Errors in the installation of metal-plastic windows

Recommendation points

• Errors when measuring a window opening
• Errors when dismantling old windows
• Errors in setting the window to a quarter
• Installation without wedges and keys, or incorrect positioning
• Installation without a window sill profile with an external sill to the frame
• Failure to comply with the location of the attachment points

In the modern market of metal-plastic windows, the consumer has a lot to choose from. Numerous companies – large and small – offer windows from the profile of various manufacturers – well-known and not so. Typically, buyers focus on the choice of profile and insulating glass, studying the “pedigrees” of manufacturers and carefully tracking reviews of their products. Few people care about installing a window, because the seller guarantees a full range of services. Meanwhile, mistakes in measuring window openings and installing windows are much more likely to cause inconvenience and disappointment to consumers than insufficient quality of a profile or a double-glazed window. What are the most common mistakes and shortcomings??

Errors when measuring a window opening

Do not worry if the window is large – you will still “push” it into the opening, but … If the window is wider than necessary, you will not be able to compact the slopes. If it is high in height, there is not enough space for the low tide, the window sill and the window sill profile. No clearance required for thermal expansion. As a result – wetting of slopes in winter, deformation of frames and destruction of glass units due to thermal expansion in summer.

It seems that there will be no problems if the window is not enough, except perhaps the excessive consumption of polyurethane foam. But in this case, the fasteners experience increased loads due to an increase in the bending moment. In strong winds, the joint looses, plaster crumbles.

Therefore, even if you do not understand anything about repair and construction work, personally control the process of measuring the window opening. Please note that measurements are taken at three levels (bottom, middle, top) and along three vertical lines (along the edges and in the middle), you must also measure the diagonals. It is also advisable when measuring to open the slopes of the window opening and take the dimensions of the old frame. When determining the size of the window, it is imperative to take into account the thermal expansion gaps.

Errors when dismantling old windows

In an effort to complete the installation of a new window as quickly as possible, the performers often neglect the preparatory operations. They leave construction debris in the opening: fragments of wood, plaster, rags. In this case, the so-called thermal bridges are formed – the remains of the old structure and pollution “pull” moisture from the atmosphere. In addition, debris interferes with the adhesion of the polyurethane foam to the wall..

Make sure that before installing the window, all contact surfaces are clean, the voids are filled. It is especially necessary to remove small construction debris and dust from the bottom of the window opening.

Errors in setting the window to a quarter

Installing the window in a quarter without leaving a gap for thermal expansion makes it impossible to seal the joint with special gaskets. A gap is left without a seal, allowing cold air and moisture to pass through. As a result, noticeable moisture in the plaster, smudges and mold, first on the slopes, and then on the walls. In winter, there is also condensation on the slopes and near the frames..

Conclusion – when installing windows, it is necessary to check with the masters what gaps are left for the seal. When using polyurethane foam as a sealant, the gaps should be 10-15 mm (depending on the size of the window and the type of profile), if an expansion tape is used – 8 mm.

A common mistake with very wide quarters is to set the window frame completely behind the quarter. In this case, water flows into the folds of the sash and enters the room. In winter, the gaskets not only get wet, but also freeze to the frames, condensation appears on the sashes. Also, with wide quarters, too large gaps are often left on the side of the slope. In this case, the mounting pin sags in the air due to the increased bending moment. Under the influence of the wind, the window moves in the transverse direction, the seal stops working, and water flows into it. As a result – a draft in the room, condensation at the junction.

It is correct for wide quarters to use wide frames of boxes or special elements that extend the frames. Even if you do not know what “quarter too wide” is, please discuss this issue with the installer. By showing your awareness of some of the nuances of installation, you will make them take a closer look at the execution of your order.

Installation without wedges and keys, or incorrect positioning

Unscrupulous installers neglect such trifles as supporting dowels (wedges) and install the window directly on the slope, which excludes the possibility of sealing the window from below. It happens that they are only “slightly saved”, which is fraught with “sagging” windows in the impost area. Without side keys, the window is not vertically aligned. They can also install a window without side spacers or use brick fragments instead. And the brick can freeze.

If the installation of windows is carried out using all the necessary accessories, you should pay attention to its quality. The keys must be made of durable materials with high heat-shielding properties. They must be securely fastened at all “strategically important” points (corners, impost, window connections). The dowels (wedges) must ensure a secure fit of the window, do not interfere with the installation of thermal insulation and, subsequently, the thermal deformation of the profiles. Side keys must be removed after installation.

Installation without a window sill profile with an external sill to the frame

With such a marriage of the installation, water can penetrate under the window frame and then into the room. Further, the wall under the window begins to get wet, the tightness of the connection is broken, in winter the wall freezes, pins, anchor bolts and dowels corrode.

The sill profile must be used without fail. It ensures a good seal under the window and the correct installation of the window sill and ebb.

Failure to comply with the location of the attachment points

It is common to fasten the window at four points on the sides. The distance between the fasteners is regulated by the installation documentation and depends on the size and weight of the structure. In this case, attachment to the upper and lower slopes is required. Failure to comply with the basic rules for the location of attachment points leads to deformation of the window, loosening of the seal, shedding of the plaster.

In addition to the basic ones considered, unscrupulous or unprofessional workers can make many other, less significant, but no less annoying mistakes. This is the wrong sealing of the window in the walls with a quarter or without a quarter, incorrect placement of the window in the opening, too tight fasteners. Mistakes are often made when installing windows in walls with internal or external insulation. And just the excess of polyurethane foam not cut off in time and the protective tape not removed immediately after installation will give you unnecessary trouble. Therefore, you should not completely rely on the professionalism of the assembly team. When installing windows, the customer must be present and monitor the quality of work.