How to check the quality of plaster work. High-quality plaster: designation of the concept, applicable standards and control of work

• Simple up to 12 mm.
• Improved to 15 mm.
• High quality up to 20 mm.

Requirements for the quality of various types of plaster.

On flat brick surfaces plaster thickness can be up to 10 mm, and on new concrete surfaces up to 2 - 3 mm, i.e. covering with grout. On surfaces made of straw, reeds and fiberboard, the thickness of the plaster should not exceed 20 mm without additional preparation. On wooden surfaces it is desirable to install a layer of plaster with a thickness of 20 mm or at least 15 mm from the level of the output peel, since thinner layers of the solution are easily torn from warping of stuffed panes, and the peel itself is “imprinted” on the surface of the plaster.

The plaster must adhere firmly to the surface, not peel off; have a well-worn surface, without external defects. The accuracy of the plaster being performed is checked with a rule (rake) 2 m long. different directions: vertical, horizontal, diagonal. If the deviations are greater than the norms given in Table. 1, they are eliminated (the solution is cut off or additionally applied).

The verticality and horizontality of a simple plaster is controlled by a rule or a cord, i.e., pulling the cord with an indent on the thickness of the plaster and arranging marks and beacons under this cord. For improved and high-quality plaster, the surfaces are hung, stamps and beacons are arranged.

The quality of the plaster

Uch.posoble Plastering. Shepelev.A.M.

1. To test the wet and dry strength of old plaster, rub it with a wire brush.

2. To test the hardness of the old coating, run the flat side of the screwdriver across the surface while applying firm pressure to the screwdriver.

3. If the surface remains deep scratches then the old plaster must be removed.

How to determine the presence of voids under the old plaster coating?

4. The entire surface should be carefully checked, especially in places of cracks.

5. Tap the surface with a hammer or a metal rod; in places of voids, the sound will be muffled.

6. In places of voids, beat off the old plaster

How to determine the type of old plaster coating? How to determine what the walls are plastered with?

7. In order to understand whether the old coating is compatible with the new, it is necessary to determine its nature - mineral or polymer.

8. Under the action of the flame: (for example, blowtorch) polymer coatings soften or crack, and polymer binders emit a specific odor.

9. Mineral plasters (lime-cement, cement) do not react to the flame.

How to check the adhesion strength of polymer plaster or paint?

10. If the old coating (plaster or paint) is not to be removed, it is necessary to check the strength of its adhesion to the base.

12. The adhesion strength of paints or polymer plasters with a rough surface can be checked with a spatula or knife.

11. On a 10x10 cm area, apply horizontal and vertical scratches in 2 mm increments. If >80% of the paint is retained, the adhesive strength is considered sufficient.

How to find out the adhesion strength of new plaster with the old coating (paint or plaster)?

When the surface is covered polymer paint or plaster, you need to know what the strength of their adhesion to the new plaster.

13. Cement-lime plaster may not have sufficient adhesion to polymer plaster or paint (saponification).

14. Apply a plaster layer on the surface of the old coating and sink a 50x50 cm grid into it so that the edge of the grid is not covered with mortar. Let dry for 3-4 days.

15. If the solution remains on the surface when the mesh is torn off, the adhesive strength is sufficient. If a fresh mortar or an old coating is removed together with the mesh, then the adhesion is fragile, the old coating must be removed.

How to determine the absorbency of a substrate?

16. This must be done to determine:
. what primer should be used.
. whether it is necessary to use a special solution with increased adhesion.

17. Moisten the base with bottled water.
1) Water is quickly absorbed, the stain increases rapidly. Treat the base with a primer at least 2 times.
2) water is absorbed, the stain slowly increases. Treat the base with a primer.

18.

3) water, slightly absorbed, wets the surface. It is necessary to treat the base with a primer.
4) water flows freely from the surface without wetting it. It is necessary to treat the base with a primer.

Articles similar to How to check the bearing capacity of old plaster?:

Plastering is very milestone finishing works, on which the comfort and beauty in your home most directly depend. In order for the living room and bedroom to always please the eye, it is necessary to give Special attention choice and plaster, and builders who will carry out the decoration of the premises. In this article, we will focus on what requirements building mixtures must meet and how to check the quality of the work performed.

To begin with, a few words about the quality characteristics of the plaster. It protects the surface from various scratches, bumps, chips and other mechanical damage. To solve the assigned tasks, decorative coatings and must have good adhesion (strong adhesion to the surface) and water resistance. Adhesion prevents the material from shedding during operation, and water resistance helps to avoid serious problems in case of flooding of the apartment. Among other things, high-quality is elastic. It is no secret that the constant movement of the soil causes small deformations of the supporting structures. If you decide to save money and buy cheap Decoration Materials don't be surprised if they start to crack after a few years.

Now about the requirements for applying plaster. how to put it on the walls, you need to premise and prepare the surface. The old ones for the walls are removed, as, indeed, the old plaster. After that, all surfaces are thoroughly cleaned of dust, stains of various origins and other contaminants.

The solution is applied evenly over the entire wall, the layer should not exceed 20 mm. The check begins with an inspection of the corners. By how carefully the joints are made, you will immediately understand whether it is worth waiting for unpleasant surprises. Next, inspect the main surface of the walls. It should be flat and smooth with clearly visible edges at the corners. Any mounds, cracks and potholes are the basis for claims to the builders.

To check the strength of the joints, apply a few blows to the plaster in randomly selected places. Of course, the quality does not allow any delamination. The sound upon impact should be deaf, which indicates the absence of voids and the uniformity of the application of the finishing layer.

The evenness of the walls should also be checked. To do this, take a rule at least 2 meters long and attach it to the plastered surface. If the finishing was carried out by professionals, then the size of the gap does not exceed 5 mm. The verticality of the walls is checked using a plumb line. The quality criterion is the same - the gap should not be more than 5 mm per 2.5 m of the surface.

How to check the evenness of the wall with a laser level - laserpribor

Linear laser level projects a laser line onto the wall. In this case, a laser plane appears between the wall and the laser level (horizontal or vertical, depending on the model of the level).

A vertical plane is used to check the evenness of the wall!

There are two methods for assessing the flatness of a wall (checking for depressions and bumps on the wall surface):

1. Checking evenness over a large area of ​​the wall.

2.Check for evenness in a small area.

The method for checking evenness is based on the projection of the beam at a certain angle to the wall and mathematical calculations.

1. Checking evenness over a large area of ​​the wall.

This technique is useful in estimating the volume plastering works, but can also be used when checking at the end of plastering and painting work. As a rule, before plastering, the differences along the wall are quite large and they are already noticeable - this technique will allow you to quantify the amount of work to level the wall with plaster.

Must be enabled vertical plane laser line leveler (plane builder), set the level at the edge of the wall so that the vertical laser plane runs parallel to the wall. This requires marks on the floor along the wall at the same distance from wall A and B, as shown in the figure:

In this case, the builder builds a plane parallel to the planned surface of the plastered wall (not the plastered surface itself, but the plane parallel to it). If a wall section without a laser beam appears on the opposite wall from the level, then the beam is interrupted in some place by the convex part of the wall - you need to move the laser level away from the wall and make new marks A and B.

To check the differences on the wall surface in one vertical section (from to the ceiling), you need to take a steel or wooden meter with a millimeter scale without moving parts (a tape measure will not work precisely because of the movable hook that almost every tape measure is equipped with).

We select a vertical section of 1-2 cm and put the meter perpendicular to the wall - the free end of the meter rests against the wall at an angle of 90 degrees to the wall surface, and laser ray will appear on the tape measure plane showing the distance from the base laser plane to the wall (size 1). Then we rearrange the meter lower on the same vertical line and get a new distance (size 2). We take as many measurements as needed.

Now the data for this vertical segment can be compared with the data for the vertical segment of the wall in 40 cm or in a meter.

We compare the obtained dimensions and get an idea of ​​the curvature of the wall relative to our base vertical in centimeters and millimeters.

2. Check for evenness in a small area.

When the wall is plastered and the preparation of the wall for gluing or painting is completed, the irregularities, as a rule, are 1.2.3 mm and it is not always convenient to search for them using the first method with a ruler.

Particularly visible are the irregularities on the walls for painting, painted dark and on which straight lines fall. Sun rays at an angle... The same method is used when evaluating the evenness of the wall after finishing before painting and wallpapering.

This technique is not difficult to apply. First, we need to visually mark a square on the floor near the wall that we will measure (or draw it with chalk or mark it with some objects) - we need it in order to then put the builder under right angle to Wall. We mark points A (the laser plane is perpendicular to the wall), B (the laser plane is at an angle of 45 degrees to the wall), then we mark points C, D, E by dividing the segment between the wall and the previous marked point in half (we get angles 45/2 = 22, 5; 22.5/2 = 11.25; 11.25/2 = 5.62):

At the same time, when a plane falls on a wall, it will be flat at any angle only when the wall is perfectly flat! With unevenness, the beam will bend, and the smaller the angle (the sharper it is), the greater the curvature!

In places of unevenness, the beam will bend relative to the center of the measured area - if it bends away from the builder (point A1), then in this place we have a hole on the wall, if it bends towards the builder (point A2), then there is a bulge on the wall. Let's clearly demonstrate this in Figure 5:

If a horizontal beam is directed at the wall at an angle (it is necessary to tilt the builder relative to the horizontal plane in this case), then it will show the unevenness on the wall from left to right (horizontal curvature), and not from top to bottom (vertical curvature).

How in millimeters is the dip or bulge X? Everything is very simple! You must use the trigonometric formula from the high school course! The cotangent will help us - the ratio of the leg adjacent to the corner (just the distance A1) to the opposite leg (the desired value - unevenness X).

When the angle of incidence of the beam on the wall changes, the ratio of A1 to the desired value X will change. The sharper (smaller) the angle of incidence on the wall, the greater the value of A1 or A2, the greater the coefficient:

A1 / ctg "angle of incidence of the beam on the wall" = X

Here are the values ​​of the cotangent of the angles that we used in the calculations:

And this is an example of calculating the roughness in millimeters, depending on the angle at which the beam falls on the wall:

Source: www.laserpribor.ru

How to check plaster?

Instruction

.1

Before deciding whether the plaster needs to be replaced or not, it is necessary to check its strength, how well it adheres to the wall. Based on the results obtained, mono will draw the appropriate conclusion: it is necessary to re-plaster the wall, leave it in the state in which it is currently or a small one will be enough cosmetic repairs in some areas.

.2

The easiest way to check the plaster is to use a scraper or spatula. It is necessary to take the appropriate tool and run it over the surface, in those places where the cement crumb begins to crumble, it is necessary to carry out cosmetic work. The easiest way to check the plaster is to remove the wallpaper from it, if any. If it begins to collapse along with them, then such a coating is no longer subject to partial correction and requires a complete replacement.

.3

To determine the strength of a plastered surface, you can take a simple hammer and tap its handle on the surface. In places where the coating is not securely held, a dull response will be heard, they need to be marked with something. If there are many such places, it is recommended to completely re-plaster the wall.

.4

You can also dry the surface and see if there are damp places on it. As a rule, they will differ in characteristic color shade, it will be darker. In this case, it is necessary to re-plaster not only the damp area, but also around it by 50-70 centimeters.

.5

If at first glance the quality of the plaster is unsatisfactory, it is not recommended to save money, but to take and replace the entire coating. Grease stains can appear on the plaster, the cause of which often lies much deeper - in the wall itself. In this case, it is recommended to make a chip on the wall and apply a new solution.

.6

It is recommended to check the presence of cracks in the plaster with a small sharp object. Without pressing hard, they need to run through all sections of the wall, when a crack appears, the object will jump or, on the contrary, fall into it. Then the crack needs to be enlarged on its own and covered with fresh mortar. It is worth noting that all work is carried out on dry plaster, so it must first be dried.

Plastering walls - a question about the quality of work - a discussion on the forum ngs.dom in novosibirsk

Next, you need to understand what quality you agreed on. And guided by the following excerpt from SNiP, you can accept work. With a good apartment renovation, as a rule, it is considered as high-quality (I will give notes in parentheses on its example) or, at worst, improved.

Plastered surfaces

Measuring, at least 5 measurements with a control two-meter rail on 50-70 m2 of surface or on a separate section of a smaller area in places identified by a continuous visual inspection (for molded ones - at least 5 by 35-40 m and three per element), work log

vertical deviations (mm per 1 m), mm:

with simple plaster - 3

No more than 15 mm to the height of the room

the same, improved - 2

The same, no more than 10 mm

the same, high-quality - 1 (attach a 2m level to the wall vertically, with this measurement, the deviation of the wall level by the length of the rule should not exceed 2mm)

The same, no more than 5 mm

irregularities of a smooth outline (per 4 m2):

with simple plaster - no more than 3, depth (height) up to 5 mm

the same, improved - no more than 2, depth (height) up to 3 mm

the same, high-quality - no more than 2, depth (height) up to 2 mm (attach the rule arbitrarily in all planes, the gaps under the rule, or vice versa, smooth bulges should not exceed 2 mm)

horizontal deviations (mm per 1 m) should not exceed, mm:

with simple plaster - 3

the same, improved - 2

same, high quality - 1

Another important point... Selectively tap the walls with a metal object, such as a door key. In places where the plaster has poor adhesion to the base, you will not hear a thud as it should be, but a feeling of emptiness. You can safely say that such places should be opened and redone at your own expense, this is a clear negligence in work. The same can be said if under the rule there is a hole as thick as a finger. or vice versa, a bump, well, all the norms for these deviations are listed above.

Plaster can be simple, improved and high quality. Contrary to popular belief, these definitions do not refer to the quality of the material, but to the technology of work and finishing characteristics, which are regulated by the requirements and rules of SNiP and GOST. Consider the differences between improved plaster and other types of plaster finishes and the requirements that it must meet.

Differences between different types of plaster

Tolerances for improved plaster

In accordance with SNiP 3.04.01-87, plastered surfaces may have deviations that are not a violation of the norm:

• from the vertical and horizontal, the coating may have a deviation of no more than 2 mm per 1 m of length;
• for the entire height of the wall, the surface can be deflected by no more than 10 mm;
• slopes of windows and doors, pillars, pilasters, husks can be deviated by no more than 2 mm from the vertical and horizontal per 1 m of length;
• the radius of curved surfaces can be deviated by 7mm from the value specified in the project (control is carried out using a pattern);
• the width of the slope may differ from the design by 3 mm.

Important! SNiP for improved plaster does not allow the presence of delaminations, cracks, shells, efflorescence on the surface, as well as visible traces of the tool that was used for grouting.

Requirements for the quality of the used plaster compositions

The quality control of the used material and mortar is carried out on the basis of GOST 28013-98 “Construction mortars. General technical conditions".

According to GOST, the solution for improved plaster must meet the following requirements:

1. The solution intended for spraying and soil must pass through a mesh with a mesh diameter of 3 mm.
2. The solution for the coating layer must pass through the mesh, which has a mesh size of 1.5 mm.
3. The sand used to prepare the mortar must contain grains, the size of which does not exceed 2.5 mm in mortars for soil and spray and 1.25 mm for finishing.
4. GOST also regulates such technical specifications such as mobility, exfoliation, water retention and strength.

An additional requirement of GOST is the presence of a document in the solution, which indicates:

• date and time of preparation;
• brand of solution;
• quantity;
• mobility;
• binder component;
• standard.

Quality control of plaster works

Control over compliance with the requirements of SNiP and GOST is carried out at three stages: at the stage of preparation, in the process of work and at the stage of inspection and acceptance of the finished base.

For control on preparatory stage necessary:

• check the quality of the solution;
• determine the humidity of the walls and temperature;
• make sure the walls are cleaned of dirt.

In the process of performing plastering works, control of verticality and horizontality, as well as the quality of the resulting coatings, is carried out.

On last step control consists in checking the adhesion strength of the dried mortar with the wall and the quality of the surface that has undergone sanding.

There are three types of plastering works, which are distinguished by quality. This must be remembered when concluding a contract for the repair of an apartment. In addition, when checking the quality of plastering work, it must be remembered that the rule must not be applied to the working surface.
According to the quality, plastering works are divided into simple, improved, high-quality plastering works.
All deviations are checked using a 2 meter long rule.

Simple plaster - applied in basements, warehouses, non-residential premises, attic premises, in all premises where a perfectly flat surface is not required.
Apply by spraying, in two layers, do not hang, do not apply a covering layer, rub the resulting surface. Thickness is usually 10-12 mm. Permissible deviations at ordinary plaster– no more than three irregularities up to 5 mm deep or high when the rule is applied. Deviation from the vertical is not more than 15 mm for the height of the room, from the horizontal is not more than 15 mm for the entire room. Deviations of the width of the plastered slope from the design one with this plastering are not checked.
Such a view as improved plaster is carried out in public and residential buildings, in utility rooms. Perform improved plaster as follows - throw a layer of spray, a layer of soil, a covering layer with a rule check. The average layer thickness is 15 mm. At the end, the covering layer is rubbed with graters and smoothed with trowels.
With improved plaster, the following deviations are permissible - no more than two irregularities up to 3 mm. Deviation from the vertical, no more than 2 mm per 1 m of height, but not more than 10 mm for the entire height of the room, deviation from the horizontal - no more than 2 mm per 1 m of length, but not more than 10 mm for the entire length of the room limited by girders, beams, etc. P
High-quality plastering work is carried out in those buildings and structures, the finishing of which is subject to increased requirements, hotels, residential premises, public places. Such plaster is carried out by installing beacons and spraying, and then pulling along the beacons. Moreover, beacons can serve various materials, it can be both galvanized beacons, and beacons can be made from quick-hardening solutions (alabaster).
The requirements for high-quality plaster are as follows, no more than one unevenness with a depth or height of 2 mm, when applying the rule. Deviation from the horizontal is 1 mm per meter of length but not more than 7 mm for the entire length of the room, deviations from the vertical can be 1 mm per meter of height but not more than 5 mm for the entire height of the room.
Depending on what kind of plaster is being performed, they can also change during repairs.
Therefore, starting the repair of an apartment, or even a small one in an apartment, specify what kind of plaster you will use.

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