Extra "Space" to separate instrument groups in score layout

Hi fellows,
is it possible to have the different instrument groups (brass, percussion and strings) separated with an extra space by default?
It is common practice to at least have a larger gap between strings and the the upper part of the orchestra.
Is there an option I miss?

Thanks as always,

Welcome to the forum, Jörg. Take a look at the options on the Vertical Spacing page of Layout Options, where you can specify the minimum gap between different bracketed or braced groups.