How to leave a blank space at the top of each page only for chapter titles in ConTeXt?

How to leave a blank space at the top of each page only for chapter titles in ConTeXt?

I have a document that looks like this:
 __________________ __________________
|                  |                  |
| Chapter Title    | .......  ....... |
|                  | .......  ....... |
| .......  ....... | .......  ....... |
| .......  ....... | .......  ....... |
| .......  ....... | .......  ....... |
| .......  ....... | .......  ....... |
| .......  ....... | .......  ....... |
| .......  ....... | .......  ....... |
| .......  ....... | .......  ....... |
|__________________|__________________|
I want to add some white space to all of the pages in the document, so that the top of the paragraphs of text aligns on all pages, like this:
 __________________ __________________
|                  |                  |
| Chapter Title    |                  |
|                  |                  |
| .......  ....... | .......  ....... |
| .......  ....... | .......  ....... |
| .......  ....... | .......  ....... |
| .......  ....... | .......  ....... |
| .......  ....... | .......  ....... |
| .......  ....... | .......  ....... |
| .......  ....... | .......  ....... |
|__________________|__________________|
How can I add some white space to the top of the text such that only the chapter titles appears in this top area and other pages without chapter titles have a blank area?