- Error one – wrong temperature conditions
- The second mistake – refusal of the primer
- Mistake three – speed up the drying process
- Mistake four – incorrect mixing
- Mistake five – too thick layer of plaster
Plastering the walls with your own hands is not so difficult. However, if you do not adhere to the basic rules, you can get not only an uneven surface, but also cracks, peeling pieces of plaster, bulges and other problems..
First, we will give advice – choose the right plaster mix, do not save. Do not use gypsum mixtures in damp rooms or on concrete surfaces. It is also impossible to plaster with lime mortar on gypsum. Follow the manufacturer’s instructions and recommendations, which should indicate which surface is best used for this plaster.
We have selected the most typical, most gross and threatening mistakes that many non-professionals make when plastering walls..
Error one – wrong temperature conditions
Experts recommend working with plaster at temperatures from + 5 ° C to + 25 ° C. If the room is too cold, the plaster will harden much more slowly, its strength characteristics will decrease. In the summer heat and with too active heating of the room, part of the water from the plaster mixture will evaporate. It will result in too fast drying effect, violation of technology and, as a result, problems.
We advise you, if renovation work is carried out in the summer, to curtain the windows. It is impossible for direct sunlight to fall on the newly plastered walls.
The second mistake – refusal of the primer
Poor adhesion, adhesion to the surface, can lead to the fact that the plaster simply falls off, peels off the wall. There are surfaces that absorb moisture well: ceramic foam blocks, silicate and ceramic bricks, aerated concrete. There are surfaces that absorb little or no moisture: expanded polystyrene, concrete. For each type of surface, you should choose your own primer, which is carefully applied to the entire wall.
Important! The drying time of the primer can be up to 24 hours. Be sure to study the manufacturer’s recommendations and do not start plastering earlier than the specified time, only after the primer has completely dried.
Important! Replacing a special primer by wetting the wall with ordinary water does not significantly increase adhesion.
Mistake three – speed up the drying process
You cannot use a construction hair dryer to dry the plastered surface in the shortest possible time. It is impossible to specially warm the room by installing near the wall, for example, an oil heater or a convector. Do not hurry! No draft is needed, but natural ventilation is necessary. In such conditions, the plaster will dry gradually and correctly, without cracks..
Mistake four – incorrect mixing
To be precise, two mistakes can be made here:
- Add water to the mixture. The opposite is necessary! If you pour water into a dry mixture poured into a container, lumps will definitely appear, which will be very difficult to break. It is much better to gradually pour the dry solution into the right amount of water, stirring thoroughly all the time;
- Add dry mortar to the mixture, trying to get the right amount and finish plastering one of the walls. Kneaded – used and kneaded again.
Mistake five – too thick layer of plaster
We understand that we want to do all the work as soon as possible. But rushing won’t help! Do not apply too strong a layer of plaster at once. When spraying a wall with the composition, the layer thickness should not exceed five to nine millimeters. Spraying the wall helps to fill in all cracks and irregularities with plaster. When the first layer has set, the next one is applied, already to level the surface. Maximum thickness of one layer – 3 cm!
Be sure to wait until the plaster dries to continue working, even if you have to skip a whole week. Eventually, during this time, you can do other rooms or other types of renovation work..