Make sure you have a section placed on your page.
Set the design of your section and click save.
Text has been added to this example to demonstrate white space.
Choose the White space button and drag and drop it on the section.
Type whatever size you would like in the Height box.
Your space will show up as a grey space in the edit page.
It is transparent so you won’t see it on your actual web page. The red box is added here to show approx. where the white space is.