Protection class for terrace doors and windows

Hello everyone,
which protection classes do you consider recommendable for a ground floor apartment regarding terrace doors and windows, and what should be taken into account here? What costs and prices can be expected for terrace doors and windows depending on class and size?

Thank you very much!

RC2 or RC2N and attention must be paid to the correct execution by the specialist company.

RC3 is exaggerated, right? Does anyone know how much more expensive that would be in percentage terms?
And: As a layperson, can I recognize the correct execution?

Depends on (what you want to protect, RC3 is certainly overkill for normal private households). Additional costs ... Significantly more expensive, as higher demands must also be placed on the installation. Best to get offers (if you are really interested). As a layperson, if I really wanted RC2 or RC2N, I would insist on receiving the corresponding certificates. I would commission a specialist company with references and then inspect it visually.

I also know window manufacturers who offer different security levels. For example: Level 1: Fittings according to RC1 Level 2: Fittings according to RC2 Level 3: Windows according to RC2N + certificate/installation certificate, glazing with pane bonding, lockable handle Level 4: Windows according to RC2 + certificate/installation certificate, safety glazing with pane bonding, lockable handle And depending on the level, the cost varies according to what you want

Thank you! I will obtain a corresponding offer.