Blowing from plastic windows: what to do and how to fix the problem

When plastic windows appeared on the market, they were advertised as airtight, reliable, windproof, soundproof... it can take a long time to list the "advantages".

In reality, you often have to see a different picture: puddles on the windowsills, mold in the corners, blowing, freezing, etc. I tried to collect the most common faults and their methods elimination.

Blowing along the perimeter of the sash

Usually, it comes through from under the opening sash for two reasons:

• The clamp to the frame is incorrectly adjusted.
• The rubber bands are worn out.

To fix the problem, I recommend calling the wizard. But if your arms grow out of the right place and you are confident in your abilities, you can do everything yourself.

A seal can be considered unusable if it is "hardened", it has cuts, tears or local dents. We rewrite the brand of the window profile, just in case we take pictures of the rubber band and are looking for the same in the local construction market. The seller can tell you how to properly install the seal and what to look for. If you have not been advised on the market, you can easily find instructions on how to change the gum on your profile on the Internet.

If all is well with the seal, adjust the pressure. Do not press the sash too hard against the frame. You will get rid of blowing, but the seal and fittings will wear out faster. There are a lot of videos on the pressure adjustment on YouTube. Here's a good guide:

The slopes are blown

Usually the windows are installed by one company, and the slopes are made by another. When the slopes freeze, they are blown through, condensation, moisture and mold appear on them, the extreme cannot be found.

There are a lot of reasons for slopes blowing and freezing: starting from an insufficiently foamed frame, ending with an incorrect installation depth of the window in relation to the plane of the wall. Most often, you can find the following problems:

• The installer regretted the foam. Voids remain in the slope. Condensation appears there in winter. It freezes and gradually destroys the insulation. Poorly insulated areas can be re-foamed, but it is better to remove all the insulation and re-foam everything.
• The foam seam was not protected by anything. The polyurethane foam collapses under the influence of the sun - it becomes a crumb. If the windows were installed in the fall, and the outside slopes were plastered only in the spring, the foam could collapse. Even if outwardly it looks intact, the insulation destroyed by ultraviolet light can crumble over the course of several years.
  We immediately close the foam seam with a strip. And if there are fears that the insulation has become unusable, it is better to remove it and re-foam the window.
• At the installation of the slopes, the insulation was dismantled. You often have to deal with this when making slopes with your own hands. The hardened foam is cut in the same plane with the frame and the abutments are plastered. A gap inevitably appears between the plaster and the frame. In the least insulated area, blowing begins.

Blowing from the hinges of plastic windows

First of all, you need to pay attention to the fact that there is a rubber seal at the place where the hinges are installed. After that, make sure that all self-tapping screws are present at the hinge attachment point, and the loop itself is tightly held and does not dangle.

It happens that when attaching the hinge, the thread is ripped off. The new screw is no longer screwed in, but the wind blows from the street through the remaining hole. Indeed, in each frame there are drainage holes that connect the profile cavities with the "street". The same thing happens when the hinge is loose and does not fit snugly.

Blowing from the abutment of the frame and the window sill

Blowing may be due to insufficient insulation. For good, you need to remove the old foam, remove the window sill, reinstall it and foam again. But more often they pierce the existing insulation with the nozzle of the assembly gun and finish the seam.

Ideally, there should be a PSUL between the frame and the support profile. If this tape is not available, there may be blowing. But no one wants to reinstall the tape in order to add insulation there. Therefore, they usually simply coat the joint between the frame and the window sill with liquid plastic or sealant.

Puddles appear on the windowsill

If condensation appears on the glass unit in the morning, and then evaporates, this is the norm. But the drops should not drip onto the windowsill and form puddles.

Water on the windowsill may appear due to blowing between the sash and the frame, between the frame and the slope. We discussed what to do with this above.

More often, excess condensation occurs due to high humidity in the room. To get rid of it, it is enough to ventilate the room, hang curtains (restore convection) or put a radiator under the window, if it is not there (for example, on an insulated balcony).

If the material was helpful, put a "thumbs up" 👍 and subscribe to the channel.