The final stage of the process of installing modern windows is finishing the slopes. A thick profile, multi-chamber double-glazed windows and reliable fittings provide excellent thermal insulation, but the interface between the window frame and the apartment wall remains a cold and unattractive place. If this area is not given proper attention, condensation, mold, and wall destruction may occur. Therefore, let's find out which slopes are best suited for plastic windows.
What requirements must slopes meet?
Before considering window framing options, their advantages and disadvantages, let’s determine what is required of these elements.
Expert opinion
Anton Tsugunov
Construction expert. Entrepreneur. 17 years of experience. More than 100 completed objects.
Hello, friends!
First, I will talk about all types of slopes, as well as their pros and cons. I will describe the subtleties and share my experience. At the end of the article I will give recommendations on which slopes are the best choice, and in which cases one should give preference to one or another material and finishing method.
Important!
When applying for a slope installation service, be sure to enter into an agreement with electronic correspondence , then you can resolve all issues with the builders promptly and without headaches. Here is a link to my contract >>>
If you have problems with the quality of the slopes or with the timing of their installation, then you will need to write a claim. Here are samples of claims by deadline >>>
Enjoy reading!
Slopes should:
- Not inferior to the durability of the window design. Modern double-glazed windows are designed for a minimum of 15–20 years of operation. Slopes must withstand no less time without loss of basic qualities. Few people would like to redo them every two or three years.
- Comply with the general style of the window, forming a single whole with it.
- Maintain or even improve the performance characteristics of plastic windows.
- Withstand mechanical loads and impacts of the doors.
- If possible, be repairable.
Stucco molding
Internal slopes can be so self-sufficient and attractive that there is no need for a curtain. Decorate them with an unusual pattern or stucco frame to turn them into the main design accent of the interior.
Additionally, play with the rich stucco pattern in ceiling skirting boards, window cornices or door frames.
Slope finishing options
When renovating an apartment in a new building or replacing windows, you will have to choose how to finish the openings after installing modern structures with double-glazed windows.
Window slopes can be finished using the following materials:
- plaster;
- drywall (gypsum plasterboard);
- gypsum fiber (GVL);
- plastic panels.
We recommend
Open type roller blinds.
Attaches directly to the frame, no drilling required.
Excellent protection from the sun and heat.
They don't take up space.
Many colors and sizes.
Price from 600 rubles for a complete set. Delivery is free from 3 days.
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Sandwich panels
You can install slopes on plastic windows using sandwich panels yourself in the same way as described above.
Installation diagram of sandwich panels on a slope
The photo shows a method for attaching sandwich panels without a starting profile. With this method, a 1 cm deep slot is made in the assembly seam into which the panel is inserted. From the outside it is attached to the leveling profile.
Advantages of sandwich panels:
- it is a durable material with low dead weight;
- this is a modern finishing material, the plastic surface of which can be made in any color;
- is an energy-efficient material due to the use of expanded polystyrene foam as the inner layer;
- the panels are easy to process, install and subsequently use;
- they do not rot or become moldy.
Plaster slopes
The manufacturing technology consists of installing beacons, plaster corners and applying plaster. After drying, the slopes are puttied, sanded and painted. It is extremely difficult to do high-quality insulation, since the connection between the solution and the wall is lost.
Finishing a window opening with plaster has the following advantages:
- Versatility. This material is used in rooms with different humidity and temperature levels.
- Reasonable price. Plaster is an inexpensive material, and you can also save money by doing the work yourself.
- Strength. Plaster slopes are more resistant to mechanical stress compared to other types of finishing.
- No seams. Perhaps the main argument of supporters of such a coating is that there is no need to additionally process the joints and interfaces of the opening planes.
- Possibility of updating and repair.
USEFUL INFORMATION: Plastering window slopes with your own hands
But a number of serious shortcomings have led to the fact that plaster is used less and less for work of this kind:
- Duration and complexity of the process. Finishing takes considerable time: each layer of the plaster mixture needs to dry.
- A large amount of dust and dirt, risk of scratching the window.
- Low thermal insulation properties of plaster. Such slopes are prone to freezing in winter and condensation. In addition, when installing them, you have to cut the foam one or two centimeters inward, weakening the thermal insulation seam.
- Detachment from frame. It is impossible to firmly connect the plaster and the PVC frame. There are no sealants with equally good adhesion to both materials. This leads to the formation of cracks between the window block and the plaster layer.
USEFUL INFORMATION: Adjacent profile for window slopes
The last two drawbacks can be eliminated by insulating the opening with penoplex before plastering and using an adjacent window profile with reinforcing mesh.
USEFUL INFORMATION: How to putty the slopes on windows?
Expert opinion
Anton Tsugunov
Construction expert. Entrepreneur. 17 years of experience. More than 100 completed objects.
Today this is the dirtiest and longest finishing method. To avoid problems with condensation and mold, I recommend choosing this method only in warm rooms, for example, when a window is installed between a heated balcony and a living room, then freezing of the slopes is excluded. And also if there is simply no room left to install sheet material. For plastering warm slopes, I have been using Rotband plaster from Knauf . I buy it only from a trusted supplier.
This is better than going to the store, standing in lines first at the checkout, and then at checkout. The mixture is delivered to me directly to the site at the agreed time. It’s more convenient and safer!
Plastering
Another way to finish windows is to apply plaster. This method can be used only in cases where the surface of the slope is perfectly flat and smooth. The thickness of the application of the plaster composition should not exceed 2 cm, since thicker layers are susceptible to rapid cracking and crumbling. Plastering includes the following technological stages:
- removing dust, dirt, applying antiseptic;
- priming with special mixtures;
- applying the initial leveling layer;
- reinforcement of the slope surface;
- finishing plaster, painting.
Applying plaster
Drywall slopes
To make them, pieces of gypsum board of the required size are used, which are screwed to a profile frame or glued to the sides of the opening. Then the surface of the drywall is primed, puttied and painted. In the case of laminated gypsum board, no further finishing is required. The space between the wall and the new slopes is insulated with polyurethane foam and insulation.
Attaching gypsum boards is easier and faster than creating a flat surface with plaster. But we must not forget that after installation, finishing is required, which will take several days. If you use laminated gypsum board, then the installation of the slopes is carried out in one day.
USEFUL INFORMATION: Drywall slopes: do-it-yourself installation
Advantages of using drywall:
- Low cost.
- Easy to install. Requires very basic construction skills.
- The ability to easily create perfectly smooth surfaces.
- Additional insulation.
- If preparation for staining and painting was carried out, then a simple repair, suitable for repeated repainting.
- If you use a good semi-gloss and gloss paint, you can wash the slopes many times.
- During finishing preparation and painting, it does not require the installation of plastic corners.
We recommend
Roller blinds of closed type.
Attaches directly to the frame, no drilling required.
Excellent protection from the sun and heat.
They don't take up space.
Many colors and sizes.
Price from 1,700 rubles for a complete set. Delivery is free from 3 days.
Lots of positive feedback. Verified seller! Read more >>>
USEFUL INFORMATION: How to putty the slopes on windows?
Flaws:
- Inability to firmly bind the slope material and the PVC frame (as with the plaster version). This leads to the appearance of cracks at the joints.
- Fear of moisture. If the windows “cry”, under the influence of condensation the drywall, even moisture-resistant, gradually collapses and swells near the frame. Regardless of whether the plasterboard is laminated or painted. Judging by the reviews, this is the main reason for refusing to use gypsum boards in the manufacture of slopes.
- Risk of sagging, dents and crushing. Still, drywall is a fairly fragile material.
To avoid the finishing stage, you can take laminated gypsum board instead of the usual one. But in this case, you will have to use special corners to cover the ends of the sheets.
Expert opinion
Anton Tsugunov
Construction expert. Entrepreneur. 17 years of experience. More than 100 completed objects.
I use moisture-resistant Knauf plasterboard with dimensions 2500x1200x9.5 mm . It is important to use smooth and dry sheets.
Tree
If the windows themselves are made of wood or it is used in decoration, it is logical to install wooden slopes and a window sill. To protect against high humidity, treatment with a special compound is necessary.
You can solve the issue of decorating a window with the help of furniture that goes around its perimeter: a bookcase, a wall-mounted slide, a kitchen unit. To emphasize the integrity of the composition, paint the surface in an expressive color or varnish.
Slopes made of gypsum fiber (GVL)
The technology for installing slopes made of gypsum fiber sheets is practically no different from attaching drywall, the advantages will be the same. At the same time, GVL does not have the disadvantages of GCR: it is much stronger and stiffer, and its moisture-resistant version is not at all afraid of a wet environment.
Expert opinion
Anton Tsugunov
Construction expert. Entrepreneur. 17 years of experience. More than 100 completed objects.
I believe that when installed correctly, gypsum fiber board slopes are superior to other options in terms of performance and appearance. But their use is justified only when finishing from scratch or during a major overhaul. Since during finishing it is necessary to install painting corners and putty not only the slopes, but also the adjacent wall.
USEFUL INFORMATION: GKL or GVL, which is better: differences, what is the difference, what to choose?
Advantages of gypsum fiber slopes:
- Fairly simple installation.
- High strength and rigidity.
- Possibility of high-quality insulation.
- Ideal design geometry.
- Long service life - more than 10 years.
- Maintainability: a damaged element can be easily puttied and tinted.
- Moisture resistance.
- The paint is easy to clean.
- Any decorative coverings can be mounted on GVL: from wallpaper to tiles.
Making a slope from gypsum fiber
GVL installation process
USEFUL INFORMATION: How to choose high-quality plastic windows and not overpay: professional advice
Flaws:
- Relatively high price (compared to gypsum board and plastic).
- The need for finishing.
- Cutting gypsum fiber is more difficult than cutting drywall.
If, after priming and puttying, you paint the GVL slopes with high-quality latex paint, then they can be washed without fear. And repainting will be required no earlier than after 5–8 years.
Stone
If you decide to install a window sill made of natural or artificial stone, decorate the slopes with the same material. They will look solid and will also last a long time, because both composite and natural minerals are very durable and are not afraid of dampness and fungus.
Repair of slopes from GVL
In this case, the slopes were installed more than 8 years ago. During the process of cosmetic renovation (dividing the room into two parts), the slopes were partially puttied, sanded and painted. The work on the slopes took 2 days, the cost of the work is insignificant (compared to installing new slopes - even when compared with budget plastic ones). The walls were also painted, so no corners were needed.
An entire corner of the slope was missing. Crushed from being hit by a window for 8 years.
The slope has been completely restored and painted in 2 layers.
Expert opinion
Anton Tsugunov
Construction expert. Entrepreneur. 17 years of experience. More than 100 completed objects.
I use moisture-resistant GVL Knauf-Supersheet with dimensions 10x2500x1200 mm. One sheet is enough for several windows. I order and pay with a card with 33% cashback .
Installation materials
Tools for installing plastic panels
To finish the interior window slopes with sandwich panels, you will need to prepare the following:
- Start profile.
- F-shaped profile.
- Sandwich panels.
- Wood slats.
- Insulation, if you need to insulate a window, is often used on skylights.
- Drill.
- Stationery knife.
- Level.
- Fastening (screws).
- Silicone.
- Sealant.
Many people are interested in how to cut sandwich panels for slopes, but you can cut polyvinyl chloride with a regular knife or a utility blade.
Plastic slopes
Another way to get aesthetic and reliable slopes is to cover the opening with double-sided sandwich panels. They have not only good thermal insulation properties, but also sufficient rigidity.
It is not recommended to use one-sided sandwich panels and decorative wall panels made of thin cellular plastic for finishing the window opening. They do not have the necessary strength, wear resistance and thermal insulation qualities. It is better to use special panels for making slopes.
USEFUL INFORMATION: Choosing the best window sill for plastic windows (prices)
Plastic finishing is gaining increasing popularity. The material of the slopes not only visually harmonizes with the window frame made of PVC, but is also securely fastened to it using special sealants. This method of finishing the opening has other advantages:
- Low price.
- A smooth surface that retains its properties for many years and does not require additional finishing or regular maintenance.
- No cracks or temperature changes due to the use of the same material from which the frame is made.
- Additional thermal insulation that strengthens the weak point of the window opening - the seam between the frame and the wall of the room.
- Fast installation. Plastic slopes are installed faster than plasterboard and especially plaster ones.
- Minimum amount of dirt and dust when facing with plastic.
- 100% moisture resistant.
- It is possible to replace part of the slope if damaged.
- The frame covering the outer contour reliably protects the junction of the wallpaper and the window opening.
Minuses:
- Susceptibility to mechanical damage.
- Impossibility of local repairs. If it breaks, you will have to replace the entire panel.
- Low quality of additional elements, such as corners. Often these small parts are made from recycled plastic, which turns yellow over time and stands out unattractively against the background of snow-white slopes.
- Incompatible with interior. Glossy plastic will look unnatural in a room decorated in a classic style, as well as in any other design direction where natural materials are used.
USEFUL INFORMATION: Blinds on plastic windows: install them yourself
To avoid adding others to these disadvantages of plastic slopes, you need to choose the material wisely, guided by two main rules:
- Panels must be made from virgin plastic. Only such products are absolutely harmless even when heated in the sun and will not turn yellow after a year.
- The PVC layer must be thick enough. This will help avoid damage to the slopes.
When choosing between matte and glossy plastic, you need to take into account that stains and fingerprints are more visible on a glossy surface. Matte panels look more natural and are similar to classic painted slopes.
Glossy plastic
Matte plastic
Expert opinion
Anton Tsugunov
Construction expert. Entrepreneur. 17 years of experience. More than 100 completed objects.
Depending on the width and length of the slopes, I use different plastic slopes. Here are the common sizes:
Slope width 250 mm
Length 1.5 m - Insulated window slope 1500x250x10 mm
Length 2 m - Insulated window slope 2000x250x10 mm
Length 3 m - Insulated window slope 3000x250x10 mm
Slope width 400 mm
Length 1.5 m - Insulated window slope 1500x400x10 mm
Length 2 m - Insulated window slope 2000x400x10 mm
Length 3 m - Insulated window slope 3000x400x10 mm
Slope width 600 mm
Length 1.5 m - Insulated window slope 1500x600x10 mm
Length 2 m - Insulated window slope 2000x600x10 mm
Length 3 m - Insulated window slope 3000x600x10 mm
Common mistakes
In cases where the finishing technology is not followed, serious shortcomings may soon appear. The window structure does not receive the required degree of resistance to adverse factors, and the slope elements wear out very quickly and require new repairs. To avoid such troubles, let’s look at the most common mistakes encountered during work:
- inaccuracies during measurements;
- ignoring such an important stage as applying an antiseptic and sealant;
- applying too thick a layer of plaster.
In addition, you should be very careful when choosing a finishing material so that it is suitable not only in terms of external parameters, but also in terms of performance properties. Saving in this case is also not always beneficial, since you can run into low-quality material that is hazardous to health.
Which slopes are best for plastic windows?
All slope finishing options have pros and cons. There is no ideal material that is better than others in every respect. Therefore, when choosing, you need to decide which properties and characteristics are more important in a particular case.
| Requirements for slopes | The most suitable material |
| Speed and ease of installation | Plastic |
| Durability | Plaster, gypsum fiber |
| Strength | Plaster, gypsum fiber |
| Moisture resistance | Plastic, gypsum fiber |
| Natural material, natural look | Plaster, drywall, gypsum fiber |
| Tightness of the structure | Plastic |
| Practicality, no need for maintenance and care | Plastic |
| Best maintainability | Plaster, gypsum fiber |
| Low price | Plastic |
| Original finishing options (decorative plaster, tiles, mosaic) | Plaster, drywall, gypsum fiber |
| No corners or visible frame elements | Plaster, drywall, gypsum fiber |
| Possibility to change the design | Plaster, drywall, gypsum fiber |
Brick
In a brick house, it is not necessary to finish the internal slopes if you decide to decorate the interior in an industrial style. Devoted fans of the loft, in the absence of brickwork, are forced to imitate it.
To enhance the feeling of negligence and roughness, “stain” the brickwork with plaster, and if you want to soften the effect, cover it with paint of a calm shade: white, brown, gray.
Wallpaper
Decorating slopes with wallpaper is a fairly old decoration technique that was used back in Victorian England. The use of this material in window openings instantly gives the room a special retro atmosphere.
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But, of course, you need to choose the right wallpaper. The most common option for decorating slopes is to use the same wallpaper that covers the walls in the room. But, of course, this is not the only option for using this material. Wallpaper can be chosen for contrast or matched with an accent wall.
