Facade work

Building Façade is a business card of an organization which occupies this building. Façade condition is in the center of attention of a city administration, companies- building owners and building companies.

We work with expensive foreign materials as well as domestic produced stuff. Work fulfillment is accompanied with the application of scaffold, electric self-elevating chairs, towers, method of industrial mountaineering.

Guarantee: all façade works are guaranteed for 12 months and longer, depending on work difficulty and quality of materials.

We fulfill following façade works:

• Plastering and painting
• Ornamental finishing (rubble stone, sledged stone, facing stone, ornamental tile)
• Lagging
• Siding
• Ceramic granite siding
• Doubling plank mounting
• Paving (concrete, asphalt, flag, slab, ornamental stone).

Physics of walls

Nowadays, in connection with the occurrence of not only new materials but entire enclosure SYSTEMS (consisting of heterogeneous materials), proper attention should be given to understanding of the physical processes occurring in external walls. Without it their competent designing and erection are impossible.

External walls as an enclosure are exposed to influence of different factors closely connected to processes, occurring outside a building as well as inside (pic. 1). Some of these factors are as follows:

• atmospheric precipitation;
• water vapor, contained in the air inside the building;
• ground moisture;
• wind;
• solar radiation;
• temperature difference;
• chemically aggressive substances contained in air;
• and other factors.

Atmospheric precipitation

A slanting rain with a wind exerts profound negative influence on external walls of buildings. Because of aforesaid coastal constructions as well as isolated tower buildings suffer most.

Rain water can get inside of a wall through porous structure of a surface, an aperture, a crack, a chap and leaky seams. The top parts of walls and corners are exposed to the strongest influence of a rain.

Defective gutters can be also the reason wall wetting. Vertical seams of drainpipes should be turned aside a wall to prevent ingress of water onto wall. The distance between a wall and gutters should be not less than 30 mm.

Incorrectly mounted window esconsons can lead to ingress of rain water inside the wall. External edges of window esconsons should be at a distance of 30 mm from the wall. Moreover they should have a sufficient gradient equal to not less 300.

Fire ladders, flagstaffs, lamps, boards, handrail of balconies, etc. are should be mounted thus not to direct rain water on the wall.

Superficial waters on the ground, snowdrifts and sparks of rain water influence the foundation pit and the bottom of a facade. To reduce this negative influence, it is necessary to provide for an inclination of the ground bordered on the wall.

Water vapor

Water vapor is constantly generated inside a building as a result of human activity (cooking, washing, bathing, floor washing, etc.). High level of humidity is observed in recently constructed or repaired buildings. New constructions can sometimes possess extremely high moisture content because of so-called constructive humidity. The higher temperature and more effective ventilation, the faster process of construction drying.

Water vapor, contained in air inside a building, during diffusion and convection diffusion penetrates into a wall and, being cooled down the temperature of dew, condenses. The more difference between temperatures inside and outside, the more amount of condensed vapor. Therefore during winter time moisture rather intensively collects in the wall. Thus it is necessary to understand, that the moisture of internal air can penetrate the wall together with air streams through cracks, splits, unretentive joints and seams.

To keep wall heat-insulating capacities and structural durability it is necessary to let whole moisture collecting in the wall in winter and summer, out of the house.

The most reliable protection from water vapor is necessary in buildings with a high level of humidity: pools, computer rooms, etc. It is essential to pay special attention to vapor protection in regions with extremely cold climate (even with normal humidity inside premises). Negative consequences of this process can be prevented - using various constructive methods (first of all, installation of ventilated gaps), or using vapor sealing materials in wall construction (inside).

Ground moisture

In case of absence of a waterproofing earth and sedimentary waters in the base of a building can rise under influence of capillary forces in the basement. If an insulation between the basement and wall construction is improper, moisture can get into the wall construction. Picture 1 presents some constructive decisions on prevention of moisture penetration from ground into the basement.

Wind

Wind meets on its way with an obstacle in the form of building and goes round it. As a result regions of positive and negative pressure spring up (pic.2). The higher building the stronger wind force. The wind force is obligatory to be taken into account during designing of

Solar radiation

Various materials possess different solar radiation sensitivity. So, for example, the sunlight practically does not influence ceramic tile as well as materials of metals without polymeric coating. On the other hand, paint coating undergoes severe damage in the form of paint cracks on a façade. Some materials do not change their physical properties, but lose visual appeal, fade (paints and some polymeric coatings).

Therefore, choosing a facing material for application in southern regions, it is necessary to make sure, that it possesses sufficient light resistance.

Temperature differences

As an enclosure, external walls function under rather severe conditions, and are exposed to temperature differences. Usually, internal wall surface has the temperature which approximates to the premise temperature. At the same time the temperature of external wall surface varies greatly- from negative (at winter night) to positive- 1000C (sunny summer day). Temperature of external wall can differ because the solar irradiance falls unequally on its surface.

But, as is well known, all materials to some extent undergo a thermal expansion and compression. Therefore in order to prevent deformations and destruction it is very important, that materials used in one construction, have similar temperature expansion coefficients. Otherwise, to use such materials one must apply technical methods.

Frequent sometimes daily temperature fall from plus to a minus can represents a danger to some materials. It occurs, as a rule, in regions with soft and damp winter. To a line of materials daily temperature drops from plus to a minus can serious danger often, sometimes. It, as a rule, occurs in areas to soft and damp winter. Therefore at similar climatic zones it is necessary to pay special attention to such important characteristic of materials, as water absorption.

At positive temperatures the moisture penetrates into wall and accumulates in pores of a material with high water absorption. At negative temperatures the moisture freezes and, expands, deforming the structure of a material, which results in progressive destruction of a material and cracks formation.

Chemically aggressive substances contained in air

As a rule, in big cities or nearby large enterprises there is a high concentration of chemically aggressive substances (for example, hydrogen sulphide and carbonic gas) in atmosphere. That’s why all enclosure parts must be made of materials with resistance to chemical substances contained in air of the region.