How to find the best façade paint

Exterior paint must meet a number of requirements to adequately represent the exterior of the home. A reliable exterior paint formulation has resistance to weathering, moisture, scorch and abrasion. There is a wide variety of paints and varnishes available in stores. To understand what type of facade paint to choose for your house, it is necessary to understand the basic differences between one type and another and take into account the compatibility with the finishing material.

Important features of facade paints

Exterior painting with the help of facade paints is a modern solution to exterior design. This universal technique seems simple only at first sight - it is necessary only to choose a color, apply the composition and the house in a short time acquires a finished image. However, leaving aside the choice of coloring pigment for later, first of all it is worth paying attention to its physical properties. It is from them will depend the durability of the coating and the microclimate inside the house.

• Compatibility with the finishing material;
• Abrasion resistance;
• Elasticity index;
• Degree of steam permeability;
• Degree of water resistance;
• Resistance to contamination;
• biological protection;
• Degree of susceptibility to UV radiation;

Good paint - what is it?

The surface material can be neutral (wood, brick) or alkaline (lime-based plaster). In the first case, the surface of the base will not react chemically with the paint. In the second case, the contact of the alkaline material with the acidic environment of the solution causes the rejection of the paint layer and leads to the collapse of the walls. Therefore, it is necessary to pay attention to the compatibility indicator of the base with the type of composition, which is usually indicated on the package.

Other important criteria for choosing the paint for the facade - the degree of elasticity and abrasion resistance. The walls of a house are constantly exposed to various external and internal influences. When the room is heated and the weather is hot and sunny, the paint coating expands and shrinks when it freezes. In this case, the high elasticity of the paint compound, together with its abrasion resistance, does not allow deformation in the form of cracks on the surface and its crumbling.

Chemical Performance of Paints

Vapor permeability is expressed in terms of the ability of moisture to escape from the walls to the outside and is important in removing excess moisture from the walls of a building. A low level of vapor permeability leads to the accumulation of a condensation layer under the paint coat, which, when it freezes, causes the surface to peel and deteriorate. The optimum value of vapor permeability indicated on the package is from 130g/m2 per day.

Water-repellent property serves to protect the house from penetration of moisture into the depth of the finishing material and its accumulation in it. Water penetrated into the thickness of the wall covering expands when it freezes, which leads to the destruction of this material. And the accumulated moisture in warm conditions contributes to the spread of fungal microorganisms, which are already a biological threat to the structure. The degree of water resistance of the paint is assessed in the maximum permissible value as 50 gr/m2xh0.5.

Resistance to dirt is another important criterion. Natural and industrial dust deposited in a thick layer spoils the appearance of the building and makes it unsightly. In addition, dirt is particularly noticeable on light, bright and glossy coatings. By applying a paint mixture with a dirt-repellent composition, you can easily clean the surface with a stream of water or wait for a rain event. Self-cleaning properties have been found in silicone, polyurethane and acrylic paints.

What else needs to be considered?

Biological resistance does not allow fungal microorganisms to penetrate into the thickness of the finishing material, which leads to loosening of the composition and its destruction. In addition, the appearance of the building suffers - black and black-green stains appear on the walls and it is impossible to get rid of them. The fungal attack is particularly noticeable on wooden surfaces, which should be pre-treated with a fungicide before painting. The highest rate of biological resistance is observed in acrylic and lime solutions.

Ultraviolet rays falling on the treated surface destroy the color pigments. The color of the coating becomes dull, the composition dries and cracks. Acrylic mixtures are characterized by high protection against burning and cracking.

Types of facade paints

Facade paints presented in finishing stores are divided into several types and subspecies. Despite their great variety, if you understand the characteristics of each type, you can easily isolate the type that will meet all requirements. The main and distinctive element of all paint compositions is a binder, which, when applied to the surface, forms a strong film responsible for adhesion to the base of the walls.

In a hardware store you can ask the salesman which facade paint is better. The answer will be obvious - water soluble is better than organic soluble. This is the first division of all facade paints into 2 types. Water-soluble solution has a modern and environmentally friendly composition, without admixtures of harmful chemical and flammable substances. The solvent for them is water. However, water-soluble paints are divided into mineral and water dispersion.

Water dispersion paints

In the composition of this type, the main part is aqueous, in which the remaining particles are dispersed, i.e. appear as suspensions. Copolymers and concentrates of silicone resins are used in their production. These paints are environmentally friendly, dry quickly and are perfectly diluted with water to the desired consistency.

The group of water dispersion paints includes subspecies of paint compositions:

• Vinyl. The main advantage of this type is its resistance to chemical attack. However, this composition is characterized by a high degree of shrinkage during drying. This leads to its delamination if the walls are painted more than once. Water resistance is low compared to acrylic compositions. However, the cost is lower.
• Silicone. The main advantages of such paints, in which the binding component is silicone resin, are moisture resistance, dirt resistance and thermoplasticity. The latter is expressed in the preservation of a solid surface at high temperatures. The disadvantage of silicone compositions - in their high steam permeability. Therefore, it is better to use the coloring solution on brick and concrete bases.
• Acrylic. One of the most common types, which is easy to apply and has a high degree of adhesion to the surface. However, such compositions are poorly permeable to moisture, so they are more often applied to concrete. Acrylic paint is not compatible with silicate and lime coatings.

Mineral Paints

Their difference from the previous group of paints is their environmental friendliness. They have a high drying speed and excellent vapor permeability. The latter feature is possible due to the almost natural composition, consisting of natural minerals ground into powder. May contain a small amount of synthetic resins to increase color fastness and protect against external influences. Available in powder form to be diluted with water and other solvents before application to walls.

Mineral paints are represented by the following subspecies:

• Cement. The composition is resistant to external influences, steam permeable and resistant to alkaline materials. The disadvantage is the fragility of the dried solution and crumbling over time.
• Silicate. Made on the basis of liquid glass, highly resistant to weathering. However, they are difficult to apply and have a limited color range. They should only be applied to a clean surface or to the old silicate coating.
• Lime. The main component of the composition - slaked lime. When painting walls, it comes into contact with oxygen and carbonizes, which gives it its durability. It can be purchased in the form of powder or paste at a low price.

Compatibility with Facade Materials

The material of the facade and the paint to be applied to it must be compatible in terms of physical and chemical properties in order to obtain the durability of the paint solution and its adhesion to the substrate. Before deciding on the most suitable facade paint, it is necessary to consider the substrate to be treated:

• Wood. It is characterized by high rotting indicators, water permeability and fire resistance. For this material, it is necessary to choose a composition that has a high degree of adhesion with wood, waterproof and elastic. Such properties are possessed by acrylic colored and colorless compositions. The latter has two additional advantages - it perfectly emphasizes the wood texture and is more permeable to water vapor.
• Brick. This material has a tendency to release salts and eventually flake off. Therefore, the paint coating must be vapor permeable and flexible, resistant to precipitation, chemicals and damage. A paint compatible with brick is acrylic - breathable and resistant to moisture and salt release. Silicate paint is recommended for silicate brick, and any type of paint is suitable for ceramic brick.
• Foam block. A special porous material that absorbs substances from the surface. The coating must be permeable to water vapor and water repellent. These requirements are well met by silicone paints and a more expensive option - rubber. After application, there is a possibility that the coating will break down if holes and cracks are not properly sealed.

Tips for using facade paints

Based on the above, the main thing to pay attention to when choosing paint for the facade is compatibility with the base and its physical properties. In addition, it is necessary to know at what temperature to paint the walls of the house facade paint. Following these recommendations will help to achieve the best result and the expected effect of painting:

• Painting of facade walls is better to carry out at a plus temperature on the street. In these conditions the paint solution dries much faster and better than in cold weather. 
• - From 5 ° C - it is at this temperature you can paint facade paint walls of the house without experiencing difficulties with drying surfaces. In addition, the temperature range from -5 ° C to +5 ° C is unfavorable for wall treatment.
• - If you have to paint the facade walls at minus temperatures, it is better to choose a special winter paint.

Also, before you start painting, you should remove the old layer of paint, clean the walls from dust, sand them and apply a layer of primer. The latter perfectly prepares the walls for further painting.

Considering the characteristics of facade paint selection, it becomes clear that the best composition for exterior wall design is the one that is most compatible with the surface material, resistant to local atmospheric and natural phenomena, less toxic, has decorative appeal and pleasant texture.