Gypsum putties are widely used in construction and renovation activities. Before we discuss them specifically, it is appropriate to clarify what gypsum is and what putty is.
Gypsum is a mineral building material. It is perceived by many as a product of modern times, but in fact it has been used in construction since ancient times. Finishing materials based on it are traditionally present in the plastering and covering of facades, walls and ceilings, creating an ecological "breathing" environment. Decorative gypsum elements complete the appearance of facades and interiors, giving them a palette of qualities - from opulence to classical sophistication. Modern buildings also rely on gypsum products for the construction of structural elements such as partition walls, suspended ceilings and raised floors.
HOW IS PLASTER MADE?
Gypsum products are widely used in the plastic arts, medicine and construction, but do we know where the white material comes from? In nature, gypsum is a crystalline mineral that is formed from sedimentary rocks when water evaporates in closed sea lagoons. Its natural color is not necessarily white, but varies from pink to brown, yellow and gray. White construction gypsum is obtained by heating the natural mineral to temperatures of about 150°C, which evaporates over 75% of the water contained in it. Subsequently, the resulting material is ground into powder, which is the starting material for many products based on it. Gypsum is vapor-permeable and regulates humidity in rooms, has no odor and is completely harmless. These qualities make it an environmentally friendly material, an excellent choice for creating a healthy living environment.
GYPSUM HAS BEEN USED AS A BUILDING MATERIAL SINCE THE TIME OF THE
Mixed with water, the mineral was used as a building material as early as 9,000 years ago in Asia Minor and Syria. Gypsum plasters were then used to cover walls and fill cracks, and gypsum mortar served as a binding material for brick masonry. 5,000 years ago, the Egyptians used it in the construction of majestic monuments such as the Cheops Pyramid to seal the laid stone blocks. In ancient cultures, gypsum powder was mixed with water, sand and animal fur and the resulting mixture was used to plaster hedge walls - similar to the mud-plastered hedges of old Bulgarian houses. The ancient Greeks also used gypsum, sculpting translucent "glasses" for their temples.
During the late Renaissance, plaster of Paris gained popularity, as after the Great Fire of London in 1666, the Sun King Louis IV ordered all wooden houses in France to be plastered with plaster - a material with very good fire resistance. The execution of the order was facilitated by the huge deposits of the mineral in Montmartre, near Paris. At that time, as well as later in the Baroque and Classicism, plaster decorative elements were widely used for interior and exterior decoration, most often painted in luxurious gold.
APPLICATION OF GYPSUM
The applications of gypsum materials and products today are similar to those of previous centuries and eras, with their technical characteristics being improved mainly. In general, we can divide them into two groups. The first consists of various binding and finishing mixtures for plasters, putties and adhesives, and the second - of final products such as various gypsum boards, gypsum fiber boards, gypsum-coated bricks, gypsum blocks and decorative elements.
The most common applications of gypsum mixtures are for the production of various types of plasters, putties, as well as for gypsum adhesives, which are preferred in construction with gypsum elements.
WHEN IS PUTTY APPLIED?
Today, there are modern materials for making masonry, walls and better quality formwork. Thick lime plasters are increasingly used at the expense of thin-layer decorative plasters. Modern plastering materials make the work so much easier, and among other things, the plaster made in this way is of high quality. This is additionally guaranteed by the reliability of the materials. Among the main advantages of the new materials is the simplified preparation of the solution. It is guaranteed to obtain a solution that has optimal qualities for applying the plaster.
Putty is the last finishing coat before painting. It aims to straighten even the smallest curves on the walls. The thickness of the putty should not exceed 10 mm.
Putties are designed to achieve geometrically straight and perfectly smooth walls and ceilings. Depending on their composition, they can be used in dry or damp rooms.
Puttying is almost always necessary if the wall is to be painted or wallpapered. The adhesion of wallpaper to a smooth and sanded surface is better, and the bond between the base, glue and wallpaper is stronger. The absorbency of a putty wall is even and the wallpaper sticks well. If the wall is not puttyed and especially if the wallpaper is thin, the roughness and stains on the base will show through. When the surface of the walls is of good quality or the wallpaper is dense, thick and embossed, puttying may not be necessary.
TYPES OF PUTTY
Putties are dry mixtures, diluted in water or ready-to-use paste-like substances. There are two types of putties - leveling and finishing. Leveling is intended for preliminary leveling of the surface and filling of larger cracks and holes.
Most often, dry putties are based on gypsum or cement, modified with polymers and various chemical additives. They increase their adhesion properties (the adhesion between particles), guarantee uniform drying and elasticity of the entire layer.
HOW IS THE PUTTING MIXTURE PREPARED?
The putty mixture is gradually poured into a pre-measured amount of cold water and mixed using an electric mixer until a homogeneous mixture is obtained. It is left to mature for 10 minutes and mixed again. It is recommended to mix at a speed between 400 and 800 revolutions per minute, so as not to introduce air into the mixture. The consistency of the mixture is taken into account in the specific conditions, but it is mandatory that it be the same for the entire work site.
The thickness of the first layer to be applied should not exceed 10 mm. The layer should be elastic. This helps to prevent the surface from shrinking and cracking after drying. The next layer of finishing putty is no more than 1-2 mm. The total thickness of the two layers should not be greater than that allowed for a given brand of putty. Preparation for application, as well as the characteristics of the types of putty, are described in the instructions of each manufacturer. After preparing the mixture, different putties are suitable for application in different periods of time (open time). With a longer open time, premature drying does not occur. There is enough time for work, there is no need to prepare new portions frequently and the material consumption is reduced.
WHAT TOOLS ARE NEEDED FOR PUTTING?
For a smooth and quick application of putty, it is recommended to use a stainless steel trowel and spatula. To level the inner corners, a special trowel with two perpendicular planes is used. The outer corners are formed by applying putty first on one side, and then making a final leveling on the other side with a regular trowel.
HOW IS PUTTY MADE?
Putty is applied in an even and thin layer to the base. It is necessary before the final coating, whether it is paint or wallpaper.
It starts with priming - a preparatory operation that ensures the uniformity of the base and facilitates the application of the next coating. The synthetic resins contained in the primer strengthen the bonds between the individual particles and thus strengthen the base. The applied layer with a putty knife or a putty knife forms a fine coating that reduces the absorbency of the base. After the primer has dried, which takes about 4-6 hours, you can proceed to applying the first layer of putty.
There are also certain requirements when mixing dry building mixtures. Depending on their type and purpose, they are mixed at slower or faster speeds. When the mixture is mixed slowly, air is not introduced into the material, and so when it is applied to the base for which it is intended, it is smooth and easy to work with. A very important condition for achieving a good final result is also the maturation of the mixture. After initially mixing with water, some of the ingredients of dry building mixtures are not activated immediately. They need some time to remain under the influence of water and air. This time is different for different products and manufacturers strictly mark it on the packaging. In order for the mixture to reach its best performance, it must be mixed again. Only then can the actual work begin - applying the mixture to the surface. With a putty knife or trowel, material is placed on one end of the trowel. With light pressure, starting from the bottom up, the material is spread. This can be done more than once. Once enough material has been applied, the plastering process begins. The trowel is cleaned with the putty so that no material remains on it. Then, with circular movements at an angle of 30° in one direction only, the wall is smoothed. After the first leveling layer of the putty has dried, all irregularities on the wall are leveled and sanded with sandpaper.
Brush off the dust from the wall to ensure better adhesion between the two layers and then apply the second finishing layer. For the final plastering, a new plaster is used. It is designed for smoothing the surfaces of walls and ceilings indoors. The maximum layer thickness is 2 mm. And when mixing this mixture, the same rules apply as for the previous plaster – mix at slow speed and wait about 5 minutes.
HOW LONG CAN THE MIXTURE BE USED?
When storing the mixture in a well-closed container, it can be used for 24 hours. The ingredients of the mixture suggest a slightly longer drying time – about 24 hours per 1 mm layer. Naturally, the drying time depends extremely on the temperature and humidity of the environment. It is recommended that when starting to plaster, the temperature be above 10 degrees. This is important, since drywall allows work in winter, but when plastering, the temperature must be monitored. Otherwise, there is a risk that the joint will crack over time.
WITH GYPSUM PUTTY THE WALLS "BREATHE"
Plastering with gypsum products is used as a finer finishing layer on internal lime-cement plasters, concrete walls, panels, plasterboard, gypsum fibreboard and gypsum blocks. The base for application must be stable, dry and even. In the case of very porous materials or older plasters, preliminary application of a primer is mandatory. Gypsum putties are used for fine leveling of the surfaces of rooms by filling in scratches and joints. They allow the structure to “breathe” and create a base that is smooth enough for applying paints and wallpapers.
Modern putty mixtures provide an open working time of about one hour, which allows mixing larger quantities for larger areas. The high quality, elasticity and plasticity make the putty areas very easy to further process.
The general rule when applying putty, as with plaster, is to start from the ceiling, so as not to spoil the appearance of the already putty walls. Usually, one coat is applied with a mixture in a ratio of gypsum to water 1:1 and the second - with a finer mixture in a ratio of 1:2, which fills even the finest irregularities.
WHAT DO WE OFFER?
With us you can find gypsum putties of both types - leveling and finishing. There are also differences in the sizes, which are 15 and 20 kg. The putties are suitable for smoothing surfaces and bases with different coatings, which are reflected in their personal technical cards.
The products in this group are from the brands WEBER, KNAUF, BORO, CERESIT, BAUMIT, TERAZID.
The prices are affordable.
