SP plaster facades. Ventilated facade: installation technology. Requirements for load-bearing frame elements

Ventilated facades appeared in our country relatively recently, but have already gained popularity. It's all about a number of advantages, such as aesthetic appeal, noise, hydro and thermal insulation, as well as the possibility of installation at any time of the year and in any weather. However, in the field of installation and design of facade structures, a number of controversial issues have not yet been resolved.

Normative base

New construction technologies have been used in Russia for more than twenty years, but the regulatory framework governing their use began to appear only a few years ago. Rosary legislative framework, regulating the standards of use and, there is no today. But we also cannot talk about the complete absence of any SNiP in this area.

Today, designers are guided by documents such as SNiP on thermal protection of buildings and on the design of thermal protection. Standards 02/23/2003 partially address the task of energy saving in buildings, reducing heat and energy losses, efficient engineering equipment buildings. SNiP for thermal protection corresponds building regulations developed countries.

Also, the requirements for the arrangement of ventilated facades include fire safety, regulated by SNiP 21-01-97. According to the regulations everything hanging systems must undergo mandatory fire tests, based on the results of which a permit for installation is issued.

Fire safety hanging structures depends on a number of factors, including the materials used and compliance with installation rules. Often, in order to save money, developers choose cheap structural elements, which inevitably affects the quality and further safe operation.

To increase the level of fire safety of ventilated facades, it is necessary to adhere to the following recommendations:

1. When installing, you should use only those composite panels that have passed fire tests as part of ventilated façade systems and that have been assigned the appropriate fire safety class.
2. Ventilated facades with composite panels can only be used if all requirements for the design are strictly observed, with which the system has successfully passed fire tests. Changing any design decisions without agreement with the relevant authorities is prohibited.
3. It is impossible to use curtain facades with composite panels, relying only on fire safety certificates issued by accredited certification bodies. The time and power of thermal exposure during these tests are not comparable with the parameters of fire tests, with the help of which the real fire hazard of suspended structures is established.

Features of installation of ventilated facades

All these important regulations regarding the use curtain facades, are advisory in nature. Therefore, developers still have the opportunity to save on materials, which often harms not only quality, but also safety. The solution in this case may be the use of ready-made hanging structures with proven compatibility of components. Similar systems are produced by both Russian and foreign companies.

Typically, the components of ready-to-assemble curtain walls are accompanied by technical approvals and all necessary certificates. Unfortunately, on domestic market only 60% were certified. But from the quality hanging panels and frame elements depend not only on the efficiency and reliability of the ventilated facade, but also on its safety.

Requirements for load-bearing frame elements

The substructure of the suspended facade must withstand the weight of the facade itself, wind and weather loads, and have high corrosion resistance and fire resistance. Therefore, it is preferable to use load-bearing elements made of materials such as aluminum, galvanized steel with a protective coating and stainless steel. Cheap analogues significantly reduce the durability and safety of the curtain wall.

To attach the cladding to the structure, it is preferable to use steel fasteners, since aluminum does not have the necessary strength. When attaching the supporting structure to the wall and installing the elements together, it is very important to use special separating elements, since the interaction of metal and aluminum leads to an electrochemical reaction and accelerated corrosion.

The most serious requirements are imposed on anchor fastenings: durability, strength, resistance to corrosion, etc. Saving when choosing anchors can lead to the collapse of the entire system. The diameter and depth of fastening of these elements is selected depending on the wall material.

Air gap

The width of the air channel is also of considerable importance. In accordance with SNiP, it should not be less than four centimeters, as this reduces the speed air flow, can lead to blockage of the ventilation duct and wetness of the thermal insulation. However, it should not exceed ten centimeters.

Thermal insulation

Due to the constant circulation of air in ventilation duct curtain façade there is a danger of rapid flame spread; therefore, the main requirement for insulation is its non-flammability.

Acceptable insulation materials are fiberglass or stone wool.

In addition, it is important that the thermal insulation holds its shape well, is resistant to weathering and is durable.

Want more information on the topic? Check out these articles:

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Regulatory legal framework

Facade systems (FS) are increasingly used in the implementation of modern architectural and design solutions, for thermal protection of buildings, when changing functional purpose(for example, the creation of modern business centers on the basis of production facilities), reconstruction of buildings and structures.

To put a building or structure into operation in accordance with Articles 54 and 55 of the Town Planning Code of the Russian Federation, it is necessary to obtain a conclusion from the State Construction Supervision Authority (GSN) on compliance with the requirements technical regulations And project documentation.

It should be taken into account that according to Article 60 of the Town Planning Code (as amended by Federal Law No. 337-FZ of November 28, 2011), in the event of harm to a person or property... due to destruction or damage to a building or structure... its owner compensates for damage in accordance with civil law and pays compensation in excess of damages:

To the relatives of the victim... in the event of the death of the victim - in the amount of 3 million rubles;

To the victim in the event of serious harm to his health - in the amount of 2 million rubles;

To the victim in the event of moderate harm to his health - in the amount of 1 million rubles.

Despite such a high economic risk and legal liability, the problem technical regulation in relation to facade systems continues to be very acute.

Fires of façade systems, incl. using glazed facades, in buildings with severe consequences:

32-storey building "Transport Tower" in Astana, May 2006;

Office center "Dukat Place III", Moscow, April 2007;

Administrative and residential complex "Atlantis", Vladivostok, July 2007;

30-story building, Shanghai, 2011, 53 dead, more than 100 injured;

40-storey residential building "Olympus" (Grozny, April 2013)

show the imperfection of the relevant requirements of regulatory documents, the problem of using counterfeit products (according to the RSPP and Rostandart for building materials, its share reaches 50%), quality installation work and operation, the need for an individual approach to the design of fire protection systems for such buildings, including the development of special technical specifications(STU - in accordance with the Decree of the Government of the Russian Federation of February 18, 2008 No. 87 “On the composition of sections of project documentation and requirements for their content”), including in terms of requirements for facade systems (FS) and their monitoring systems.

Such monitoring of the FS should be integral part structured monitoring and control system engineering systems buildings and structures (SMIS) in accordance with GOST R 22.1.12-2005.

Taking into account the above and the fact that the use of façade systems that do not comply with regulatory requirements does not ensure compliance with the requirements of Article 52 of the Federal Law No. 123 /1/ for the protection of people and property from the effects of hazardous fire factors and (or) limiting the consequences of their impact, in Article 87 of the Federal Law /1/ amendments were made to Federal Law No. 117 dated July 10, 2012,

namely:

"In buildings and structures of I-III degree of fire resistance, except for low-rise residential buildings (up to three floors inclusive) that meet the requirements of the legislation of the Russian Federation on urban planning, it is not allowed to carry out finishing external surfaces external walls made of materials of flammability groups G2-G4, and facade systems should not spread fire."

A number of additional requirements are included in SP 2.13130.2012 /2/ (information on the need to apply SP 2.13130.2009 is posted on the website of the VNIIPO EMERCOM of Russia),

namely:

clause 5.4.12 “For external walls with stained glass or strip glazing, fire walls of type 1 (REI 150) must separate it. In this case, it is allowed that fire walls do not protrude beyond the outer plane of the wall”;

clause 5.4.18 "...The fire resistance limit of structures of external translucent walls must meet the requirements for external non-load-bearing walls" (according to Table 21 of the appendix to the Federal Law /1/, for fire resistance degree I - E30, for II-IY - E15 ", that is, fully glazed facades must be made of fire-resistant glass. In addition, it is established "for buildings of I-III degrees of fire resistance for external walls that have translucent areas with a non-standardized fire resistance limit (including window openings, strip glazing, etc. .p.), sections of external walls in places of abutment to floors (interfloor belts) should be made blank with a height of at least 1.2 m, and the fire resistance limit of these sections of external walls (including junction and fastening units) should be no less than the required fire resistance limit of the ceiling according to limit states EI".

The general requirements for the design of the FS are established by SP 50.13330 /3/. Fire safety requirements for external insulation systems for facades, incl. and to mounted FS, SNiP 21-01-97* /4/ were previously installed. Requirements for the entire FS and each of its elements must be reflected in the technical certificate issued by the Federal State Institution " Federal Center certification" of Gosstroy.

Particularly difficult is the case when the entire building is covered in a translucent shell. For such an architectural and constructive solution, the fire safety requirements in the Federal Law /1/, SP 2.13130.2009 /2/, SP 4.13130.2013 /5/ are essentially not provided for. In addition, the implementation of the requirements of Part 1 of Article 80 of the Federal Law /1/ and Section 7 of SP 4.13130.2013 /5/ to ensure access for firefighters and delivery of fire extinguishing equipment to any premises remains uncertain.

Article /6/ provides an overview of the regulatory documents of the European Union, the USA, and China in relation to facade systems, including requirements for their testing, quality control of their manufacture and installation, and ensuring safe operation. The main conclusion is the need to develop uniform standards on façade structures, including their classification, basic requirements for components and the structure as a whole, methods of their comprehensive testing, quality control during the construction of buildings.

Application of facade systems

Taking into account the above, we will briefly consider modern facade systems and the features of their application.

Depending on the type of cladding, FS are divided into systems:

With porcelain stoneware cladding; -

Cladding with aluminum-based composite materials (alucobond, reinobond, alpolik, etc.);

Facing in the form of cement-fiber sheets (fiber cement, asbestos cement);

Metal cladding in the form of sidings, cassettes, panels, etc.

At the same time, the share of curtain wall systems by groups of construction (reconstruction) projects is:

New residential buildings – 45%,

Housing reconstruction – 35%.

About 30% of the area of ​​suspended facade systems is covered with fiber-cement and fiber cement boards, approximately the same amount is accounted for by porcelain stoneware (32%).

Composite panels and metal cassettes account for 20% and 13% of the area of ​​insulated facades, respectively.

Features of the fire hazard of FS are discussed in detail in article /7/, including:

Plaster systems for external insulation of facades, where slab polystyrene foam (EPS) and some types of polyurethanes (PPU) are usually used as insulation;

Hinged ventilated facades (VF), where one of the features of fire hazard is the use of insulation, either mineral wool slabs with an outer surface made of fiberglass (“laminated” slabs), or a special vapor-permeable polymer film, as a hydro-wind protection.

Based on the results of fire tests, it is indicated that the use of cladding in non-flammable airborne structures in the form of flat elements made of three-layer products made of aluminum sheet with a middle layer of non-combustible material based on aluminum hydroxide is not dangerous; In addition, other things being equal, the use of three-layer panel cladding with aluminum sheet skins and a polyisocyanurate middle layer is safer compared to three-layer panel cladding with aluminum sheet skins and a modified polyethylene middle layer.

Regarding the use of windproof films (membranes), we note article /8/, which points out the ambiguity of the conclusion about the need for their use (it depends significantly on the structure of the fibers of the insulation, and the weight loss of the insulation, according to the results of weathering experiments, is quite insignificant), and the corresponding decision should be take into account the experience of researching the technological and flammable properties of windproof membranes accumulated by the Center for Fire Research of the TsNIISK named after. V.A. Kucherenko.

In /9/ it is noted that due to insufficient qualifications of installers and for reasons of economy, instead of windproof film, films with great value resistance to vapor permeation, up to polyethylene film. At the same time, windproof films are products based on polymer based, belong to materials of flammability group G2 or G3, which actively contribute to the development of combustion from exposure to open fire.

An example is given of the fire of the Tyvek film during welding work on the 17th floor of a building with installed FS, which led to the spread of the fire to the first floor and to numerous damage to the FS. Indicated on frequent use open fire when carrying out a number of works on a building with an already assembled facade: roofing on the roof, welding work on balconies and loggias, fusing waterproofing on the blind area of ​​the building, etc., so in practice it is very difficult to exclude the possibility of fire of the windproof film.

In /10/, as an alternative, it is recommended to use insulation with a caching layer of flammability group no lower than G1 (for example, mineral wool slabs"ISOVER Ventiterm Plus"). If it is necessary to use protective membranes in the FS, then you should search for other non-flammable (NG) or low-flammable (G1) wind-hydroprotective and vapor-permeable materials.

The RD on industrial safety does not mention, for example, advanced technologies such as structural glazing or planar facades.

Structural glazing is a technology for attaching double-glazed windows to the facade of a building using silicone, where the silicone layer is a load-bearing structural element.

In /11/, Schuco structural glazing systems are considered, when the creation of a homogeneous façade surface occurs through gluing (a U-shaped silicone seal is used for flat designs or sealant) glazing (glasses of various thicknesses are used from the inside and outer sides thickness from 6 to 14 mm) onto a supporting post-transom structure, i.e. without supports visible from the outside. The glazing fields are separated by deep seams, and the built-in opening elements do not violate the plane of the facade.

New fittings ensure the use of large opening sashes weighing up to 250 kg and 300 kg in blind fields with varying positive and negative wind pressure.

/12/ discusses the products of the Pilkington Suncooltm line, which combines effective thermal insulation properties with one of the most low U-values for double-glazed windows and wide possibilities for sun protection. Most of products are available in impact-resistant versions, in particular Pilkington Optilamtm laminated glass, consisting of several layers of glass and a film between them, which are firmly connected to each other. When glass cracks or breaks, the film holds glass shards in place, reducing the risk of injury and maintaining structural integrity. One of the options for using such glass, apparently, could be covering atriums.

From the point of view of the thermal characteristics of facade glazing, /6/ notes that the developed new classes of low-emission coatings make it possible not only to reduce heat loss due to the radiant component, but also in combination modern design spacer frame with filling the space between the glass with inert gas to practically bring the facades’ thermal characteristics to a qualitatively new level.

Planar facades /13/ - the most important functional and architectural and construction element is a steel structure, where steel tubular trusses serve as flat load-bearing structures, vertical racks, rod and cable-stayed pre-stressed trusses, as well as a system of vertically tensioned ropes.

For planar glazing, among other types, it is used strained glass. In Europe, ventilated planar facades are used for glazing business centers, train stations and public buildings. During the renovation phase, planar facades can be combined with classic old buildings. The air gap between the glass and the wall allows you to ventilate rooms by creating a directed convection flow, and also create optimal conditions to remove moisture from the insulation of the main wall.

Glazing systems: clamp-on (consists of supporting parts for supporting the glass, which is fixed from the outside by strips) and “spider” (implemented by point-based support of the glass on a round head, which requires drilling the glass. However, in the event of a fire, the glass can quickly become locked in a metal structure and its rupture in the area of ​​the holes with subsequent collapse.The solution to the problem is possible in the installation of a ball joint in the point mounting of the spider, sufficient dimensions of the seam between the glasses, installation of silicone gaskets in the holes to prevent contact between glass and metal.

With regard to ventilated FS (SVF), we can note /14/, where for installation the design of a new original sliding bracket made of alloy is proposed, which allows the use of insulation with a thickness of up to 250 mm and on walls with any possible deviations from the vertical. In this case, each fastening element (clasp or bracket) of the facing material is inserted into a special rigid groove made on the guide already during its manufacture, forming secure lock. The presence of sliding fasteners in the CTS system and the special design of expansion joints make it possible to compensate for both thermal loads caused by temperature changes and deformation loads caused by shrinkage and movement of the buildings themselves without transferring forces to facing material and on the load-bearing anchor.

Fire tests conducted at TsNIISK im. Kucherenko, showed better results compared to systems with a stainless steel structure and rigid fastening of the brackets to the guides. As a result, the KTS-1VF ventilated facade system received permission for use in buildings of any class of structural fire hazard without height restrictions.

Composite facade materials

The parameters of the used materials are important for the fire safety of the FS. composite materials.

Thus, in article /15/ the results are considered experimental research VNIIPO EMERCOM of Russia fire hazard parameters of some aluminum composite panels(AKP) with fillers of various compositions. It has been established that in the automatic transmission the inner layer of polyethylene (the color of the automatic transmission filler is black or dark gray) releases gaseous combustion products at 6-8 minutes of testing and then ignites with the subsequent abundant appearance of burning melt drops. It is noted that the smoke generation coefficient of the ACP filler based on polyethylene classifies it into group D3, and the ACP itself into D2 (for high-rise construction you need D1), and in terms of flammability and flammability, respectively, to G4 and B1.

The scope of application of such ACPs is low-rise construction; for materials of the FR group it should be limited to building heights of up to 21 m (although up to 28 m could be allowed to comply with Russian standards for high-rise buildings), and for higher heights, galvanized steel frames with protrusions should be used beyond the plane of the facade.

In this case, it is advisable that the final decision on the possibility of using these materials in FS structures should be made only after fire tests. It is also indicated that the use of composite cladding in FS (in the form of flat or cassette three-layer elements 2-3 mm thick made of aluminum or steel sheet with a middle layer of non-combustible materials, for example, based on aluminum hydroxide), belonging to class A2 according to DIN 4102, does not pose a fire hazard. The scope of application of composite materials with a more complex composition of the middle layer, including polyethylene, resins, oxides and minerals, is limited by the design solutions of the FS. Their trade designation FR (refractory material) and compliance with the requirements for flammability group G1 do not guarantee their fire safety as part of the system.

/16/ discusses in sufficient detail the advantages of the ALUCOBOND material, consisting of two layers of aluminum alloy 0.5 mm thick and a plastic or mineral core 2-5 mm thick, which is reliable and lightweight (the weight of one square meter 4 mm thick is 7. 6 kg) and fire safety.

From foreign experience it is noted that as soon as the requirements for the degree of fire resistance and the class of structural fire hazard increase to the level C0 and K0, then when using composite materials of class K1 or K2, it is necessary to install fire barriers along the entire perimeter of the building made of galvanized steel and flame cutters made of the same galvanized steel - on each window opening protruding beyond the plane of the facade up to 50 mm. But in this case, the main advantages of mounted fire fighting systems disappear due to the need to carry out such fire safety measures.

One of the advantages of the ALUCOBOND A2 material is emphasized in that it allows you to make slopes and ebbs adjacent to windows and doorways without additional fire stops protruding beyond the plane of the façade, and in compliance with all FS principles on any buildings with the highest fire safety requirements.

/17/ discusses the use of aluminum composite panels (ACP). At the same time, the use of ALUCOBOND B2 (inner layer made of polyethylene, fire hazard indicators G4, B1, D2, T2) is allowed only for buildings of Y degree of fire resistance, ALUCOBOND B1 (inner layer based on aluminum hydroxide and resin, fire hazard indicators G1, B1, D2 , T1) is recommended for walls with openings no more than 18 m high, ALUCOBOND A2 (inner layer based on aluminum hydroxide, fire hazard indicators G1, B1, D1, T1) can be used for buildings of all degrees of fire resistance, functional and structural fire hazard. Attention is also drawn to the high probability of contacting construction market AKP – counterfeits and the need for identification control when using such materials at significant objects.

In /18/ it is also stated that the Yukon Engineering company produces and installs SVF using the U-kon system for the construction of buildings up to 100 m high, when fire safety is ensured by the use of non-flammable and low-flammable composite materials in combination with structural solutions fire protection and based on the results of fire tests.

In /17/ based on the results of fire tests and conclusions issued by the Center for Fire Research of the TsNIISK named after. V.A. Kucherenko, a similar conclusion was made that for buildings with a height of more than 30 m, automatic transmissions with the A2 index according to the European classification, as well as other automatic transmissions that have passed full-scale fire tests, should be allowed, subject to mandatory compliance with design solutions that have received a positive technical assessment from the above-mentioned organization .

There are also four types of automatic transmissions:

ALUCOBOND A2,

Alpolic FR/SCM,

Particular attention is drawn to the inadmissibility of making changes to design solutions that have technical certificates from the State Committee for Construction without appropriate approval, or applying solutions without conducting fire tests in accordance with GOST 31251.

In /19/ the started production of fire-resistant aluminum composite panels Kraspan-AL is described. The composition of the composite component of the automatic gearbox was developed jointly with specialists from the VNIIPO EMERCOM of Russia and contains 75% mineral filler, 20% binder polymer and 5% thermopolymer adhesive. It is noted that according to the test results, automatic gearboxes with 65% mineral filler were successfully tested in the city of Zlatoust at the testing ground of the TsNIISK named after. V.A. Kucherenko as part of a façade system with an aluminum substructure and basalt insulation.

The scope of application of AKP includes buildings and structures of all degrees of fire resistance, all classes of structural and functional fire hazard.

Thermal insulation materials

Fibrous heat-insulating materials with a density of 80-90 kg/m3 are recommended for use in non-aircraft structures. However, /20/ proves that, taking into account current trends in the production and use of fibrous thermal insulation materials more justified (both from a technical and economic point of view) is the use of fiberglass-based thermal insulation materials with a density of 15-20 kg/m3 in SVF, both in combination with fibrous materials with a density of 60-80 kg/m3, having windproof properties (two-layer version), and in combination with windproof membranes (single-layer version). It is noted that this approach was implemented in the joint venture “Design and installation of curtain facades with an air gap”, developed in the Republic of Kazakhstan using DIN 18516-1 standards “Ventilated cladding external walls" and ATV DIN 18351 "Performance of façade works".

In /10/ the use of a relatively new insulation for Russia for plaster FS - extruded polystyrene foam (XPS) - is considered. It is noted that the test results at WASKER plastering system TERRACO TERM with a thermal insulation layer STYROFOAM IB250A and components of a plaster facade showed that the system withstood 50 freeze/thaw cycles, and the adhesion index plaster layers to insulation was 240-290 kPa, which is 10 times higher than similar indicators for mineral wool, and the weight of FS is 18 kg/m2, which is 2-2.5 times lighter than FS with mineral wool. The impact strength indicator is up to 330 kN/m2.

Regarding fire hazard: XPS, as a material, is a flammable, self-extinguishing (in the presence of fire retardant additives) insulation with a flammability rating of G1.

Full-scale fire tests of wall structures with plaster composition, carried out at the Fire Resistance Certification and Testing Center - TsNIISK with the participation of VNIIPO specialists, showed:

fire hazard class of the KO system according to GOST 31251 and fire resistance limit REI60 according to GOST 30247.1-94 with a thickness of STYROFOAM IB250A insulation up to 120 mm.

A number of features of the use of FS

The obvious advisability of taking into account the differences in requirements for FS structures with significant differences in temperature conditions outside the building and on the premises (including fire hazards), i.e. frost and heat resistance;

Justification of additional requirements for fire-resistant glazing of window openings and side facings window slopes, the need to assess the resistance of interlayer gel filling or filling with inert gas to UV radiation and exposure to negative temperatures.

Fire prevention measures

Based on the analysis, the following additional (compensatory) solutions can be proposed as fire prevention measures:

1. The use of fire-resistant glazing belts at the floor heights above and below the fire-resistant ceiling (an alternative to canopies and projections). The corresponding products of foreign and Russian companies are actively offered on the domestic market - for example, Pirobatis (Slovakia), SCHUCO (Germany), REYNAERS (Belgium), Glaverbel concern, Fototech LLC, Glass company, fire-technical information -testing center (Moscow) – fire-resistant laminated glass with gel filling, having a fire resistance limit of EI 15, 30, 45, 60, 90 and 120 minutes. During a fire (when the temperature reaches about 120 degrees), the intermediate layers successively change their physical characteristics and the glass turns for a certain time into a rigid and opaque structure that provides the necessary protection.

2. Fire requirements to the glazing frame material. It should be taken into account that aluminum alloys (their advantages, in particular, are relative cheapness, durability, low weight) easily melt already at 500 degrees C and corrosion-resistant or stainless steel is more acceptable as base material VFS frame.

However, according to a number of experts, the future lies with aluminum profile systems, which take into account all modern market trends and which have a number of advantages compared to the traditional post-transom structure.

A solution to the issue in /20/ is that the fire resistance of aluminum profiles is ensured by filling their central chambers with heat-resistant and heat-absorbing compositions. This makes it possible to compensate for the bending moments that occur during one-sided heating of the structure during a fire, which leads to its minimal deflections and increases the resistance of the FS to high-temperature effects.

For FS, in which aluminum guides are used as a frame and cladding is made of ceramic slabs, it is recommended to use a combination of steel and aluminum guides. In this case, steel guides should be installed above the window openings and in close proximity to the vertical slopes. Use in FS aluminum alloys with more high temperature melting leads to a significant reduction in the fire hazard of FS and expansion of the scope of their application.

3. The use of fire-resistant cuts or belts with a height of at least 1 m in facade systems (in areas of interfloor ceilings, especially in places adjacent to fire-rated ceilings), as well as limiting the use of insulation:

Expanded polystyrene – up to 12 floors,

Mineral and silicate systems – up to 25 floors,

The rest is subject to additional agreement at the design stage;

4. Ensuring that the brackets of façade systems are attached directly to the floor slabs, especially when filling the concrete frame with foam and gas blocks (for them, the “pull-out” force of the anchor is at least 2 times less than in the case of brick or concrete), the use of which should be limited by height up to 75 m (an additional requirement that provides higher mechanical strength that prevents the destruction of the façade or separation system from loads in emergency conditions, which avoids additional casualties and destruction).

5. Availability non-flammable insulation and ensuring resistance to smoke penetration (by analogy with other structures - at least 8000 kg/m per 1m2) in the areas between facade systems and interfloor ceilings.

6. Use of foreign experience in sprinkler irrigation of facade glazing (from the inside using cornice-type sprinklers), although the scope of application of such a solution is limited, especially in winter time. However, /21/ mentions research showing that specially tempered, ceramic and gel-filled glass can withstand the “cold shock” caused by sprinklers.

Other problems of using FS

Let's also look at some of the regulatory requirements when they are formulated without regard to use modern technologies and design solutions for facade (especially glazed) systems:

1. When rescuing people or extinguishing a fire, according to the operating instructions for fire trucks, the upper part of the ladder should, as a rule, rest on the structure of the building. This load (static and dynamic) is not taken into account when calculating glazed facades and their frame. It can be assumed that these actions will be accompanied by the destruction of the glazing, and then it is unclear how this will affect the integrity of the façade system as a whole and whether its progressive destruction will occur. This is especially significant when using aluminum systems in the frame, the strength characteristics of which are lower compared to a steel frame. In this regard, we can note the need for periodic revision (possibly once a year) of SVF structures.

3. In addition to technical solutions to ensure the maintainability of facades, devices for cleaning and washing translucent fences, the RD should provide requirements for embedded structural elements for the use of individual or group means of rescue and self-rescue. So, according to /22/ in buildings:

20 floors high evacuation time according to staircase is 15-18 minutes,

30 floors high – 25-30 min.

Insufficient reliability of smoke ventilation systems can make evacuation from high-rise buildings using stairs completely impossible. Therefore, when designing, it is necessary to provide means of rescue (used by firefighters) and self-rescue (used by people in danger), including one feature that must be taken into account - in the event of a fire, people who find themselves in the dangerous zone of the fire floor often only need to go down 1-2 floors below to be in relative safety, for which folding rescue ladders, rope descent devices, etc.

For rope descent devices, the difficulty lies in the lack of places on buildings for their fastening; this is also not included in the standards.

At the same time, the composition of constructive solutions for facades when such requirements will be met remains unclear.

For example, this component is not yet provided for in load calculations, but only its static component (according to SAMOSPAS LLC) will be at least 300 kgf. It would also be necessary to evaluate how applicable this is from the point of view of the architectural appearance of the facade and how to practically carry out periodic testing such a system, as well as use it during fire and rescue exercises.

4. When the height of public buildings and structures is more than 50 m, and for residential buildings - more than 75 m in accordance with Article 17 of Federal Law No. 384 /23/, fire safety requirements should apparently be justified primarily by calculations, including calculation of the dynamics of fire hazards on the facades of buildings, which is used to justify the placement of air intake devices for smoke ventilation systems and measures to protect against the entry of combustion products into air pressurization systems.

It seems that the use of facade systems, especially glazed ones, will require changes to the existing methods of such calculations and (or) tests, especially in relation to SVF and glazed atriums, the height of which (according to standards) may be limited to more than 50 meters.

Conclusions:

1. In the regulatory documents, the necessary requirements for fire safety, including fire safety, are clearly insufficiently reflected, including assessment of the possibility of fire exposure from outside the building (an option in connection with the threat of terrorist acts, burning of materials stored near the building, installation structures and so on.).

2. To confirm the possibility of using a specific IAF system, it is necessary to provide a Technical Certificate, where, upon its annual renewal, appropriate changes and additions must be made in a timely manner based on new results of scientific and experimental research. At the same time, within the framework of Gosstroynadzor, strict quality control of the implementation of the required fire-fighting measures is necessary, the compliance of the actually used illegal armed forces and their elements with those that have passed fire tests and are approved for use.

18. Ventilated facade systems. “Stroyprofil”, 2005, No. 7(45). – P.30.

19. Kosachev A.A., Korolchenko A.Ya. Fire danger hanging facade systems. “Fire safety in construction”, 2011, August. – p.30-32.

20. Galashin A.E., Baskakova L.Yu. Fire-resistant translucent structures in a complex of measures for fire safety of buildings. “Fire safety in construction”, 2006, June. – P.29-31.

21. Goncharenko L.V. Fire resistant glass. “Fire safety in construction”, 2005, No. 8. – P.8-12.

22. Terebnev V.V. Fires in high-rise buildings: how to save people. “Fire safety in construction”, 2005, No. 12. – P.16-19.

« Where there is uncertainty, imagine horror.”

Andrey Tomantsev. Soldiers of fortune

A problem when designing systems of suspended ventilated facades (like any other new system) is a very limited number of data and requirements in unified state standards (SNiP, SP, GOST, The federal law) and availability large number disparate documents developed for specific products.

These documents include a technical certificate + technical assessment, a book of technical solutions, design recommendations and some others, for example a fire certificate, a conclusion on corrosion resistance, seismic resistance tests.

According to the Decree of the Government of the Russian Federation of December 27, 1997 No. 1636, new materials, designs and technologies are subject to confirmation of suitability for use in construction. Suitability of new construction products confirmed by a technical certificate (TC) of the Ministry of Regional Development of Russia. The technical certificate for suspended facade systems reflects: the purpose and scope of application of the structures, a fundamental description, parameters, indicators and technical solutions of the structures, additional conditions for quality control of installation and conclusions about the suitability of products and the permitted scope of application.

Another document for the design and calculation of a ventilation façade is recommendations for the design of suspended façade systems with an air gap. The recommendations contain: basic provisions on the scope of application of systems and constructive solutions; methods of strength, heat engineering and heat and humidity calculations of a ventilated façade; provisions for installation and performance indicators. These documents are methodological and reference manual in the preparation of projects, developed by the Central Research and Design Institute of Residential and Public Buildings TsNIIEP Dwellings and approved by the instructions of the Moscow Committee for Architecture. In form, the recommendations are more similar to regulatory documents such as SNiP for ventilated facades or GOST.

Strength and other calculations of a ventilated facade in accordance with the Recommendations can be performed using a program for calculating facade systems.

All of the listed documents (Albums of technical solutions, technical equipment, Recommendations and fire reports) can be downloaded by subscribing to the VKontakte blog page in the panel on the right.

Everyone understands the need to introduce a single normative document in relation to systems of suspended ventilated facades. The issue has been repeatedly discussed in publications and appeared at every round table dedicated to this topic. It is worth noting, however, that things do not stand still; in the new SP 50.13330.2012 “Thermal protection of buildings”, a method of thermophysical calculation of suspended facade systems with ventilated air gap. Let's hope that the higher comrades will soon get to a single document on ventilated facades.