How to cover the foam after installing plastic windows, what materials are best to seal the cracks, gaps, seams, joints between the window sill and the PVC frame, in the opening?

The formation of gaps and cracks after installing a PVC window is an inevitable result of the technology of installation and construction work.
They arise between the frame and the wall and require special sealing to prevent moisture from entering both the window structure and the interior of the room.

Often, when installing a window unit, installers only foam the installation seams; the rest of the PVC window sealing processes are carried out by the owners themselves. Therefore, even before installing the window unit, you need to select the sealing method and sealing materials in advance.

What are seams and gaps?

The gap between the wall and the frame appears due to the fact that the window design is slightly smaller in size than the technological opening in the wall. These are the requirements of the technological map and GOST for installing a PVC window block to provide space for thermal expansion of the window frame. Ideally, such seams are foamed, then waterproofed and sealed with putty and sealant.

Advantages of using foam to seal mounting gaps when installing PVC windows:

high level of free space filling;
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ability to bear high loads;
high characteristics of moisture, noise and thermal protection;
low cost;
high speed of work;
simple application process;

The disadvantages of polyurethane foam for sealing installation joints include:

Its high susceptibility to UV rays, therefore, after hardening and removal of excess, it must be covered with finishing and protective waterproofing materials.
Foam at high temperatures can expand up to 10%, and at low temperatures, on the contrary, shrink.

Where exactly is sealing required after installation?

If the technical installation of PVC windows in the wall is carried out correctly, cracks will form :

between the frame and the top and vertical walls;
between the window sill and the frame.

If the installers follow the technology for installing the block, then such gaps do not exceed 2 cm, this is enough to ensure thermal expansion of the window frame. If the foam was applied correctly during installation work, then the completion of the sealing of the window block is carried out using putty solutions and sealant

What to treat, what to wipe off

After carrying out work using polyurethane foam, it may be necessary to remove excess foam not only from the surface of the seams, but also from nearby structures. In order to wipe off fresh or hardened polyurethane composition from metal surfaces, plastic windows, clothes and hands, folk and special means . Removing foam with a cleaner allows you to get better results. The range of large manufacturers of polyurethane foam also includes high-quality cleaners.

Why do you need to seal and close knots?

Since the main material that can be used to seal mounting cracks in window openings is construction foam, which can be destroyed under the influence of precipitation and UV radiation, it requires protection. After the foam layer is leveled from sagging, it must be waterproofed and covered with finishing materials. If this is not done, the foam will collapse very quickly and through holes will be exposed.

Technology for sealing technological seams created when installing PVC windows:

When installing the block, they try to ensure that the distance from the wall to the PVC frame does not exceed 2 cm. This is achieved by accurately measuring the wall opening before ordering the window block.
Fill the seams with polyurethane foam, purchased according to the outside temperature in the area of installation work.
Trim off excess foam after it dries
Install a vapor barrier layer.
Plastering.
Paint the plaster layer.

After this, the window sill, drainage and slopes are installed. They seal small gaps up to 5 mm between the frame and the wall opening, as well as the frame, drainage and window sill.

The feasibility of treatment with construction foam

This insulation is a high-quality sealant, the main task of which is to efficiently fill all voids and bond surfaces together. Polyurethane perfectly connects two surfaces, which can include brick, natural wood and even concrete. This material can be used as a reliable waterproofer and a means to combat extraneous noise.

High density and strength appear only under certain operating conditions. Due to exposure to rain, snow and bright sun rays, the final performance will gradually decrease. After several years of use in improper conditions, the foam will simply begin to delaminate, and voids of different diameters and cracks will form in the seam.

This situation is fraught with complete resolution. That is why experts recommend sealing the seams with special solutions. After final hardening, the foam acquires a characteristic light beige tint. If the material turns brown after some time, then the process of gradual destruction can be considered complete. In such a situation, it is necessary to again clean the window opening from the previously used sealant and carefully close all the seams.

Sealing joints

What materials are best?

After the polyurethane foam is applied and the window sill, drainage and slopes are installed, even with the most careful execution there will still be small gaps that are sealed with sealants.
In the retail chain you can purchase several dozen very effective sealants for PVC windows. They contain various polymers that give them certain characteristics.

The form of implementation is tubes with a pasty and plastic mass, most often white. After the sealant is applied to the surface that has leaks, it gradually hardens, creating an airtight and moisture-resistant layer.

Let's look at the most popular types of sealants for sealing between structural seams of PVC windows.

Silicone

Available in the form of a universal paste of organosilicon compounds, intended for internal and external use. There are acidic and neutral types.

Advantages:

high elasticity and good adhesive properties;
ease of surface treatment and affordable cost;
the resulting seam does not shrink;
does not lose elasticity or color over time.
For interiors, sanitary silicone sealant is used, which resists the formation of mold and other biological damage, so it always remains white.

To the disadvantages:

the presence of the smell of vinegar in the room when applying acidic compounds;
Over time, the smell dissipates.

Acrylic

The sealant is used for external work.

Advantages:

increased elasticity;
moisture resistance;
resistance to UV rays;
low cost.

The disadvantages include:

high moisture absorption;
in a liquid state it is easily washed away by water, in a solid state it absorbs room vapors, after which it darkens, so it is not recommended for indoor installation.

Liquid plastic

The material is produced on the basis of PVC from MS polymers.

Advantages:

excellent adhesion and increased viscosity, as a result, after application with the base material, it forms an integral system;
After the sealant has hardened, it can be coated with a layer of varnish or paint.

Flaws:

high price;
cannot bear the load.

Butyl or polyisobutylene sealant

It is produced on the basis of a rubber-like substance.

Advantages:

high characteristics of elasticity and resilience, which are maintained at temperatures from -55 to +100 C;
endurance of ultraviolet exposure;
environmental and biological safety;
high vapor permeability, therefore, in addition to sealing installation joints;
additionally used for repairing double-glazed windows;
is highly water resistant;
does not swell.

The disadvantage is the low-strength composition.

Theocol sealant

Produced using polysulfide components.

Advantages:

hardens at any air temperature and humidity;
indispensable for external work;
can be used in frost and precipitation.

The disadvantages of this type of sealant include:

high price due to the large number of components that give it rubber-like characteristics;
unpleasant smell.

Steez A

Acrylic sealant with a one-component composition, area of application for outdoor work.

Advantages:

highest adhesion to a variety of building materials;
resistant to ultraviolet radiation, natural precipitation and shrinkage deformation processes;
can work at T=-20 C;
high vapor permeability;
can be painted in the desired color;
resistance to mechanical loads;
durability up to 20 years;
minimal shrinkage and the presence of antibacterial components.

Flaws:

insufficiently high elasticity lower than that of silicone analogues;
porous structure;
unpleasant odor;
short shelf life of the prepared mass from 6 to 12 months.

Steez B

Acrylic one-component sealant for interior work.

Advantages:

high adhesion to any type of wall;
highest vapor barrier;
wide range of application in temperature from -40 to +80 C;
resistance to deformation;
can be painted after drying;
lower price than modification A.

Disadvantages: it is not able to remove moisture from the seam, so it can only be used for interior work in conjunction with Steez A.

Steam and waterproofing tapes

The materials must be used to create a warm seam system using PSUL - a vapor-permeable self-expanding sealing tape.

Advantages of PSUL Euroband:

waterproofing and vapor barrier protection covers the internal seam and does not create mold;
has a high level of elasticity;
do not harden during operation;
takes any shape, resistant to UV rays, 5-fold expansion coefficient;
water resistance up to 600 Pa;
fills various cracks;
removes moisture from the wall structure;
unable to support combustion;
chemically neutral.

to be a disadvantage .

Sealant protection options

Despite the excellent characteristics and properties of polyurethane foam, all products in this category are destroyed when exposed to sunlight. First, the material acquires a brown tint, decreases in volume, and then gradually spills out of the joints and gaps. Polyurethane foam in the sun is destroyed by sunlight. Negative processes can last from a year to several years. This depends on the quality of the sealant, the angle of exposure to ultraviolet radiation, the thickness of the applied layer and other factors. How to protect mounting foam from the street from UV rays:

Treatment with putty compounds. These include liquid plastic, finishing plaster with the inclusion of frost-resistant additives, window putty with the addition of liquid glass. The mixture is applied with a spatula from bottom to top along horizontal and vertical seams.

2.You can paint the installation sealant with paint or treat it with varnishes for exterior use. The best way to protect a polyurethane product is an acrylate composition, which has high adhesion to installation sealants. To obtain long-term protection, the foam is first treated with putty, and then with acrylate paint.

3. Mounting tape. This is a temporary measure, since the material will be constantly exposed to precipitation and temperature changes. In a hardware store, you can choose adhesive tape to match the color of the window frames or the frame of the front door. But every few months the tape needs to be re-glued.

Fire-resistant foam can be protected with a layer of plaster 8 cm thick. But the best option is to prime and paint the surface. To prevent the destruction of the polyurethane foam, a cement-sand mortar is sometimes used, to which a small amount of white grout is added to improve decorative characteristics.

On video: Protecting foam from ultraviolet radiation.

TOP 5 funds

The popularity of a particular sealant is determined by the purchasing activity of large trading platforms. And also based on customer reviews. Among the sealants for sealing the seams of PVC windows, the following materials are the most popular.

Cosmofen 345

Liquid plastic from a German manufacturer. The place of sealing is between a quarter of the brick wall and the frame from the outside, option: PSUL + finishing + Cosmofen 345.

Advantages:

excellent adhesion to all wall materials;
increased resistance to ultraviolet radiation and atmospheric moisture;
long service life of more than 20 years with preservation of original properties;
efficiency and convenience of work;
low shrinkage;
capable of sealing seams up to 7 mm, ready in 24 hours.

The disadvantage is that it has a strong, toxic odor, so it can only be used outdoors.

The cost of a 310 g tube is 590 rubles.

Quelyd 007

Universal sealant for internal and external use from France. Installation location - outside side and top walls, option: PSUL + finishing + Quelyd 007, inside side walls, top wall and window sill, scheme: vapor barrier tape + finishing + Quelyd 007.

Advantages:

multifunctionality;
high moisture resistance;
neutral smell;
does not float;
has minimal shrinkage.

There is only one drawback - high cost. The price of a 430 g tube is 650 rubles.

Soudal fix all high tack

Belgian universal sealant made of synthetic rubber. Installation location - outside side and top walls, option: PSUL + finishing + Soudal fix all high tack, inside side walls, top wall and window sill, scheme: vapor barrier tape + finishing + Soudal fix all high tack.

Advantages:

high water resistance can glue even wet surfaces;
instant gluing effect;
high resistance to aggressive environments;
wide range of operating temperatures;
long service life.

The disadvantage is the high price, a 290 g tube costs 950 rubles.

MasterTeks ProfiMaster

Polish universal transparent acrylic sealant. Installation location - outside the side surfaces and the upper part of the opening, option: PSUL + finishing + MasterTeks ProfiMaster, inside the side walls, top wall and window sill, scheme: vapor barrier tape + finishing + MasterTeks ProfiMaster.

Advantages:

high antibacterial resistance;
highest adhesion;
the widest range of permissible temperatures from -20 to +80 C;
can be painted;
reaches elasticity an hour after application;
lends itself well to correction;
relatively low price;
long service life.

Flaws:

turns from white to transparent when dried;
painting required.

Price - 570 rub. for 1 tube.

Moment

White universal silicone sealant made in Russia. Installation location - outside side surfaces and upper part of the opening, option: PSUL + finishing + Moment, inside side walls, top wall and window sill, scheme: vapor barrier tape + finishing + Moment.

Advantages:

high resistance to chemicals;
high degree of protection up to T+150 C;
good adhesion with all types of wall materials and PVC;
does not provoke corrosion processes in contact with metal.

The disadvantage is the presence of an odor at the time of application, which later dissipates.

Price per tube - 350 rubles.

Introduction to the topic

After installing windows and doors, the resulting gaps are sealed with installation sealant. The composition, which is in a cylinder under pressure, expands as the substance interacts with atmospheric moisture. Therefore, excess foam remains on the inside and outside of the structure. They are carefully trimmed with a construction knife, after which the polyurethane foam needs to be protected from the sun.

Ultraviolet rays destroy the structure of the mounting sealant if the surface is not treated with anything. The use of different methods of protection allows not only to preserve the properties of the porous mass, but also to give the installed structure a decoratively attractive appearance. For finishing treatment, painting, puttying, plastering, and priming are used.

Tools

To seal seams and cracks, you will need a variety of tools, the list of which can be expanded depending on the width of the cracks and the selected processing technology.

If the frame is installed according to the project, then the gap between it and the wall opening should be about 20 mm, in this case the following tools, devices and consumables :

Master OK.
A set of spatulas, including an angular one.
Mortar container.
Construction level, plumb line.
Soft wide brush.
Construction float.
Electric drill with a mixer attachment for preparing finishing slopes.
Gun.
Container with water.
A towel or piece of clean cloth.
Degreaser.
Construction foam.
PSUL.
Vapor barrier tape.
Sealant or liquid plastic.
Primer composition.
Reinforcing fiberglass mesh.
Construction tape.
Sponge and napkins.

Step-by-step instructions for sealing

The technology for sealing installation joints depends on the wall material, window design, selected consumables and scope of work. The main operations that the contractor must perform when sealing and sealing assembly seams and gaps between the surfaces of structures:

After fixing the frame and installing the window, all mounting cracks are foamed with construction foam.
PSUL is installed between the quarter and the frame.
There is a diffusion tape between the frame and the ebb.
Between the frame and the window sill there is a vapor barrier tape.
Between the frame and the internal slopes there is a duplicate vapor barrier tape.
Slopes are made with insulation and waterproofing.
Next, they begin to seal the gaps between the PVC window frame, slopes, drainage and window sill board.
Prepare a syringe for sealant and a vessel with water.
Construction tape along the edge of the seam is used to protect all mating surfaces.
Before starting work, clean the work area from dust.
Window sealant is applied with a syringe at an acute angle, squeezing it into the cracks and at the same time using the spout to smooth out the seam.
The protruding areas of the seam are smoothed with a wet finger, trying to evenly distribute the sealant along the entire length.
Excess sealant is collected with a damp sponge, which must be constantly cleaned of glue in a container with water.

To ensure that the applied sealant does not harden, the work is carried out in sections. If the surface of the frame or window sill needs to be degreased first, acetone should not be used for this purpose.

Protection Features

To increase the service life of the sealant, you need to choose a high-quality putty. The working mixture is prepared according to the manufacturer's instructions - the proportions of the solution with water are indicated on the packaging. The solution should have a thick, uniform consistency. The mixture must be applied perpendicular to the seam - this ensures a more dense filling of voids and cracks.

The putty is distributed not level with the height of the joint, but with a slight excess. Before painting, the excess compound is sanded with sandpaper or construction mesh for finishing work. The putty should be rubbed down after it has completely dried so that the solution does not “smear.” The result is a smooth base on which the paint lies smoothly. It must be resistant to low temperature and moisture, suitable for external processing of products and structures.

Possible difficulties and errors

The first errors due to improper sealing will be detected by the owner of the window immediately when cold weather sets in; such a window begins to siphon from under the installation seams, and condensation appears abundantly outside and inside the structure, while the slopes turn black with mold.

If these signs were discovered by the owner on PVC windows, and their installation was carried out by a specialized organization, then their representatives urgently need to be invited to eliminate the defects.

If the work was carried out independently, then most likely the following gross mistakes :

improper installation, excess thickness of the gap, for which the protective “pie” was incorrectly selected and installed;
unprepared surfaces for sealing seams;
Incorrectly selected polyurethane foam for temperature application;
protective heat and waterproofing layers have not been installed before the external finishing of the mounting slots;
the sealant was selected incorrectly, without taking into account the area of application: external or internal;
the surface is not prepared for application of sealant;
The sealant is placed unevenly on the protected surface with gaps.

External slopes: what are they for?

The finishing of external slopes should not be postponed, as they protect the thermal insulation layer from degradation, and structural elements from environmental influences.

Proper preparation of the outer part of the opening significantly increases the sound and heat insulation properties of the double-glazed window. In addition, it will make your home much more attractive from the outside.

Most often, plaster or various facade mixtures are used for such work. It is recommended to lay them in several layers, and the previous one must dry normally before applying a new layer.

After the last layer has dried, it needs to be painted - this will provide additional protection from moisture and temperature.

Prices for services of masters

The cost of sealing seams depends on their size in width, total length in linear meters, the level of preparation of the treated surfaces, the number of floors the window is located and the protection technology adopted. The work can be carried out comprehensively, for example, during the installation of PVC windows or in individual technological operations.

Average prices for the service of sealing seams after installing a PVC window:

Comprehensive sealing of PVC windows after installation, RUB 2,000. per set.
Sealing of external seams - 600 rub./l.m.
Sealing of internal seams - 300 rub./running meter.
Sealing of seams between PVC frames and slopes 300 rub./l.m.
Filling empty technological gaps between the frame, walls, ebb and window sill with foam - 150 rub./l.m.
Installation of PSUL - 250 rub./p.m.
Seam protection with steam and water protective tapes - 300 rub./l.m.
Preparation of surfaces for sealing - 300 rub./l.m.

Popular methods: how to cover the polyurethane foam outside and inside the window after installation?

Photo from the site: obalkonah.ru
Plastic and metal-plastic windows are becoming more and more common today, although some twenty years ago they could be called a real curiosity, accessible only to wealthy people. Everything is changing, and in the modern world new technologies are being introduced more and more, and mastering them, learning how to correctly perform certain actions, correctly install, and then care for structures, is already our direct task, if the laurels of a true home craftsman give no rest.

In fact, there is nothing complicated, and, for example, how and with what to cover the foam after installing plastic windows can be figured out by anyone if necessary. Let's clarify a few nuances and present some options that will greatly simplify the task and allow you to cope without the outside help of a professional craftsman, whose services, as you know, are not cheap at all.