Many people opt for double-glazed windows because such windows are hermetically sealed, which helps to keep the room warm. But sometimes cold air still gets through. We tell you why this happens and how to deal with it.
Glass unit device
To make it easier to detect the problem, you need to know how double-glazed windows are constructed.
Such windows most often have the following components:
- Aluminum profile.
- Air chamber.
- Glass.
- Adsorbent for moisture absorption.
- Two types of sealant: polysulfide and butyl.
Also, plastic double-glazed windows are equipped with fittings, the main elements of which are cams (eccentrics) – parts located on a bar attached to the end part of the sash. They allow you to adjust the degree of pressure of the sash to the frame. The system works simply – when you turn the window handle, the bolt mechanism acts on the lever with the bar, which begins to slide along the frame, the cams go behind the support bar located on the fixed parts of the double-glazed window. As a result, the required degree of pressure is achieved.
Why does a plastic window let in the cold?
There may be many reasons for the problems, so it is impossible to say for sure what happened to your window. Let’s figure out why the cold penetrates into the room.
Incorrect sash clamping
When installing double-glazed windows, the technicians must warn you about the presence of several types of clamping:
- Weak — the most gentle mode for the seal, which is usually chosen during installation in order to extend the service life of the glass unit. Sometimes this option is called summer.
- Strong — the mode of operation of double-glazed windows, which eliminates the possibility of blowing as much as possible. That is why it is called winter. It should be understood that strong pressure is a serious load on the seal, so it is better not to resort to it unless necessary.
- Medium – a pressure that provides sufficient protection from cool air, street noise and dust. This is the optimal mode that can be followed all year round.
If the medium mode is not enough and the window lets in cold air, try to press hard. However, do not overuse it, as the double-glazed windows will break down much faster. As soon as it gets warmer outside, switch the window back to the medium mode.
In what cases will adjusting the clamping force help:
- The window frame is slightly skewed . But in this case, a small gap is formed between the frame and the sash, through which cold air penetrates. In this case, the clamping force should be increased.
- The manufacturers made a slight mistake with the calculations, and the window sash turned out to be slightly smaller than the opening . The weak mode will not work in this case, since the overlap of the rubber bands on the frame is already minimal.
- The seal has become thinner . Of course, in this case it will not fully cope with its task and therefore it will have to be replaced. If it is not possible to do this, you can insulate the glass unit for some time by strengthening the pressure.
- The windows have lost their tightness due to long-term use . If you do not plan to change the glass units yet, increase the pressure to the maximum.
It is not always worth switching to a strong mode – sometimes the sash should be loosened. For example, if the handle on the glass unit is very difficult to turn, and it is impossible to open the window without effort.
The main question remains – how to adjust the glass unit? Take a hex key, insert it into the socket on the front part of the trunnion and turn it to the right if you want to increase the pressure and to the left if you want to loosen it.
Depressurization of the glass unit
Another common problem that usually occurs after several years of using the glass unit.
What could be the reason:
- The foundation of the house was settling, which could cause the window openings to become skewed.
- Damage to glass. In this case, partial or complete depressurization of the package often occurs.
- Imbalance of fittings, due to which the sash does not fit into the opening as tightly as necessary.
There are several ways to check the tightness of windows. The most reliable is to insert a sheet of paper between the frame and the weld, then close the window until it stops. The tightness is OK if the sheet does not fall and is easily removed.
The second method is to carry a lit candle along the entire perimeter of the glass unit. If there are no problems, the flame will burn evenly. In areas where there is no draft, the candle flame will deviate.
And the easiest way is to wet your hand and run it along the frame. With wet skin you can feel even the slightest draft. If the cold is felt very weakly, you can try to solve the problem by adjusting the degree of pressure of the glass unit. However, such a measure will not save for long.
Sometimes the problem is visible to the naked eye – condensation accumulates between the panes of glass, which turns into ice in the cold season. This indicates a strong depressurization. In this case, the glass unit needs to be replaced.
Seal wear
Wear of the rubber seal on plastic windows may well be the cause of drafts.
The problem can be easily identified by the following signs:
- The appearance of bumps on the seal.
- Color fading.
- Presence of cracks.
- Loss of elasticity.
If the seal is worn out, all that remains is to replace it. And take good care of the new one: wipe it once every 2-3 months, apply silicone grease or glycerin without fragrances. These simple measures will help extend the service life of the seal by 1.5-2 times.
Defective window construction
A low-quality plastic window almost always lets in the cold, and it will be difficult to fix the situation on your own. It is better to contact the company that left you the double-glazed windows and ask for a replacement, or try to adjust the clamping force.
Cheap double-glazed windows and plastic windows for the attic with a complex design are often defective . You should not take risks and buy too budget products from unverified manufacturers.
Errors in installation of double-glazed windows
If the window is installed incorrectly, it will let in the cold, even if you try to adjust it. A radical measure will help – reinstalling the glass unit.
What else can you do if there is a cold draft from the window?
If at first glance everything is OK with the glass unit and its tightness, the problem may be in the loose fit to the frame. We will tell you what measures will help in this case.
Insulation of slopes from the inside
Such work is carried out in order to eliminate cold bridges between the opening in the wall and the window frame. In some cases, you can get by with foaming the gaps and gluing them with waterproofing tape. This insulation option will not save you if it is very cold outside, so it is better to take serious measures.
What to do if windows let in a lot of cold:
- Prepare the work area – seal the mounting gap with waterproofing tape on the outside and with vapor-permeable tape on the inside. This will prevent condensation and excess moisture around the glass unit, and protect the metal fittings from corrosion.
- Work with the “native” slopes: isolate the metal elements, cover the surfaces with an antifungal compound. antifungal compounds.
- If the slopes are brick or concrete, close the cracks on them with cement-containing compounds. Apply a primer with antiseptic properties. Then go over with moisture-resistant plaster to carefully level the surfaces.
- Install the lathing on the slopes.
- Fix the selected insulator on top of the lathing: slab insulation, polystyrene, mineral wool.
- Mask the joints with foam.
The method of fixing the insulation depends on the selected material. For example, it is advisable to place the slabs and mineral wool on a special glue and fix them with dowels.
Sealing the cracks in the window sill to protect the window from the cold
Sometimes a draft from plastic windows is not due to a malfunction or depressurization of the double-glazed windows. The culprit may be small cracks in the window sill space.
How to close them:
- Clean the gap from dust, remove condensation.
- Dry the gap, apply degreaser.
- Using a special gun, carefully distribute the sealant around the entire perimeter of the gap.
To treat cracks in the window sill space, use transparent silicone-based sealant. Be sure to pay attention to its high frost resistance.
To ensure a comfortable microclimate in the rooms, it is worth not only getting rid of drafts, but also installing underfloor heating or installing radiators . Prepare for the cold weather in advance!
