We are going through a similar thing right now, and are not sure how to proceed either.
Any advice would be great.
If you have lots of IBLs to these internal pages you are risking them in a new naming convention. A 301 would be fine at any time and would help these specific pages when you change them.
We generally do not rename URLs, if we can help it, we would create new content on a new and proper named URL instead of changing a URL for SEs - age is good!
If you must rename old pages it shouldn't matter what your timeline is, and you would be better to wait so the SEs can see all the new changes and deep index your new site.
Redesigns usually help the site there are of course a fe exceptions if your using a CMS. Try and get some new links after the design goes live. Keep in mind dropping and changing URLs may temporarily shift the site in the SEs, this is generally rare and usually will not effect the home page. In this case you may see shifts on the internal pages.
I think a redesign is not likley to have any impact either way (unless you have really messy HTML and you clean it in your design, in which case it could help a bit in the SERPS), but changing file names could have seriuous adverse efefcts. I would avoid changing file names, if possible.
Thanks for the feedback guys.
unfortunately, for various reasons, we have to change the page names and file structure.
With this in mind would you:
a) Change file structure (with 301s) now and then launch new site design in three months
b) Launch site redesign and new file structure (with 301s) all at the same time?
I would upload a batch changes and monitor the effect. Better to see problems in a subset rather than the whole.
I just went through this and believe I made a big mistake by removing the old site pages. After watching my traffic drop to about 20% of where it had been prior to the redesign for over a month, I decided to put the old pages back. Traffic has recovered somewhat but is still way off from where it had been before I made the change. If you can, my advice would be to leave your old site pages as is and introduce the new site in addition to them, not in replace of.
why must you rename the pages?
we have to rename the pages because:
a) last time we redesigned we kept all the old page names to keep PR and possible grand-father effect...it's now very difficualt to establish where you are in the site from the url (plus the page names are terrible from an SEO point of view)
b)they are all in .htm and we are redesigning in asp.net (hopefully we'll then url rewrite so that the page structure looks like [domain.co.uk...]
You should have no problems unless the inner pages rely on incoming links (known as deep linking).
If you are feeding most of them from your internal PR then you'll be fine, just make sure all the old URLs redirect to the corresponding new ones.