Is it possible to putty foam and other non-standard materials
Those who build or repair their own homes with their own hands often have difficulties associated with a lack of knowledge and experience in this area, for example, everyone knows that concrete, brick and block walls can and should be plastered and putty for subsequent finishing.
And if they are made of OSB, wood and other non-standard materials? Is it possible to align them in a similar way?
The content of the article
What should be the surface for putty
It is possible to rely on the fact that the plaster or putty will lie on the surface and will adhere well to it under the following conditions:
- The leveling mixture must match the type of material to be coated. For example, there are special wood putties (seeHow to putty wood: materials, tools, process technology), metal, silicate substrates, as well as universal mixtures suitable for finishing a wide variety of materials.
Note. Putty must also be appropriate for the place of application - for indoor or outdoor use.
- Instructions for puttying surfaces require that they be porous, rough. Most compounds do not lie on a perfectly smooth, glossy base.
Or adhesion to the surface is not strong enough, as a result of which the putty quickly crumbles. Therefore, such bases are preliminarily prepared by coating with a special primer (seeTypes of construction primers and their scope) or artificially roughening them. - The surface must be strong and stable - not crumble, not crumble and not delaminate. The same applies to the coating previously applied to it: if it does not adhere well, it is completely cleaned before puttying.
- Rigidity is one of the requirements for the trimmed plane. It is clear that soft and flexible materials are deformed during mechanical action, which will cause instant putty detachment. But the necessary stiffness can be created using a reinforcing mesh and a sufficiently thick leveling layer.
Based on these basic requirements, let's consider the possibility of applying putty on some materials that can be considered problematic. Is it worth it?
Will the price of materials and the cost of work pay off for many years of trouble-free operation of putty-finished surfaces?
How to putty unusual bases
Consider the main types of surfaces that may need to level with plaster or putty mixtures. They are found both during the decoration of new buildings and in the process of repairing old buildings.
Fiberboard, particleboard, hardboard and other wood-like materials
Often they make internal partitions or sheathe walls, ceilings. If subsequently they are planned to be wallpapered or painted, then the alignment and sealing of the seams between the sheets is necessary.
Can fiberboard and other materials based on woodworking waste be putty? Yes, but taking into account the natural ability of a tree to absorb moisture and deform during swelling and drying.
What does it mean? That before finishing it is necessary to reduce the absorbent capacity of the material by coating it with a primer based on water-insoluble acrylic resins.
The process itself does not differ from plasterboard putty or plastered walls:
- The first stage is dust removal of the surface and priming.
- The second stage is directly putty. First, the joints between the sheets, then the entire plane.
- The third stage is grinding after drying, re-priming and finish finish.
Tip. For such surfaces that are characterized by good adhesion and the absence of large defects, finishing polymer or gypsum putties are recommended.
OSB
This new building material, made of wood chips and resin, has been actively used recently for the construction of frame houses. It is also the basis of SIP panels, in which a layer of insulation is glued between the sheets of the OSB.
The external and internal structures formed by him need decorative decoration, since not everyone likes the appearance of the material. But is it possible to putty OSB? After all, its surface, filled with a binder, is very smooth, it will not allow the leveling compound to firmly adhere to the base.
It is possible, but also in compliance with special technology, one of the stages of which is surface preparation. Its goal is to give the material a roughness and better adhesive properties.
It is done like this:
- The plane is treated with abrasives, stripping the top layer and making the plates rough;
- The surface is dust free;
- A deep penetration primer is applied to it.
Tip. It is advisable to use a primer with a filler in the form of fine-grained mineral particles (silica sand, for example). It will simultaneously strengthen the base and give it additional roughness for better adhesion to the putty.
As in the previous case, acrylic or gypsum compositions are recommended for finishing OSB.
Heaters - polystyrene foam, polystyrene foam, polyurethane foam
In our climatic conditions, building insulation with special materials is a common thing. But what about after the completion of these works? Is it possible to putty on the mounting foam, which filled the cracks in the window and doorways? Or foam boards glued to the walls?
Of course, yes, since these materials have both the necessary porosity for adhesion to leveling mixtures and the strength of the surface. And insufficient rigidity is corrected using reinforcing materials and an increase in the thickness of the putty layer.
The fiberglass mesh is glued to the foam using conventional cementitious adhesives. After drying, the surface is ground and leveled. finishing putty.
And for finishing areas treated with polyurethane foam, it is cut with a sharp knife to a shallow depth from the plane, the resulting cavity is filled first with a rough leveling compound, and then with the finish. Or, after rough leveling, a continuous putty of the surface is carried out.
Clay bases
Old buildings were often “smeared” - trimmed with clay mortar on shingles. These are thin wooden battens packed on walls, which serve as reinforcement for mortar.
Unfortunately, no putty, even if pre-primed, will not hold well on such a surface, so this time to the question: can it be putty on clay, we will answer negatively.
What to do in this case:
- If the surface is relatively smooth, with only small defects in the form of cracks and small potholes, it can be cleaned from falling off and exfoliating pieces and re-leveled with the same clay. And then cover with whitewash, water-based paint or wallpaper.
- Shabby crumbling surfaces should be completely cleaned of clay, then plastered or putty with compositions that correspond to the type of base material.
- Fasten the steel reinforcing mesh to the walls, plaster and putty it.
Tip. All these methods are very laborious and do not guarantee an excellent result. The easiest way is to wall the walls on the frame with sheet materials, and already align them using standard technology.
Paint, whitewashing
Old buildings often cannot boast of the perfect finish: a couple of decades ago, builders did not bother to draw level planes, painted walls and whitewashed ceilings directly on plaster. If you have to correct such defects, then you need to know whether it is possible to putty on whitewash or paint.
This depends on how firmly the coating adheres to the substrate, as well as its physical properties.
Let us explain:
- Cretaceous and calcareous whitewash, as well as a completely modern emulsion or water dispersion paint, swell from exposure to water. This means that when applied to whitewashed or painted putty surfaces, these coatings will absorb moisture from the solution.
Of course, the quality of such a finish is out of the question - it will fall off already in the process of drying. Therefore, whitewashing must be scraped off with a spatula, after soaking it with warm water. After that, the surface is dried and primed as usual.
- Oil and enamel coatings can be puttied if they adhere well to the walls, but they need to be roughened. If the paint is cracked, exfoliates or crumbles, it is cleaned.
Conclusion
As you can see, even some non-standard materials can be puttied if you know how to do it correctly. If you still have questions, check out the video in this article for their resolution.
