Boolean

https://imageshack.com/i/0i138ygΒ

Split the windows into separate objects and boolean one at a time.

Boolean in Nvil not very good at times.

Also it is prolly faster and easier to just model the windows in.

During my modeling days inside maya, which had a poor boolean modeler I had to work around its failure to reach results.

In your case, just use 1x window and use boolean on a cube, and then delete the unwanted geometry and then weld it to the parent geometry.

Nvil could really benefit with a modern boolean solution.

Boolean very important for me, I actively use it in the style of hard surface
In my opinion the best booleal in bledner, as it makes the modifier, the first mesh can be moved at any time, + to this, he quickly and without making vycheslenie and rarely falls
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Boolean для мСня ΠΎΡ‡Π΅Π½ΡŒ Π²Π°ΠΆΠ΅Π½, я Π΅Π³ΠΎ Π°ΠΊΡ‚ΠΈΠ²Π½ΠΎ ΠΈΡΠΏΠΎΠ»ΡŒΠ·ΡƒΡŽΡ‚ Π² стилС hard surface
На ΠΌΠΎΠΉ взгляд самый Π»ΡƒΡ‡ΡˆΠΈ booleal in bledner, Ρ‚Π°ΠΊ ΠΊΠ°ΠΊ ΠΎΠ½ Π΄Π΅Π»Π°Π΅Ρ‚ ΠΌΠΎΠ΄ΠΈΡ„ΠΈΠΊΠ°Ρ‚ΠΎΡ€ΠΎΠΌ,, ΠΏΠ΅Ρ€Π²Ρ‹ΠΉ mesh ΠΌΠΎΠΆΠ½ΠΎ ΠΏΠΎΠ΄Π²ΠΈΠ½ΡƒΡ‚ΡŒ Π² любой ΠΌΠΎΠΌΠ΅Π½Ρ‚ ,+ ΠΊ этому ΠΎΠ½ быстро ΠΈ Π±Π΅Π· Π΄Π΅Π»Π°Π΅Ρ‚ вычСслСния ΠΈ ΠΊΡ€Π°ΠΉΠ½Π΅ Ρ€Π΅Π΄ΠΊΠΎ ΠΏΠ°Π΄Π°Π΅Ρ‚

Meshfusion is very powerful as well, probably the best on the market because it supports fillets.

aga, Only I have no money to buy a computer for $ 10,000 to vnem normally raboat
I tried it VERY slow and constant lags ,+ nly works sds

In my opinion the best booleal in bledner, as it makes the modifier, the first mesh can be moved at any time, + to this, he quickly and without making vycheslenie and rarely falls

Blender uses Carve CSG