Is swapping out the entire Left-Local-Side-Nav a bad idea?

Question

We have a large Website with hundreds of pages. We have a horizontal global navigation, and a left-local-side Nav to navigate through a group of related pages.

As I was browsing clicking down from the top to the lower links in the local Nav, one link **replaced the entire side nav with another group of side nav links". I became lost and confused. It took several seconds for me to realize what happened.

Intuitively, I think the local side nav should never be swapped with an internal click inside itself.

Is it just me, or is there some truth behind this?

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Answer 1

Before I address your actual question, I have to point out..

I have seen this layout many times and it always annoys me - the problems I see with that layout are:

• Global menu takes you out of current site, yet appears to be a part of the site

• Site menu is in a different region of screen, making it confusing - which menu are you supposed to look at?

• Site menu is to the left of the content, thus taking your attention away from the content

I think that a more intuitive layout would be (from top to bottom):

• Global navigation at top most region of site (above logo) - as clicking on these links effectively take you to another site.

• Logo with customization for current site (e.g. company logo + a site element added to it)

• Site menu

• Content

Now to your actual question:

If clicking on a link opens a page/site with it own sub menu, I would use one of the following techniques:

• Expand its menu in place (e.g. with an accordion control or a tree menu (assuming menu is at the left))
• Add a sub menu under the current menu (assuming menu is at the top).

^{download bmml source – Wireframes created with Balsamiq Mockups}

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