Wierd Gap between header and navbar

[Hemmer]

I am completely stumped as to why a gap is appearing between the menu (div id #nav) and header (div id #header) of a site I am working on. I can't see anything obvious with firebug/web developer addons, padding/margins between are both zero.

The site is at http://test.thebrochinspectors.com

I'm sure its something completely obvious, but this has me stumped...

[who]

Hard to say without seeing the css.

A couple of possibilities:
Have you set a height value for either the #nav or #header?
Have you zeroed the margin and padding for the ul / li that the navigation belongs to?

[Hemmer]

The #header div has a height attribute equal to the height of the image, #nav has no height set. The ul, li elements have no padding-top, a element has 5px padding, but not enough to account for the gap - gap is still there if I remove the 5px.

Thanks for your help all the same. CSS is here.

EDIT: This thread should really be in the CSS forum. Can a mod move it please? Thanks