Once upon a time there was an old man and an old woman, they had a daughter, Alyonushka, and a son, Ivanushka. An old man...
1.2. For fire protection of elements of wooden frames of enclosing structures, it is recommended to use flame retardants for deep impregnation of wood under pressure and applied to the surface.
1.3. When choosing a flame retardant composition for specific application conditions, one should take into account their technological (Table 1) and operational (Table 2) indicators.
| Indicators |
OFP-9 |
WP9 |
MS 1:1 |
THEF |
|
| Composition consumption, g/m2 |
500-700 |
700 |
66* |
600 |
|
| Coating thickness, mm |
0,6-0,8 |
0,2 |
- |
- |
|
| Temperature and humidity conditions of the environment during application |
temperature, °С |
from 10 to 50 |
from 10 to 35 |
without Borders |
at least 20 |
| relative humidity, % |
less than 75 |
less than 80 |
no more than 65 |
||
| Maximum moisture content of wood during application, % |
16 |
15 |
30 |
15 |
|
| Application method |
recommended |
pneumatic atomization |
vacuum-atmospheric pressure GOST 20022.8-76 |
heating with dry air - cold bath GOST 20022.6-76 |
|
| unit "ANSH-1" |
installation "Shield" |
||||
| allowed |
brush, roller |
hot-cold bath |
brush, roller |
||
| Possibility of gluing protected wood surfaces |
not allowed |
allowed |
|||
* The consumption rate of flame retardant MC 1:1 is given in kg/m3.
| Indicators | OFP-9 | VPD | MS 1:1 | THEF |
|
| Temperature and humidity operating conditions | temperature, C relative humidity % | A 1 | A1 and A2 | without Borders |
|
| according to SNiP 11-25-80 |
|||||
| Aesthetic qualities of a protected wood surface | opaque, uniform, matte, gray | opaque, uniform, matte, gray or white | the texture and color of the wood does not change |
||
| Effect on wood strength | does not affect | reduces compressive strength along the fibers and in bending by 10% | does not affect |
||
| Influence on corrosion of metal structural elements | does not affect | promotes corrosion of ferrous metals | does not affect |
||
1.4. In accordance with the note of SNiP II-2-80, chapter 3, table 1, in buildings, industries of category B, glued beams, trusses, arches, frames and columns of buildings and structures should be used with fire retardant treatment.
1.5. In accordance with the note SNiP II-2-80, Chapter 3, Table 2, wooden slabs, floorings and girders of buildings and structures, as well as elements of hinged panels of external walls and internal load-bearing walls (partitions) of these buildings and structures must be subjected to deep impregnation with flame retardants.
1.6. Information about the fire resistance limits of the most common wooden structures, including plastered ones, is given in the "Guidelines for determining the fire resistance limits of structures, the limits of fire propagation along structures and the flammability groups of materials", M .: Stroyizdat, 1984.
1.7. Fire-retardant treatment does not reduce the rate of charring of wood and does not increase the fire resistance of wooden structures with a cross section of more than 120-120 mm. The use of flame retardant treatment can reduce the spread of fire through wooden structures or transfer wood to a group of fire-retardant materials.
1.8. The quality of the flame retardant treatment should ensure that the limit of fire propagation along wooden structures is reduced to 40 cm for vertical elements, to 25 cm for horizontal elements, or the test results of protected wood according to ST SEV 2437-80 must meet the requirements for slow-burning materials.
2.1.1 The coating should be used for fire protection of structures operated indoors with a non-aggressive environment, a positive temperature not exceeding 35 C, and a relative air humidity of not more than 60%. It is allowed to apply the coating at a relative air humidity of not more than 80%, provided that a moisture-protective layer is applied to the surface of the dried coating.
2.1.2 The materials for the preparation of the coating composition, as well as the technology for its application to structures, must meet the requirements given in the mandatory annex.
2.1.3 The coating must be continuous and not have cracks, delaminations, swellings. The surface finish of the coating must be carried out in accordance with the design.
The coating composition is delivered to the place of work in the form of two components: paste and ammophos, mixed before being applied to structures to obtain a working coating composition.
2.2.1. The paste should be transported at a temperature of minus 40 to plus 40 C for no more than 1 month and stored at a temperature of minus 5 to plus 30 C for no more than 6 months with obligatory protection from atmospheric precipitation.
2.3.1. The preparation of the working composition of the coating should be carried out at the place of work immediately before application to structures.
2.3.2. To prepare the working composition of the coating, the paste is mixed with ammophos in mortar mixers of types SO-26b, SO-23b, SO-46a in a ratio of 7.25 parts of paste, 2.75 parts of ammophos, and then twice passed through a paint grinder of types SO-110, SO -116.
2.5.1 The application of the coating composition should be carried out by pneumatic spraying using installations for applying liquid putties of the C-562a type according to the normative and technical documentation approved in the prescribed manner.
2.5.2 The application of the coating composition should be carried out in 2 layers. The rate of the total consumption of the working composition of the coating, taking into account production losses, should be 750 g per 1 m2 of surface.
2.5.4 On the dried coating, not earlier than 4-5 days after applying the second layer, as a moisture protection or decorative finish, if they are provided for by the project, any of the pentaphthalic enamels of the following brands should be applied: PF-115 according to GOST 6465-76 , PF-223 according to GOST 14923-78, PF-218 according to GOST 21227-75; enamels based on vinyl chloride copolymers grades: ХВ-785 in accordance with GOST 7313-75, ХВ-124 in accordance with GOST 10144-74 or organosilicon enamel grade KO-174 according to normative and technical documentation approved in the prescribed manner.
The application and drying of enamels is carried out in accordance with the standards and other regulatory and technical documentation approved in the prescribed manner for these types of enamel.
| Name of composition, brand | GOST, TU | Compound | Content by weight, % | Solvent |
| 1 | 2 | 3 | 4 | 5 |
| Fire retardant coatings |
||||
| Coating for wood fire-retardant phosphate OFP-9 | GOST 23790-79 | Sodium polymetaphosphate | 40 | Water |
| aluminum hydroxide | 15 |
|||
| Kaolin or clay | 5 |
|||
| Fly ash from TPP | 15 |
|||
| Iron minium or zinc oxide | 5 |
|||
| Urea or thiourea | 20 |
|||
| Coating for wood intumescent fire retardant VPD | GOST 23130-82 | Melamine urea formaldehyde resin MMF-50 | 31,9 | Water |
| 5% aqueous solution of sodium salt of carboxylcellulose (grade 85-500) | 15,9 |
|||
| Melem | 18,4 |
|||
| Dicyandiamide | 6,3 |
|||
| Ammophos grade A | 27,5 |
|||
| Impregnation compositions |
||||
| An aqueous solution of a mixture of diammonium phosphate, ammonium sulfate and sodium fluoride MS 1:1 | Instructions for flame retardant and harvesting of lumber by deep impregnation with a solution of flame retardant in an autoclave at the enterprises of Glavmospromstroymaterialov VSN 74-79, Moscow, 1980 | Diammonium phosphate | 7,5 | Water |
| Ammonium sulfate | 7,5 |
|||
| sodium fluoride | 2,0 |
|||
| Water | 83,0 |
|||
| Solution of trichloroethyl phosphate in carbon tetrachloride TCEP | Trichloroethyl phosphate TU 6-05-1611-78 | 40 | carbon tetrachloride |
|
| Carbon tetrachloride GOST 4.75 | 60 |
|||
on liquid glass:
surfaces
including:
TU 2311-001-23063581-95
Today, natural wood is actively used not only in the manufacture of furniture, but also in construction, as it has been for many centuries. Wood is an excellent building material, but it has a serious drawback - susceptibility to fire. Fortunately, for the protection of structures made of wood, fire impregnation for wood is now offered.
Protection of wood from fire is the main fire safety requirement for each building or structure, and it does not matter during direct construction or during operation. The norms set forth in local and regulatory documents must be observed, otherwise the facility will not be put into operation. This is a prerequisite for specialized construction organizations.
When building a private house, any owner must also provide for covering wooden structures from fire, this requirement is not in vain provided.
Fire impregnation of wood is carried out with the following frequency:
- before putting the facility into operation;
- every 5 years;
- as necessary, if during operation the properties of the impregnation do not provide protection.
The latter is checked very simply: you need to remove a small section of the chips and set it on fire and, accordingly, in the event of a fire, treatment with a flame retardant is necessary.
Fire protection of a wooden base is a measure to ensure fire safety requirements, which must be carried out on the territory of the entire Russian Federation.
List of wood processing methods:
- Performing finishing works using special fireproof materials.
- Measures to increase the fire resistance limit.
- Fire-retardant impregnation for wood using paintwork.
- At the design stage, it is chosen which method to apply to a particular structure. The inspection is carried out by a representative of the fire service.
Fire retardant treatment is required for the following items:
- roof structures (bearing and non-bearing);
- timber walls;
- coatings and ceilings;
- beams;
- shingles for plaster;
- wooden panels inside and outside;
- other wooden surfaces.
On the video: fire-retardant wood treatment.
Types of impregnations
The fire retardant composition for wood is selected based on the following parameters:
- Areas of use;
- destination.
In total, there are 3 types of impregnations from accidental fires or fires of wood materials: acid, alkaline, saline. In this case, specialized flame retardants, paints, varnishes or enamels are used for surface treatment of wood. After their application, a thin layer is formed. Aqueous salt solutions are used for deep processing of structural elements.
Although these methods are widely used in practice due to their effectiveness, fire-fighting treatment is also very successful. It not only meets the requirements of PB (fire safety), but also fully guarantees:
- providing a high level of protection;
- processing efficiency for a long time;
- the invariance of the choice of color solution;
- compatibility with almost all further coatings;
- safety for both nature and people or animals.
Acid formulations
This is the best solution for impregnating wood from fire. This does not change the color of the material, and its structure remains the same. The acid agent provides additional strength to the structural element, while the wood “breathes” and fully retains its properties. A huge range of products is available in retail outlets.
Alkaline compounds
The effectiveness of the use of such impregnations is low due to the violation of the structure of the tree, therefore they are not recommended for treating visible areas. Such formulations are commercially available and their price is low compared to acid solutions.
Saline solutions
These compounds are not as effective. After processing, salt stains appear over time, which not only spoil the appearance of the tree, it becomes necessary to carry out the processing again. As a rule, for outdoor work, the validity period of such a coating is no more than 2 years, and for indoor - no more than 5 years.
Salt solutions are easy to prepare yourself, the only negative is that you can not calculate the proportions.
Fire retardant impregnation of wood on any basis contains substances that melt when ignited, while forming a thin film, which in turn provides an obstacle to oxygen. Impregnation compositions based on alkalis, in direct contact with fire, produce gases to prevent the persecution or spread of fire.
A preparation based on carbamide or furan-carbamide resins has gained great popularity, since not only fire resistance is provided, but also direct resistance to the perception of mechanical loads.
Among other things, the fire retardant preparation is divided into:
- resistant to external manifestations - for outdoor work;
- unstable to atmospheric factors - for internal work.
Today, there is a whole range of flame retardants on sale, which provide fire protection properties.
Application of fire retardant paint
The very principle of impregnating wood from fire by painting is somewhat different from the direct effect of impregnation. Coating with antiseptic and fire-fighting compounds provides a layer to prevent heating and further ignition of the structure. Upon reaching the ignition temperature of wood, water and an inert gas begin to be released. In addition, modern fire-retardant paints for wood have 2 functions at the same time:
- from decay;
- from fire or high temperatures.
Applying fire-retardant paint to the surface is carried out using rollers, brushes or using an airbrush. The very frequency of wood treatment with a fire-retardant coating is indicated by the manufacturer on the packaging, and even reaches up to 10 years.
The principle of operation of protecting wood from fire:
| Name of the main property of the paint | Efficiency | Flammable properties | Note |
| intumescent | 1st efficiency group | During the period of direct influence of open fire, the pores formed by the paint crack, while the release of water and gas occurs in parallel, including the expansion of the non-combustible layer. | Depending on the selected material, the thickness of the intumescent layer changes upwards and ranges from 10 to 40 times. |
| Not intumescent | A layer that provides thermal protection is present initially. The composition of the material includes liquid glass and fillers to create fire protection, as well as flame retardants. | Wood flame retardants in this category actively resist fire for up to 2 hours. | The fire safety class of wood is increased by 1 step. |
Compositions for wood that provide fire protection are easy to choose in the store, according to the characteristics of the manufacturer.
Fire retardant varnish properties
This paintwork material has all the properties for fire protection, as well as its functional purpose - for decorative application. When choosing in favor of this product and using it, the structure of the wood is preserved.
Refractory impregnation with varnish is used not only for processing the wood from which the structure is built, but also for covering furniture, wooden floors, laminate and other surfaces.
The main properties of this varnish include the following:
- composition for wood provides fire resistance of the structure for a period of 6 to 10 years;
- it is possible to apply on a previously painted surface, except for a previously applied water-based coating;
- performance of work with fire-resistant varnishes should be carried out at a temperature of at least +5 degrees;
- wood processing after application increases fire protection;
- fire protection varnish can be matt or semi-gloss.
Such fire and bioprotective impregnation is fully consistent with non-expanding materials. In this case, it is not necessary to apply an additional layer of antiseptic.
additional information
Wood processing is necessary, and there is other important information about this:
- Fire-retardant materials for wood, despite their relatively high price, quickly pay off, especially since their consumption per 1 m 2 is not so high. This characteristic is specified by the manufacturer. In addition, there is also an antiseptic in the composition.
- The preparation intended for processing must have a certificate of conformity.
- Fire retardant treatment at enterprises is carried out by specialized organizations.
- The impregnated flame retardant layer will last a long time.
- The resulting fire will not affect all structures.
- The purchased drug should not be saved when applied, otherwise the desired effect will not be ensured.
Fire protection of wood. Experiment (1 video)
Fire safety requires compliance with certain norms and rules when building various objects made of wood. The relevant services, before putting the building into operation, must check its compliance with GOST and SNiP. Such rules are required to comply with the owners of private houses.
Properly performed fire protection of wooden structures helps prevent the rapid spread of flames and protect structures from destruction. These are the mandatory requirements of the fire service, which are detailed in PPB 01-03. In apartment buildings, impregnation of wood and other structures with fire-retardant materials is assigned to special services. The owners of their own home can do such work on their own. The subtleties of this process must be considered by every property owner.
General information about processing
It is a set of measures that are used to reduce the combustible properties of wood and other materials. This procedure is performed in several ways.
Facing and finishing of wood products can be processed using refractory compounds. If necessary, changes are made to the structure of the building, which increase the fire resistance. Solid wood can also be treated with special paints and varnishes (LKM).
When designing a building, decisions on the use of certain protective equipment are made by qualified specialists. Therefore, when building a private house, it is necessary to draw up a house plan in accordance with all the norms of SNiP. At the same time, the project calculates exactly what measures will be applied during the construction of the house, what means will be used in this case. Next, a processing estimate is drawn up. An overview of this process should be known to every property owner.
An inspection upon completion of construction work is carried out by a representative of the Ministry of Emergency Situations or an independent expert of appropriate qualification.
Fire protection groups
The quality of processing during the construction of a new building regulates GOST. Fire protection of wooden structures can be divided into 3 groups. When the object is handed over, a representative of the Ministry of Emergency Situations takes samples of the material. This way you can determine the compliance of the processing with the stated requirements.
1 group of fire protection efficiency of wood is assigned at the maximum level of resistance to fire. The weight loss of the material is only 9%. When tested, such wood does not burn for up to 150 minutes. Such protection is used in crowded places.
Group 2 is established if during testing the material lost weight by 25%. Such wood is also called flame retardant. The resistance of structures to fire in this case is 90 minutes.
Group 3 belongs to the fire retardant color. Fire protection is minimal. This treatment is used for private houses with low requirements for the fire resistance coefficient.
Impregnation
One of the most popular flame retardant materials is impregnation. The rules for its selection and application are described in detail in the relevant SNiP. Fire protection of wooden structures by impregnation can be divided into two ways. This is superficial and deep processing.
In the first case, the cost of the work performed will be slightly lower. Therefore, this approach is very popular. With a brush, roller or spray gun, the composition is applied to the surface of wooden structures. Such agents include flame retardants. Such products do not penetrate deep enough into the pores of the wood, which limits their protective properties.
Deep impregnation is considered more effective. The material is processed under pressure. To do this, use a hot-cold bath or autoclave. If the work is done at home, the wood is soaked in a container. Then the timber is dried. The entire process must be carried out strictly according to the manufacturer's instructions.
Environmental conditions
One of the most effective ways to impregnate wood is vacuum application of the product. This requires heating up to 60 ºС and a pressure of 8 atm. However, even this method cannot guarantee that the product will not lose its properties during operation under the influence of environmental factors.
For example, fire protection of wooden roof structures, attic and other open structures in winter require the use of special compounds. Such compositions must be resistant to washout. Under the influence of atmospheric phenomena in such conditions, the agent should not be washed out of the structure of the material.
Distinguish between washable and non-washable products. The effect of moisture on the material must be taken into account when choosing a suitable product.
fire retardant paint
Works on fire protection of wooden structures can be carried out independently if a small private house outside the city, a cottage is being built. In this case, wood can be treated with special paint. It creates a protective layer on the material. It prevents heat and fire. When the ambient temperature rises, such paint releases water and inert gas.
Such a tool additionally protects wood products and structures from decay and destruction. The paint can be applied with a roller or spray gun. Periodically, the coating must be updated. The frequency of such procedures is indicated by the paint manufacturer. Usually this figure is at least 10 years.
Fireproof varnish
Can be created with a special varnish. It also allows you to create a decorative coating on the surface. The natural structure of wood is preserved in its original form. Therefore, such material is used in the processing of floors, furniture, laminate, etc.
The frequency of renewal of the lacquer coating is about 6 years outside. If the processed objects are inside the room, such work is carried out once every 10 years.
Lacquer coating can be matte or semi-matte. The material must be applied in several layers. The hardening time of each of them is 12 hours. The more layers will be applied, the greater the fire safety of the material.
Other flame retardant materials
It can be done with special materials. These include sheets of drywall (GVL), roll insulation, refractory belts, as well as additional frame structures.
GVL materials of a non-combustible type are able to limit the effect of heat on fire on supporting structures. Such plates are used when it is impossible to apply impregnations or paints and varnishes.
Foil insulation is used in hard-to-reach places, attics or attics. Fireproof belts help prevent the spread of fire. Their location is developed at the design stage of the building.
Bearing structures can be protected from fire with a brick frame or stucco refractory mixture.
Cost of work
Has different cost fire protection of wooden structures. Price per m2 depends on the processing material. The class of fire protection is also taken into account. If the owner of the property resorts to the services of specialized companies, then when treating wood with varnish, the cost will be 480-500 rubles / m², and with paint - 400-450 rubles / m².
Surface impregnation of materials for attic spaces inside will cost 20-30 rubles / m². If it is necessary to process external structures, walls, then weather-resistant impregnation will cost about 500 rubles / m². If the surface spraying method is used for its application, the price will be lower - 340-350 rubles / m².
When calculating the cost of the services of a particular company, one should also take into account the quadrature of the treated surface. If it is less than set in the price list, the price will be set individually, and may be higher.
Choice of remedy
Fire protection of wooden structures (price for the work indicated above) can be purchased independently. If the owner of a private house wants to impregnate or apply a special paintwork, you need to pay attention to some important issues.
First of all, you need to calculate the consumption of funds per 1 m² of surface. It happens that more cheap funds are required, so the total cost of the work will be higher than when using the average cost of funds. In addition, cheaper products take longer to dry. Processing in this case can be very delayed.
On average, when applied with a brush or spray, wood absorbs about 150-180 g per 1 m² of surface. When choosing a product, be sure to read the manufacturer's information on the use of the composition.
Required documentation
To checking the fire protection of wooden structures was successful, when buying, you need to pay attention to the accompanying documentation. In our country, the sale of fire fighting compositions without certificates of conformity and conclusions of the sanitary and epidemiological station is prohibited.
Before buying a product, you need to pay attention to the fire safety class that this composition provides. If it is lower than required, it cannot be purchased. It is also desirable to consider the composition and method of application of the product, the level of its absorption by wood.
The service life of the coating, as well as its tinting qualities, deserves attention. If you have all the necessary documentation, as well as the compliance of the composition with the requirements of the project documentation, it can be purchased for use at your facility.
A responsible approach to the choice of fireproof protection will help to avoid damage to property, as well as protect the owners of the house from accidents associated with fires of wooden structures.
Loved by mankind for its strength and natural beauty, wood is afraid not only of moisture and dampness - it is also very combustible. For centuries, people have been looking for how to protect their homes from fire, inventing various solutions and techniques to minimize the combustibility of wood and reduce fire damage. To this end, various non-combustible substances were added to building compositions for the purpose of fire-retardant treatment of wood. Gradually, fire-resistant varnishes, paints and impregnations appeared.
How fire protection works
Protection of wood from fire is possible in two ways:
- Flame retardants, which include low-melting substances (salts of silicic, boric or phosphoric acid), melt when heated, forming a resistant film that does not allow air to pass to the wooden surface. Due to this, the ignition temperature of the tree is significantly increased, and hence its fire resistance.
- If the fire-fighting mixture contains ammonia or other similar preparations, then during a fire they release gases that suppress the flame and push oxygen away from the surface of the wood.
Varieties of mixtures
All compositions, depending on the basis, can be divided into:
- Paints. They provide good protection by coating wood products with a dense and durable film. Cons: hide the beauty of the surface; toxic. It is good to use them for fireproof protection of old buildings.
- Lucky. They emphasize the beauty of a wooden surface, reliably protect it from fire, but due to toxicity, they are not suitable for interior work.
- Impregnation - are used most often.
The latter need to be considered in more detail. Impregnations perfectly preserve the structure of the tree, penetrate deeply into the depth of the material, protecting it from fire.
Depending on the solvent can be:
- solvent-soluble - often toxic, used for outdoor work.
- water-soluble - non-toxic, suitable for treating walls inside and out.
Water-soluble impregnations are divided into:
- Easily washable. They are used in dry and moderately damp indoor areas, are well suited for living rooms, provide good protection in case of fire.
- Washable. They are used for processing living rooms and utility rooms with moderate humidity, they protect wood well from fire.
- Difficult to wash. Suitable for wet areas (kitchen, bathroom) and outdoor use.
- Non-washable compositions with increased flame retardant function. Well suited for external and internal processing of baths, saunas and other fire hazardous objects.
Processing methods
Impregnation of wooden fire protection products can be of different depths:
- Surface. As a rule, it is carried out on already finished objects. The composition is applied to a well-cleaned and degreased surface with a brush, roller or spraying, left to dry, and then other decorative woodwork is carried out. Fire resistance is moderate.
- Moderate. It is carried out by soaking in special baths, it is carried out even during the construction process. Provides good fire protection to the building.
- Deep, using an autoclave. Such impregnation is possible only in an industrial way, when the composition is driven under pressure deep into the pores of the wood. The resulting board has high fire and bioprotective qualities and does not require subsequent treatment with protective agents.
When choosing a method and solution for processing, it should be borne in mind that the deeper the composition penetrates into the base of the tree, the higher its resistance to fire will be. If it is possible to use autoclaved wood for construction, then it is better to build from it.
Degrees of protection
According to fire safety standards, the degree of protection of wood from fire can be:
- Maximum, first class. Such fire and biological protection is inherent in wood after autoclave treatment. Buildings made of such material are able not to catch fire under the influence of fire for up to 150 minutes.
- Average, second grade. The treated wood becomes difficult to ignite, able to resist flames up to 90 minutes. Such stability is achieved by soaking the board before construction in a bath with a flame retardant composition.
- Low, third class. This is achieved by surface treatment of buildings with solutions, which is typical for private residential buildings.
Self-protection of the building from fire
Unfortunately, it is impossible to give the finished building the first and second class of protection of wood from fire. But the composition chosen depending on the purpose will help to significantly reduce the fire hazard. When choosing an impregnation, you must consider:
- Heating capacity of the room. For attics, verandas, as well as for outdoor work, frost-resistant compounds must be taken.
- Influence of atmospheric factors. For the street, hard-to-wash mixtures are needed.
- Environmental friendliness. For residential premises, only non-toxic preparations are suitable, and when working with toxic ones, it is necessary to use protective equipment.
- Aesthetics. As a rule, impregnating agents do not affect the color and texture of the wood in any way.
- Profitability.
- Fire safety. The instructions for use should indicate the protective degree of the drug.
- Sustainability. How much time should elapse before further processing.
Applying flame retardant preparations to a wooden surface is easy. It is carried out in the same way as when using other types of impregnations:
- All impregnation works are carried out at positive temperatures in calm weather or in a well-ventilated area. Working at negative temperatures will reduce the absorbent qualities of the wood surface and reduce the protective properties of the solution.
- The boards are cleaned of old paint, dirt and dust.
- If possible, degreasing with white spirit is carried out.
- The solution is evenly applied to the prepared area with a brush, roller or spray gun.
- The surface is dried and the final decorative and construction work is carried out.
Tip: the fire-retardant qualities of the treatment carried out can be checked independently. To do this, from different places of the wooden structure, you need to take small chips and hold them over the flame.
Without constant exposure to fire, the sliver should go out. Carrying out fire-retardant impregnation of buildings is a responsible process that should not be neglected during construction or redecoration.
Proper application of flame retardants to wooden surfaces will increase the safety of a residential building. But it is worth remembering that even the highest quality preparations applied by a surface method, after a couple of years, under the influence of atmospheric phenomena, reduce their protective properties. They will need to be reapplied.
Despite the variety of modern materials, wood remains popular among our compatriots. But there is one negative nuance: the wooden coating can be destroyed due to fire. For this reason, it is necessary to treat wooden structures with a flame retardant (it is also called a fire retardant).
The principle of action of flame retardant materials is based on the physicochemical processes that occur with the components that make up fire retardants. The main components of fire fighting compositions are:
- fusible substances (salt solutions of boric, phosphoric or silicic acids);
- substances that emit gas (ammonia or sulfur dioxide).
When fusible substances are heated, a film appears, due to which oxygen cannot reach the surface of the wooden coating. As a result of this process, the ignition temperature of wood increases. This improves the fire resistance of the material.
Due to the use of substances that emit gas, the combustion process itself is suppressed. The non-flammable gas protects the wood from fire by removing oxygen from the surface.
Flame retardants are divided into:
- coatings;
- impregnation.
There are the following features of the material application:
- applying varnish can be done on a painted surface (with the exception of water-dispersion compositions);
- the process is carried out at a temperature of more than +5ºС;
- applying several layers of varnish occurs with a time interval of at least 12 hours;
- the frequency of varnishing wood is 6-7 years.
The only nuance that should be taken into account when purchasing paint and varnish products is their intended purpose. For outdoor work, only facade materials are suitable, which are characterized by increased wear resistance and fire protection.
Alternatives
In addition to impregnations and paints and varnishes, the fire-fighting properties of wood can be improved by using:
- materials with which a refractory crate is created;
- other constructive solutions.
Among the fire-retardant materials, gypsum fiber sheets should be noted. Due to the incombustibility of the material, the effect of heat on the supporting structure is limited. But there is a condition - all profile elements must be treated with a special solution without fail. It is most advisable to use gypsum fiber only in cases where it is impossible to carry out the application of a flame retardant composition.
The use of rolled fire-fighting material (foil insulation) is the best solution for fire protection of wood located in hard-to-reach places (attic floors, attic, other rarely visited premises).
A constructive solution is the creation of a refractory belt (or rather several), which will become an obstacle to the spread of fire. The places with the highest probability of a fire are determined. After that, refractory belts are created near them. In some cases, it is better to use a plaster mixture with vermiculite or additionally build a reinforced brick frame.
Conclusion
You can check the quality of wood processing by:
- visual inspection of the structure;
- selective examination of the integrity and thickness of the layer of several sections.
Checking with the use of fire is carried out using PNP-1 sensors. Based on the results of the research, acts are drawn up that allow the operation of the facility.
You can also check the quality of the fire-retardant layer yourself. For this:
- a sample up to 1 mm thick is cut from the treated area with a knife;
- using a lighter, the sample is ignited from the side where the flame retardant is applied;
- the workpiece should not support combustion or smolder;
- after 20-30 seconds, the surface of the sample will turn black and charred (without the appearance of a flame).
For comparison, you can take a piece of wood that is not treated with a flame retardant. When you turn on the lighter, after 4-5 seconds, the workpiece will begin to burn.
Naturally, the combustion process directly depends on the type of wood. For example, oak chips are difficult to set on fire without impregnation. For this reason, all tests are carried out on a pine wood base, which is highly flammable.
Video about the treatment of a wooden structure with a fire retardant:
