By default, the platform does not have this option. You can use the following CSS code to adjust the header height.

Please follow the steps below:

1. Go to BuddyBoss > Theme Options

2. Under Custom Codes, enable CSS

3. Append the following:

.site-header,
.site-branding,
.header-aside > *,
.user-link,
.header-aside .notification-wrap,
.header-aside .notification-link,
.default-header .main-navigation,
.site-header .site-header-container.flex
{
    height: 35px !important;
}
.primary-menu > li{
    line-height: 35px;
}

4. Save changes 

Note: Any modifications are considered as custom work already. Know more about our Support policy here: https://www.buddyboss.com/support-policy/