Seal the window at the bottom with compressible tape: How to transfer vertical load?

Hello everyone,

I will soon be installing a couple of windows with window sill connection profiles in wooden reveals and am currently wondering how to best design the vertical load transfer.

For lateral sealing, I have a 3-zone compressible sealing tape in my window width and for below, from the same system, a likewise 3-zone compressible sealing tape for window sill connection profiles in the depth of the connection profile. The issue does not only concern window sill profiles, but compressible sealing tape applications with load-bearing blocks in general.

Ideas:

[*]Place load-bearing blocks only on the inside: (Suboptimal load transfer only at the inner edge)
[*]Place load-bearing blocks in the middle and interrupt/compress the sealing tape (Does the sealing tape still seal well there?)
[*]Install a load-bearing bracket or inner window sill (Again, only inner-side load transfer and interferes with the sealing tape inside)
[*]Mount with an angle bracket (I don’t know if this is a good idea. Also interferes with the sealing tapes and outer window sill)

What is actually the smartest way to do this?

Hello :-)

The compressible tape in the lower area has not proven itself due to the load transfer.

Support blocks should be sufficiently dimensioned. In your case, they should be installed under the window sill connection. The good thing is that they would then no longer interfere with any further sealing.

Then, as you already say, sealing can be done with compressible tape on the left, right, and upper parts of the window, and at the bottom with a foil sealed to the masonry. Both inside and outside.

The interruption with compressible tape and blocks will not guarantee a seal because the joint will always have a gap.

Best regards

Daniel

My father-in-law has been a window installer for 30 years. Just as describes, he installed the windows of my future neighbor two weeks ago.

It was worth a try.

I cut centered recesses into the tape (45mm wide) and placed bearing blocks (24x100mm) there. That worked well and would also be bomb-proof tight since both sides are closed. BUT

The compression tape expanded so quickly (not just at the bottom but everywhere) that 10 minutes later I could barely set the window in (even though there was a 2cm gap).

Then I couldn't push additional bearing blocks down as desired because the tape simply sealed extremely tightly.

How do you actually slow down the expansion of the tapes?

Freezing?

Yes. Or at least keep it cool in the refrigerator. Or apply [Eisspray].