DWR water repellent finish work?

Durable Water Repellent (DWR) - long-term protection against moisture. To understand the principle of impregnation, it is necessary to remember some physical properties liquids, namely surface tension effect And capillary phenomena, which are also called wick effect.

About the important features of water

Surface tension forces occur because water molecules attract each other. The mutual attraction of molecules causes water to form droplets. Wet condensation on a cooled surface, small water beads or rain drumming on an umbrella - all these are water drops of various sizes. The forces of mutual attraction between molecules are small, and a large drop can be easily destroyed. However, the laws of physics are more difficult to break: a large drop will break into hundreds of small ones, but the principle of their formation will remain the same.

No matter how small the drop, the “sieve” of the climate membrane cannot let it through—even the tiniest drops are too large to penetrate the membrane pores. The larger the volume of water a drop absorbs, the larger the area on the surface of the material is freed from the water film. This means that the area through which evaporation is removed from the body increases. We can say that a “well-fed” and clearly defined drop is the key to successful operation of the membrane.

If the attraction between water molecules and molecules of a solid body is much weaker than the attraction of water molecules to each other, then the drop lies on the surface of the solid body and does not wet it

But can something destroy a drop, smear it into a shapeless film on the surface of the material? Unfortunately yes. The fact is that water molecules are attracted not only to each other. An attraction also occurs between a water molecule and a molecule of any other substance with which the water comes into contact. In some cases, it is so strong that water molecules are literally drawn to molecules of another material, and if this attraction is comparable to the forces of surface tension, the drop stretches and spreads over the material. In such cases, it is usually said that the material is well wetted.

But if the attraction between the molecules of the solid and the water molecules is weak, then wetting will not occur.

If the attraction between water molecules and molecules of a solid body is stronger than the attraction of water molecules to each other, then the drop spreads over the surface of the solid body and is absorbed into its pores - the surface of the solid body is wetted

Most textile materials are woven from threads, and the threads are spun from fibers. There are many air cavities-capillaries in their weaves, and if the material is well wetted, it draws water into all these cavities. This retracting effect is called wick or capillary. It is clear that as long as the material is saturated with water, there can be no talk of any transport of steam through it.

We know how water behaves on a surface treated with grease - it rolls into bead-like drops, does not spread and is easily shaken off. Fat does not attract water. And we remember what happens to a T-shirt when we get caught in the rain or sweat - water molecules are attracted to the molecules of the material, and the liquid is distributed through the finest capillaries throughout the fabric, wetting its fibers.

How to avoid capillary effect? How to weaken the attraction between water molecules and the molecules of the substance that make up the fabric fibers? How to prevent wetting and keep a drop of water “well-fed”, self-sufficient and independent?

This is exactly the problem that DWR solves.

Substitution trick

The laws of physics cannot be changed, but what prevents you from using them to your advantage? The wettability of various materials depends on many factors, primarily on the properties and structure of the fiber, surface roughness, its shape and size. Artificial fibers, such as polyester, generally have low wettability, while natural fibers, such as cotton or wool, are much better wetted. If the material used in the outer layer of clothing wets too well, then perhaps it is worth replacing it with another that is less water-friendly?

Such a solution would be ideal, but, unfortunately, it is difficult to implement. The fact is that the material for the product is selected based on a combination of several parameters, and the wettability characteristic is only one of them. But if you can’t replace the material, then maybe you can change its properties? For example, apply the thinnest film of a non-wettable substance to a wetted material and thereby “deceive” the water?

This is exactly how DWR sealing works. A substance that practically does not attract water molecules is applied to the facial fabric and covers its threads. Water stops being absorbed into the material and collects in drops on its surface. The fabric becomes hydrophobic, that is, it does not wet itself and at the same time allows steam to pass through it.

Substances that reduce wettability

Fatliquoring and waxing - traditional ways imparting hydrophobic properties to the material. Since ancient times, fat and wax have been used to protect shoes from getting wet; they are a classic water-repellent impregnation. After applying wax, an additional layer of a substance is formed between the leather of the boots and external moisture, the molecules of which do not attract or very weakly attract water molecules. As a result of this treatment, the boots will be protected from getting wet for some time.

But neither fat nor wax are suitable for processing high-tech membrane materials. A relatively thick film of these substances will create an obstacle not only to atmospheric moisture, but also to steam, which the membrane should remove to the outside.

Modern chemical water-repellent impregnations are solutions or emulsions that, when applied to fabric or other material, impregnate its fibers, after which the solvent evaporates, and a thin hydrophobic layer of a water-repellent substance remains on the surface of the fabric. Water falling on this protective layer does not penetrate the fabric, rolls into drops, flows off and is easily shaken off.

Types of modern water-repellent impregnations

It is necessary to distinguish between primary factory water-repellent treatment, which is carried out by the manufacturer, and secondary, restorative treatment, which is usually carried out by the owner of the product after washing or certain period operation.

Water-repellent according to their purpose DWR impregnation can be divided into several groups:

impregnations for waterproof breathable fabrics with a membrane;

impregnations for waterproof breathable fabrics without membrane;

impregnations for products with insulation;

impregnation for fabrics where vapor permeability is not important;

impregnation for shoes.

Impregnations for fabrics with membranes are specialized. They are designed in such a way as to ensure the hydrophobicity of the facial tissue and at the same time not interfere with the operation of the membrane.

Impregnations for breathable fabrics without membrane should not interfere with the transport of vapors from the inside.

Impregnations for products where vapor permeability is not important, Suitable for most non-clothing items such as tents or backpacks.

Shoe treatment products can be both universal and intended for specific types materials such as leather or textiles.

Therefore, when choosing an impregnation, you should always strictly adhere to the purpose of this DWR and the instructions for its use.

Long-term exposure to moisture and ultraviolet rays, temperature changes, friction, dirt and washing gradually remove the water-repellent substance from the surface and from the pores of the treated fabric, so it is recommended to update the impregnation from time to time in order to restore the protective functions of clothing and equipment.

You should pay special attention to the area of ​​the shoulders that is located under the straps of the backpack - the water-repellent impregnation wears off there the fastest.

Classification of water-repellent impregnations by degree of protection

Water-repellent impregnations are divided not only by purpose, but also by their resistance to washing off. This characteristic is reflected in the abbreviation (WR, DWR or SDWR) and indicates the number of “washes” after which the water-repellent coating remains 80% effective. In this case, efficiency refers to the area of ​​fabric that has retained the ability to repel water.

The abbreviations used refer primarily to factory application technologies water-repellent impregnations. The type of factory processing can be found out either from the label or from the description of the product or material on the manufacturer’s website.

WR(Water Repellent) - 5/80

The weakest stability. On average, such impregnation loses 20% of its effectiveness after just 5 washes.

DWR(Durable Water Repellent) - 10/80-20/80

Normal stability. Most membrane storm boots have just such a coating applied. Retains 80% effectiveness after 10-20 washes.

SDWR(Super Durable Water Repellent) - 50/80-100/80

High stability. Characteristic for impregnations used in membrane materials and top-class products. Retains 80% effectiveness after 50-100 washes.

We put the word “wash” in quotation marks for a reason. Unfortunately, manufacturers prefer not to mention the fact that washing, in their understanding, is simply rinsing the product in warm water in a gentle mode and without any detergents. As soon as the owner of the product begins to use detergents, the picture is changing.

When washing with special shampoos intended for the care of membrane fabrics, the resistance of impregnations drops by about 5 times. That is, the WR impregnation will have to be restored after the first wash, and DWR - after about the third.

In case of using conventional washing powder the situation is even worse - most water-repellent impregnations will not withstand even one such wash.

Composition of impregnations

Any impregnation consists of two main components - the active substance and the solvent. Modern DWRs can be hydrocarbon solvent or water based.

Hydrocarbon DWR contain fluorocarbon resins, where active substance most often it is polytetrafluoroethylene (fluoroplastic, Teflon). Polytetrafluoroethylene molecules are approximately four times “weaker” than water molecules. In terms of attractiveness, polytetrafluoroethylene is inferior to many substances, so the surface coated with it feels slippery and even greasy to the touch.

However, such impregnations are considered not only durable, but also harmful. They have a strong chemical solvent smell, should only be applied to dry items, and should be processed on outdoors. However, the greatest environmental problems arise at the production stage, when the use harmful substances carried out on an industrial scale. It is not without reason that in recent years, discussions about negative impact perfluorinated compounds on the environment. There was a request to find solutions that minimize the harmful effects of DWR on humans and nature.

Water-based impregnations They are considered more environmentally friendly, they do not contain toxic solvents and do not have such a strong odor. They can be applied to both dry and wet items. These DWRs contain silicone, which does not attract water molecules much more strongly than polytetrafluoroethylene.

Depending on the application method, DWRs are available as liquids in small containers or as sprays. Liquid DWR is used either immediately after washing - the product is immersed in water with a solution for a while - or applied with a foam sponge, squeezing the solution out of the tube. Sprays are convenient to use while traveling.

The basic rule for processing any impregnation is that the item should not be dirty.

Most well-known manufacturers modern water-repellent impregnations on Russian market are Granger`s, Nikwax, Storm Waterproofing, Woly Sport, Holmenkol, Toko, Salamander, Kongur, Collonil.

Summary

Durable Water Repellent (DWR) is a treatment outside clothing, shoes or equipment to give them hydrophobic properties.

• According to the degree of effectiveness, impregnations are divided into WR (5/80), DWR (10/80-20/80), SDWR (50/80-100/80) - the first number in the ratio indicates the number of washes at which 80% efficiency is maintained impregnation.

DWR impregnations ensure effective operation of the membrane during rain or high humidity conditions.

Friction, prolonged exposure to moisture, ultraviolet rays, pollution and frequent washing destroy the water-repellent coating, so the impregnation should be renewed from time to time.

DWR impregnations vary in their purpose. They are used for both membrane and any other water-repellent, breathable clothing, as well as for insulated clothing and shoes.

• When choosing DWR, you should always adhere to the purpose of this impregnation and strictly follow the instructions for its use.

Typically, during construction
country houses hydrogeological and relief features are not taken into account
built-up area, unsuccessful foundation design solutions are used,
waterproofing materials are selected incorrectly and, as a result, basements and
ground floors cannot be used due to incoming moisture at discretion
owners. Constant dampness and mold penetrate the load-bearing structures over the years
structures and foundation elements. Droplets of water fall into the narrowest, sometimes
invisible cracks, with the onset of cold weather the water freezes and, expanding, leads
to damage. As a result of moisture penetration into the building structure,
begins to gradually collapse. “Properly performed basement waterproofing
will ensure the durability of the entire building, protecting against the penetration of water and moisture, and
will also improve its performance characteristics,” believes Vladimir BUKIN, head of sales department
Group of companies "Kalmatron".

Basements are not only in old houses, but also
in modern cottages they are subject to waterproofing, especially those with
the construction of which did not have drainage or external waterproofing. IN
In most cases, the appearance of water in the basement is associated with water that
are divided into three main categories - soil, groundwater And
high water “Without protection, concrete will deteriorate quite quickly. You can protect it from moisture different ways And
materials. The most advanced technologies are offered by Penetron, Kalmatron,
"Hydrotex" and "Prism" (impregnation for concrete "Monolit-20M"). "Roofing felt, bitumen -
It’s not even yesterday, but the day before yesterday. The most profitable, in our opinion
look, material for waterproofing in Western Siberia— this is the impregnation of the “Monolit-20M” series.
It is easy to apply, has no pungent odor, penetrates deeply (up to 5 cm) into concrete and
reliably waterproofs it. One application from the outside or
the inside of the foundation. Cost of 1 sq. m of waterproofing
is about 20 rubles,” explained Yuri PUZYRNIKOV, Director of Prizma LLC.

Where
is there water coming in?

Before you start waterproofing
basement, you need to figure out where the water is coming from into the basement. "Most
probable places for water to penetrate into the basement may be “cold
seams" if the foundation was made in a monolithic manner with a large temporary
interval, between pours and between poured layers there are soil particles
or debris that prevent adhesion (adhesion) concrete layers. Also
Interblock seams may also be insufficiently protected if the foundation
made of blocks, and places where communications enter the basement. In addition to this, in
concrete contains pores, capillaries and microcracks through which
the possibility of through filtration of water into the basement,” added Vladimir BUKIN. When inspecting the basement
Before waterproofing, you should mark all leakage points and be especially careful
perform waterproofing in them. Having determined the places of leaks,
The problem of choosing a waterproofing material arises.

Basement waterproofing work in
old building structures should be carried out together with the removal of salts
and bioflora from all surfaces. Even if groundwater does not rise to
floor level basement, capillary
waterproofing. When the cause of flooding is high water or groundwater
water, the water level may rise above the basement floor. To combat this
Due to this phenomenon, drainage systems are built on the site. As explained Vladimir BUKIN, "horizontal tubular drainage used in
cottage construction, can be of a perfect and imperfect form - then
there is one that cuts through the aquifer completely and cuts through it only partially.
The drainage is cut-off in shape (it intercepts the flow of groundwater from the top
sides of the building and from the sides) or circular (borders the building on all sides).
Last option more reliable and therefore preferable.”

Water penetration problem is often
remains, despite structural changes to the basements (attempts to raise the floor
15-20 cm, fill the basement completely with soil and other similar solutions). Sun? This
does not lead to the desired result - the basement walls may not dry even in
hot season due to constantly seeping water. The situation is sometimes not
water reduction also saves - creating drainage: the groundwater level can
be higher than the base of the foundation, and then water can flood the drainage
system, and the pumps will not be able to pump out water. Thus, even
creating an expensive drainage system, it is also necessary to carry out work with
using quality waterproofing materials.

Protection of the underground part of the building
provides complex system waterproofing foundations and other underground
parts of buildings and structures, which includes various types of horizontal and
vertical waterproofing, as well as drainage.

Types of waterproofing

Horizontal waterproofing
foundations are usually made from rolled waterproofing materials and
laid on the marks of the bottom of the basement floor, just above the blind area of ​​the house
and in the area where the basement floor adjoins the foundation. Last time
Developers are increasingly using penetrating waterproofing. Fast, inexpensive,
reliably, and, most importantly, allows you to do without weight in the form of concrete screed. Vertical
waterproofing is applied to the external and internal surfaces of the foundation. She
can be coating, pasting, penetrating or screen. "For execution
For coating waterproofing, bitumen-polymer mastics and also (less commonly) cement-polymer compositions are used.

Mastics are liquid polymer-bitumen
cold and hot application compositions intended for waterproofing
construction seams, protection and restoration of waterproofing coatings.
Hot mastics acquire waterproofing properties after cooling, and
cold - after drying. Advantages liquid materials- education
seamless enveloping waterproofing film on any surface and
good grip on it. Regular bitumen should not be used for this purpose - as a result of natural aging, it quickly
will become brittle and crack,” comments Vladimir BUKIN.

It must be remembered that in the event
if coating waterproofing is used, any mastic should be applied as
in at least two layers, and between the layers of mastic a reinforcing material must be laid
gasket, for example, made of fiberglass or fiberglass mesh.

Penetrating waterproofing is applied to
the inner and outer sides of the foundation. Penetrating waterproofing composition
is a mixture of Portland cement, finely ground quartz or
silicate sand and active chemical elements. When applied to damp
surface active ingredients react with cement components
concrete (mortar) and form insoluble crystalline complexes, tightly
filling pores and cracks throughout the entire volume of the material. "Laboratory
research and application practice have shown that the usual penetration depth
crystals, for example KALMATRON - about 15 cm. Strength characteristics of building
materials increase by 18-20%, water resistance (W) increases
by four steps. Crystalline neoplasms, not allowing water to pass through, at the same time
time do not interfere with the movement of air, allowing the concrete to “breathe”. designs,
treated with such waterproofing, resist the effects of most
aggressive environments, preventing corrosion and penetration of unwanted chemicals
into the environment. The material is inert, does not contain solvents and does not emit
fumes. The service life of the material is equal to the life of the concrete itself. Processed
similar material concrete structures: resistant to aggressive environments, have
better strength characteristics, more frost-resistant, no drying required
surface, no surface leveling required
protection during backfilling and placement of metal reinforcement, not dangerous
punctures, tears or separation from the surface are waterproof. Waterproofing
KALMATRON materials not only provide a long service life, but also
significantly reduce the cost of waterproofing work,” explained Vladimir BUKIN. In progress
during basement construction, waterproofing is carried out with outside foundation.
Basements in old buildings are insulated from the inside.

Screen waterproofing is used in
conditions close to extreme, for example, under the pressure influence of soil
water It is made in the form of a clay castle, the role of which can be played by special
bentonite clay panels or special geotextile membranes. At
device adhesive waterproofing roll materials are glued to external
foundation surfaces - by fusing (submelting) with burner flames
or using a special adhesive mastic. If the material fits
by melting, the base should be primed with a primer before laying.

“Also for “treating” old basements
technologies for injecting compositions on mineral minerals may be proposed
base, polyurethane, epoxy and other bases. But when it's destructive
the effect of soil, man-made and surface waters big enough for walls
many of the injection materials mentioned above are ineffective
due to insufficient elasticity, poor adhesion to wet surfaces,
inability to bridge internal kinks, - believes Vladimir BUKIN. — There are also methacrylate gels that are quite effective,
but the cost of such waterproofing is often around 6 thousand rubles / sq. m. They
popular in the West, especially in Holland, where a third of the country's territory
is below sea level and the use of methacrylates is more
preferable in conditions of high moisture pressure compared to others
injection waterproofing compounds, such as polyurethanes and epoxy
resins."

Technology
waterproofing basements

As practice shows, the majority
errors leading to damage to the waterproofing layer are allowed precisely on
preparatory stage. A significant number of buildings in Russia suffer from problems
zero cycle, where lack of attention or unprofessional choice of materials
and technologies lead to the emergence of indoor high humidity, What
poses an immediate threat to both health and the integrity of the structure.
Errors encountered when performing insulation work are especially dangerous because
that the work to eliminate them in compliance with all construction rules costs
not cheap, and all subsequent improvements and alterations do not always provide
obtaining waterproofing of appropriate quality.

With all the variety of waterproofing
materials, almost all of them are used on the water pressure side, outside,
when groundwater puts pressure on the waterproofing layer that protects the walls
foundation. Penetrating waterproofing allows waterproofing
work from inside the premises. “Internal waterproofing of basements is used if
the construction of the facility was carried out without taking into account the impact of ground and surface
water, the external waterproofing of the basement is damaged or completely missing, and its
repairs cannot be carried out due to extremely high excavation costs
external foundation wall or other objectively existing reasons,” noted Vladimir BUKIN.

Penetrating
waterproofing

Penetrating waterproofing was
developed yet? in the 40s of the last century by VANDEX. It is based on the effect
capillary conductivity of concrete. Penetrating materials are classified into two types −
applied with a brush and applied with a spatula or spray gun.

"The principle of action of chemically active
substances are the same. The result of quality work will also be
is the same. But with not very high quality.... For example, when using
With KALMATON you, in addition to penetrating into concrete, get an additional layer
1.5-2 mm from the same. This hard layer is completely fused with
concrete. You can see it by eye: no cracks, no chips, no bubbles - that means it’s grown together
and penetrated. Is it so easy to guarantee the continuity of the coating and
continuity of penetration with the brush method of application? It looks like something
is on the surface (I mean stains of material), but has it penetrated, have the builders prepared it well?
concrete surface and have the pores opened? This is not a fact. Traces of material may
may be, but there may not be a guaranteed continuous carpet. From this conclusion
suggests itself - surface preparation for brush penetrating materials
- this is not just important, but extremely important! At the same time, it is also necessary to keep in mind that
brush materials should be used with extreme caution on old concrete, where
as experts know, there is no free lime, i.e., a medium for germination
crystals. But “spatula” penetrating materials, for example KALMATRON,
They are not afraid of this, since they themselves carry a nutrient medium. At the same time, if
However, you have damaged this layer by 1.5-2 mm, the waterproofing will still work, so
how it “sits” in the very pores of the concrete,”
added Vladimir BUKIN.

General condition for working with penetrating
materials - the temperature of the concrete and the temperature in the room itself should not be
lower than +5 °C. The first stage is preparatory. Chemically active components
must penetrate into the body of the concrete, so the concrete must be cleared of cement
“jelly” (its pores are opened), bioflora, various organic pollution.
It is necessary to remove weak fragments, any cement dust that is in
may further negatively affect the adhesion of the material to the concrete
surfaces. Saturate the concrete generously with water. Chemicals penetrate into the body of concrete through
water, how deep the water will penetrate, to the same depth in the pores of concrete
Crystals will grow that will not allow water to pass through. The second stage is working with seams,
junctions, cracks, cavities and sinks. Please note:
“cold” seams, places where the boundaries of the old and new fill are located in monolithic wall.
Since seams are always the most susceptible to leaking, they receive special attention.
attention when working with penetrating materials. The third stage - waterproofing
concrete surface. The fourth stage is care waterproofing layer,
keeping it moist for three days.

“If work takes place in the open
air, when there is active evaporation of moisture from concrete, it is necessary to organize
covering works. If required by the situation, then protection should also be provided
from capillary ground moisture (even if the groundwater is below
basement), for which horizontal cut-off of capillary moisture is carried out using the
injection (for example KALMATRON-D). With this method it is possible
plug capillaries for effective waterproofing of basements. If all
associated factors are taken into account if settlement of the foundation walls has already occurred and
no further progress is expected, penetrating waterproofing - good chance
solve the problem from inside the room, without digging up the foundation, especially since it is not
limits the time of work to a certain season. You can spend
waterproofing works even in winter. Especially if you know what happened to the old one
you have problems with isolation - don’t wait for spring or autumn, when in emergency mode
it will be necessary to eliminate both the leaks themselves and their consequences,” noted Vladimir BUKIN.

Service life of penetrating waterproofing
is equal to the life of the entire foundation, and there is no need to repair it. At
In this case, the walls remain vapor permeable. “This year we are launching production
dry mixtures based on HYDROCONCRETE SRG-2, SRG-1 and KALIMATRONA-EKONOMA with microfiber. What will add to the finished product?
even more strength, crack resistance and even water resistance. Repair data
compositions will be very relevant at sites where concrete elements have lost their
bearing capacity and are close to normal wear and tear. We use “pilot” already in
some regions, now we will launch production in our city
Novosibirsk,” comments Vladimir
BUKIN.

Trends
market

Russian waterproofing market
materials is characterized by a significant variety of domestic products
and foreign production. “The main part of the market belongs to traditional
bitumen-polymer materials - bitumen and roofing felt, which have the lowest
price, and therefore are used more often than others in construction. Many specialists
note that bitumen will not be replaced soon innovative materials, —
added Vladimir BUKIN. - Market
today offers a huge number of both our Russian and imported
waterproofing materials. If they are not selected correctly, the problem will not be solved.
It will either succeed at all, or you can achieve a short-term effect. Trying
protect the walls of your basement with various waterproofing compounds from the inside
without consulting specialists, you can waste a lot of money and
nerves".

Among the manufacturers of penetrating
waterproofing experts highlight the following companies: Kalmatron, Schomburg (Akvafin),
“Lakhta”, “Xipex”, “Stromix”, “Penetron”, etc. Moreover, the share is precisely
domestic waterproofing exceeds the share of imported ones. At the same time almost
half of the market players produce penetrating waterproofing. By by and large,
here everything is determined by the habit of the developer. Bitumen-polymer materials
occupy a large market share, although the emergence of new technologies still pushes consumers
towards innovation. “If the economic situation is favorable, the market for this
products will grow and grow. There is still a long way to go before saturation. We're so decent
residential and industrial infrastructure was “destroyed” in the 90s, what to repair?
and we will be restoring for a long time,” concluded Vladimir BUKIN.

“It is worth noting that both customers and
clients are becoming more demanding, more informed, and this,
certainly has a very positive effect on the building materials market in
in general. The market for waterproofing materials will expand, it is far from
saturation,” comments Elena
BAGUTO, Development Director, Trading House "Stroyding", official dealer of CJSC "GC "Penetron-Russia" on
territory of the Novosibirsk region.

Every day, the skin of every person is influenced by various negative factors, such as weather conditions, the environment, and the ecological situation in the region of residence. Most negative impact The skin is exposed to ultraviolet rays when exposed to the open sun or during normal tanning. But the effect of air humidity on the skin is also important, since there are many subtleties here.

Humidity and skin

Of course, every person has noticed that on hot days and dry weather, as well as when exposed to dry wind for a long time, one becomes very thirsty. The body at this time requires a large amount of fluid, as it loses water due to external natural factors and needs to replenish these losses.

However, even when drinking large volumes of liquid in the presence of dry air, skin cells do not have enough moisture to function normally, since it evaporates in large quantities through the skin.

Air humidity is a certain indicator of the amount of water contained in it. This indicator is of particular importance for general condition a person and his skin, and also affects the degree of comfort of being indoors or outdoors.

For example, in summer time, on the hottest days, most people find it very uncomfortable to be outside because it is difficult to breathe. This is explained by the fact that when heated, the air is saturated with moisture (its evaporation from the surface of reservoirs and soil), and the higher the air temperature, the greater the volume of water it can absorb. As a result, on hot days, especially if it has rained before, people experience serious discomfort and breathing problems. Of course, this condition also affects the skin, since the heat causes increased sweating, which can lead to serious fluid loss.

Almost the same thing happens in winter time when on the street very coldy. During this period, air humidity usually decreases, since due to the low temperature water does not evaporate, but at the same time the air is also ready to accept moisture and absorb it. As a result, in the cold it is very difficult to breathe due to the dry air. With breathing, a lot of steam comes out, the molecules of which are immediately absorbed into the air. As a result, the body loses large volumes of water. The air takes water away from the skin of the face, as well as from other open areas of the body. That is why, after a long stay in the cold, as well as in the heat, the skin becomes dry and dehydrated.

As a rule, if the air temperature is high, but the air humidity is low, people tolerate it much more easily and have less impact on the condition of the skin. At low temperatures accompanied by high levels of air humidity, rapid hypothermia can occur.

What are the dangers of violating the humidity level?

The most comfortable indicators of air humidity for a person’s condition, his health and maintaining the correct water balance in the body and skin cells is a value from 30% to 60%. If the indicators deviate in any direction, this can lead to various negative consequences.

At low air humidity, due to strong evaporation of moisture, the skin very quickly dries out, becomes dehydrated, and begins to peel and crack. As a result, damage to the skin appears, which is not always noticeable to the eye, but, nevertheless, allows free access to the body for a variety of pathogenic microorganisms that can provoke the formation of an inflammatory process and acne, as well as infection with serious diseases.

In addition, when the humidity is too high in the hot season, the body sweats intensely, trying to cool the skin and protect it from overheating, not only losing water, but also forming a sticky film on the surface of the skin, to which dust and other contaminants stick. The result can be not only dehydration of the skin, but also a large number of acne caused by clogged pores and sebaceous ducts.

If the air humidity is high, the body begins to lose heat simultaneously with intense sweating, resulting in a serious risk of overheating. In this case, not only the human skin suffers, but the entire body. With prolonged stay in rooms with high air humidity, a person may experience a general decrease in immunity, which results in not only skin diseases, but also various diseases internal organs, and exacerbation of existing diseases occurs.

Of course, it is impossible to say unequivocally that when the level of air humidity increases or decreases, a person will definitely develop skin problems, since each organism is individual and its reaction to certain changes environment, it is simply impossible to predict. The reaction of different people's skin to changes in the environment will be different, and if a certain level of air humidity has a positive effect on the skin of one person, then it may be negative for the skin of another person.

For example, with dry skin, a high level of air humidity will be useful, since the water in the air will become an additional source of hydration of the epidermis. A low level of humidity with dry skin will provoke the appearance of peeling and dehydration. In addition, humidity helps smooth out wrinkles. However, if you have oily skin, high humidity levels can be a factor in causing acne. Therefore, quite often the condition of the skin depends on the air humidity in the apartment or other room.

In most cases, in winter, the air in apartments and houses has a low level of humidity, which is facilitated by the work of various heating devices. As a result, the skin becomes drier, thinner, and may show signs of aging. Therefore in winter period the skin needs additional care, hydration and nutrition. It is also recommended to humidify the air in the apartment, using special air humidifiers or simply placing containers with clean water, the evaporation of which will provide additional humidity.

As a rule, in order to avoid unwanted consequences and complications, cosmetologists recommend adjusting to a certain level of air humidity, providing the skin with the necessary conditions. At low humidity levels, the skin must be treated with creams and other products for deep intensive hydration and nutrition. Such products have a fairly dense structure, and their use helps prevent dehydration. However, when high level Humidity should also not be forgotten about hydration, especially in the summer. But creams with a dense structure are not suitable here. In summer, it is best to use moisturizing gels that quickly penetrate the skin and do not create unnecessary heaviness.

Video about dry air in apartments

Evaporation of moisture from water surfaces in indoor water parks.

CEO

"Stroyinzhenerservice"

Chief Specialist

"Stroyinzhenerservice"

Professor of the VITU department

doc. tech. sciences

In indoor water parks, various pools and water attractions are the main sources of significant moisture inputs, which must be taken into account when designing their ventilation and air conditioning systems. Insufficient accounting of moisture inputs from these sources can lead to the constant occurrence of moisture condensation from the air during the operation of indoor water parks. internal surfaces various building structures and non-compliance with the permissible temperature and humidity conditions of the air environment in the area where swimmers stay. Our experience in designing ventilation and air conditioning systems for indoor water parks has shown that a thorough analysis is required to assess their moisture inputs:

– technological modes use of swimming pools and water attractions;

In this regard, it should be noted that the greatest difficulties arose with the establishment (reasonable choice) of calculated dependencies for determining moisture inputs from water surfaces.

Currently, there are many formulas recommended for estimating moisture evaporation, which are based on the results of laboratory experiments. Doubts have arisen that laboratory experiments take into account the full extent of the conditions under which moisture evaporates from the water surfaces of pools and attractions in indoor water parks. Therefore, it was decided to analyze the calculated dependencies to determine the intensity of moisture evaporation from water surfaces, recommended by various regulatory documents existing in domestic and foreign practice. When performing analysis Special attention attention was paid to the conditions for obtaining and possible areas of application of the recommended calculated dependencies for assessing evaporation from water surfaces.

In domestic practice To calculate the amount of moisture evaporating from an open water surface, the dependence proposed by the drying laboratory of the All-Union Thermal Engineering Institute (Moscow), which is based on the results of extensive experiments conducted under the following conditions, has been widely used:

– air temperature – t=40÷225 0С;

– air speed – υ=1÷7.5 m/s.

In the experiments, evaporation conditions close to the adiabatic process were provided. The dependence developed in this case was included in the “Instructions for the design of heating and ventilation” (SN 7-57), and then in the “Designer’s Handbook. Ventilation and air conditioning” book. 1, ed. 1992 (SPV) as follows:

G=7.4(аt+0.017∙υ)∙(Pн-Рв)∙∙F, (1)

where G is the amount of evaporating moisture from an open water surface with area F (m2), kg/h;

υ – relative speed of air movement over the water surface, m/s. For swimming pool halls, according to SNiP 2.08.02-89*, no more than 0.2 m/s can be recommended;

аt – coefficient depending on the water temperature in the pool (0.022÷0.028 at twater=28-40 0С);

Pv – partial pressure of water vapor in the air of the working area of ​​the room, kPa;

Pн – pressure of saturated water vapor in air at a temperature equal to the temperature of water, kPa;

As noted by Prof. in the book “Ventilation, Humidification and Heating in Textile Factories” (ed. 1953), formula (1) is a modified Dalton formula, which has the following form:

G= , (2)

where C is the evaporation coefficient (0.86 – with strong air movement; 0.71 – with moderate air movement; 0.55 – with calm air).

This dependence was obtained by Dalton as a result of his numerous experiments on the evaporation of water, which was heated in round bowls ø8.25 and ø15.24 cm on braziers to different temperatures. At the same time, in the experiments, the speed of air movement above the evaporation surface varied arbitrarily. Therefore, Dalton’s formula does not indicate quantitative characteristics of the speed of air movement above the evaporation surface. In the book “Ventilation” (ed. 1959) prof. An estimate of the possible speeds of air movement in Dalton's experiments is given:

– with strong air movement, the air speed could be 1.57 m/s;

– with moderate air movement - 1.13 m/s;

– in calm air conditions - 0.58 m/s.

Based on these data, the value of the evaporation coefficient C = 0.4 was established at an air velocity above the evaporation surface of 0.2 m/s.

In foreign practice To calculate the evaporated moisture from the water surface of swimming pools, the formulas given in the Dantherm Design Guide are used, which make it possible to take into account the influence of the occupancy of the pool by swimmers and their activity on the evaporation of moisture. The Guide notes that in Germany the formula of the VDI 2086 standard developed by the Society of German Engineers is used to calculate the evaporation of water from the water surface of indoor swimming pools:

G=ε∙F ∙(Pn-Rv)∙10-3 , (3)

where ε is the empirical coefficient of water evaporation from the water surface of the pool, g/m2∙h∙mbar, depending on the mobility of the water surface, the number of swimmers and their activity.

e=35 – for pools with slides and significant wave formation;

e=28 – with average mobility of the water surface for public swimming pools and normal activity of swimmers (pools for recreation and entertainment);

e=13 – with a low-moving water surface for small swimming pools with a limited number of swimmers;

e=5.0 – for still water in swimming pools;

e=0.5 – closed water surface in swimming pools.

It should be noted that formula (3) is also a modification of Dalton’s formula, and its empirical coefficient e reflects the influence on the process of moisture evaporation of both the speed of movement of the water surface and the speed of air movement due to the relative speed of movement of these media.

In the UK, to calculate the amount of moisture evaporating from the water surface of swimming pools, as noted in the Dantherm Design Guide, the Byazin-Krumme formulas are more often used, which are established on the basis of field measurements of the intensity of moisture evaporation carried out in existing swimming pools. For the daytime period (the period of use of the pool), the Byazin-Krumme formula is recommended in the following form:

G= ∙F , (4)

where A is the pool occupancy factor for swimmers, depending on the number of swimmers n (people) and the area of ​​the pool F (m2);

DP is the difference between the water vapor pressure of saturated air at the water temperature in the pool and the partial pressure of water vapor in the pool air, mbar.

For the night period (during the period of inactivity of the pool), the recommended Byazin-Krumme formula is:

G= [-0.059+0.0105∙]∙F (5)

We carried out calculations of the intensity of moisture evaporation from the water surface of swimming pools during the period of their use (in daytime) according to formulas (1÷4). At the same time, three types of pools and water attractions were considered depending on the temperature of the water used:

type 1 – general pools of water attractions, twater=30 0С;

type 2 – children's pools, twater=35 0С;

type 3 – Jacuzzi pools, twater=40 0С.

The following were taken as initial data in calculating the rate of moisture evaporation when using swimming pools:

Рн – pressure of saturated water vapor in the air at the water temperature in the pools (for pools of type 1 - 37.8 mbar; type 2 - 42.4 mbar; type 3 - 73.7 mbar);

Рв – partial water vapor at acceptable air parameters for all types of pools. In the warm period of the year Рв=25.4 mbar (tadd=30 0С and jadd=60%), in cold period year Рв=20.1 mbar (tadd=29 0С and jadd=50%).

Thus, the calculated values ​​DP=(Рн-Рв) for various types pools are for pools of type 1 from 12 to 18 mbar; 2 types - from 18 to 23 mbar; 3 types - from 48 to 54 mbar.

When calculating the intensity of moisture evaporation, the following were taken:

– in formula (1) the average value of the coefficient аt=0.025 at air speeds υ=0.2; 0.9; 1.5 m/s and Pbar=101.3 kPa;

– in formula (2) air speed υ=0.2; 0.9; 1.5 m/s, and the value of Pbar = 760 mm. rt. Art.;

– in formula (3) the values ​​of the coefficient e=35; 28 and 19;

– in formula (4) the values ​​of pool occupancy by swimmers: A=0.5; 1.0.

The results of calculations of the intensity of moisture evaporation from water surfaces using formulas (1÷4) are presented in the graphs in Fig. 1, a comparison of which allows us to note the following.

The results of calculations of moisture evaporation from the water surface using the formulas of the VDI standard (at e=35; 28 and 19) and SPV (at air speed over the water surface υ=1.5; 0.9 and 0.2 m/s) coincide with the results calculations using Dalton's formula (at air speeds υ=1.5, 0.9 and 0.2 m/s). This indicates that these formulas were obtained based on the results of laboratory experiments similar to Dalton’s experiments. These laboratory experiments are characterized by following conditions:

– a calm, smooth (without wave formation) water surface of evaporation, above which, when air moves, there is always an indestructible boundary layer of air with the pressure of saturated water vapor at the temperature of the water surface;

– the temperature of the water surface is several degrees lower than the temperature of the bulk of the water, i.e., the process of heat and mass transfer between the water surface and the air moving above it “tends” to an adiabatic process.

The area of ​​results for calculating the intensity of moisture evaporation from the water surface using the Byazin-Krumme formula (at values ​​of the swimming pool occupancy factor A from 0.5 to 1.0) “lies” below the area of ​​results for the intensity of moisture evaporation established using the Dalton, SPV and VDI standard formulas . This indicates the presence of fundamental differences in the process of heat and mass transfer between the water surface and air environment operating pools from the process of heat and mass transfer when conducting experiments in laboratory conditions. These fundamental differences in the process of heat and mass transfer in operating swimming pools and water attractions include:

– constant destruction of the water surface (formation of waves, splashes and drops), the intensity of which depends on the occupancy of the pools by swimmers and their activity;

– constant destruction of the boundary layer of air above the water surface with the pressure of saturated water vapor at a temperature equal to the temperature of the water in the pool, which is established as a result of its mixing by swimmers. Therefore, the process of heat and mass transfer between the water surface and the air moving above it in this case does not “tend” to an adiabatic process, but is essentially some kind of polytropic process, “directed” at the temperature of the water established throughout its entire mass in the pool.

The results of calculations of the intensity of moisture evaporation, obtained using the formulas of Dalton, SPV and the VDI standard at an air speed of υ = 0.2 m/s, intersect the range of results of calculations of the intensity of moisture evaporation, obtained using the Byazin-Krumme formula with values ​​of the pool occupancy coefficient for swimmers A from 0.5 to 1.0. The nature of the intersection of these results emphasizes the above-mentioned fundamental difference between the conditions of moisture evaporation during laboratory experiments and the conditions of moisture evaporation in operating pools.

The above allows us to conclude that the most objective data on the intensity of moisture evaporation from the water surfaces of swimming pools and water park attractions during the period of their use can be obtained by assessing them using the Byazin-Krumme formula (formula 4). In this case, it is necessary to take the values ​​of pool occupancy by swimmers A, based on existing standards their use. In accordance with the Dantherm Design Guide, the swimming pool occupancy values ​​A are determined by the formula:

where 6.0 is the standard value of the pool area per bather (m2/person) with occupancy factor A=1.

For most public swimming pools, it is recommended to take the value of the pool occupancy factor A = 0.5 as the calculated value.

We calculated the intensity of moisture evaporation from the water surface of the pools during the period of inactivity (at night) using formulas (1÷3 and 5). In this case, the initial data were taken to be the same as for the period of use of the pools. In this case, when calculating the intensity of moisture evaporation, the following were taken:

– in formula (1) air speed υ=0;

– in formula (2) at air speed υ=0 evaporation coefficient C=0.3;

– in formula (3) the value of the evaporation coefficient is e=5.0.

The results of calculations of the intensity of moisture evaporation from the water surface using formulas (1÷3 and 5) are presented in the graphs in Fig. 2, a comparison of which allows us to note the following.

The results of calculating the intensity of moisture evaporation from the water surface using the Dalton and SPV formulas significantly exceed the results of calculating the intensity of moisture evaporation from the water surfaces of pools using the formulas of the VDI standard and Byazin-Krumme. This circumstance can be explained by the fact that the formulas of the VDI and Byazin-Krumme standard more strictly take into account the real temperature and humidity conditions of interaction of air with the surface of the water during the period of inactivity of the pools, while the Dalton and SPV formulas, based on the results of laboratory experiments, do not reflect these conditions. Therefore, to calculate the intensity of moisture evaporation from the water surfaces of pools during periods of inactivity, preference should be given to the latest formulas and, above all, the Byazin-Krumme formula.

1. For indoor water parks, the dependencies of the Designer's Handbook cannot be recommended. Ventilation and Air Conditioning" to determine the intensity of moisture evaporation from water surfaces, based on the results of experiments that do not take into account the operating conditions of existing swimming pools and water attractions.

2. When designing ventilation and air conditioning systems for indoor water parks, to determine moisture inputs from the water surfaces of pools and water attractions (during their use and inactivity), it is advisable to use the Byazin-Krumme formulas, as they most fully reflect the processes of moisture evaporation in operating pools.