Removal of bloating under the window and warming of the sewing assembly (Minsk)
A common problem with plastic windows — especially in new builds or after a poor installation — is draughting between the windowsill and the frame. The warm air from the radiator, which is supposed to warm the window, simply escapes outside through gaps in the installation seam. Here's how I tackled this task in one of the Minsk flats.
Diagnosis: how the problem was found
The client complained of cold coming from the bottom of the window, even with the sash closed. First I tapped the windowsill from above — a characteristic hollow sound immediately pointed to voids beneath it. But to be sure, I removed the external drip cap. The picture was as expected: the installation foam was missing in many places, and air passed freely through the gaps. The thermal envelope was broken. The main defects visible were:
- Voids under the windowsill, through which cold penetrated.
- Poor filling of the installation seam with foam around the whole perimeter.
- The drip cap didn't fit tightly and didn't protect the seam from moisture.
The first window: work through the support profile
I drilled holes in the support profile and injected foam through them. When the foam starts coming out of the holes, that's a sure sign the cavity is filled. After that I:
- foamed along the whole window, under the future drip cap;
- fitted the drip cap, seating it on the fresh foam — this additionally insulates the bottom of the window and reduces noise during rain;
- fixed the drip cap with press-washer screws;
- filled the joint of the drip cap with the wall using acrylic sealant.
The second window: the glass unit had to be removed
On the second window, reaching the far areas under the sill through the bottom profile wasn't possible — the roller-blind guides glued onto the beads got in the way. Fortunately, the size of the window allowed the glass unit to be removed for full access. After dismantling, a more detailed picture emerged: the drip cap looked well seated on foam, but on close inspection some gaps were found. I carried out all the same steps: drilling, filling with foam, fitting the drip cap on foam, and sealing the joints.
The result
After the work was finished, the windowsill stopped being a source of cold. The thermal envelope was restored and the draughts disappeared. The client noted that the room had become noticeably warmer, and the work was done from outside, without touching the interior finish.
Order bottom-of-window insulation in Minsk
If cold comes from under your windowsill, the cause is almost always voids in the installation seam. While it's warm, I can fix this in a single visit, without removing the sill. Call me — I'll find the problem spots and bring the warmth back to your window.
📞 Phone: +375 (29) 135-50-50 · 🌐 rpo.by · Brand: Spravnae Akenca
