Lately we have been utilizing a drawer style navigation in our designs to provide a better user experience in our websites. The request for quite a bit of content in the drop downs themselves (mega drop downs that span the full width of the site no matter which tab you have clicked) in some of our more complex higher-ed sites also creates the problem of covering up the content of the site and proving tricky when the site responds to mobile screen sizes. Putting the navigation in a sliding drawer is proving to be a unique solution that translates beautifully to mobile in responsive design.
If you look on Mashable, a popular news article site, the nav drawer does not shift the page down, but is a full width mega drop down menu. Compare to the University of Wyoming, a site recently developed by Beacon, which has a drawer based nav.
Whether or not this is the right nav for your site will probably be based upon a lot of factors like what type of content is in your drop downs and what type on content is on your homepage. If you have a lot of content in your navigation it may be worth while to put that navigation in a slider so that the homepage remains visible, even when the navigation is open. Also, you need to think about what your navigation does on mobile devices and tablets and how to best integrate this with your drop downs. Mashable.com serves up a different navigation for it’s tablet users, for example, simplifying the menu, so they put it in a side drawer. On the higher ed sites we develop here at Beacon, we need to provide a consistent navigation for users on every type of device, so we might use a similar drawer on both mobile and desktop, but just change the navigation to stack taller on smaller devices and open and close subsections. This also can allow us to integrate deeper navigational tiers in the main nav on mobile devices so we can keep the content area cleaner and simpler.
This solution can be elegant and it even translates very well to touch devices that do not have the ability to open menus on-hover. This keeps the experience more consistent through all the screen sizes by utilizing an on-click drawer.
Ultimately decisions like these need to be made on a case by case basis.