Rebuilding a site without throwing away your search visibility
Almost everyone who starts on a new site asks the same question: will we lose our place in Google? That fear is justified, because it does happen. Only it is rarely caused by the new site itself.
What causes the drop
The biggest cause is addresses changing without anyone redirecting them. Your old page was at /diensten/webdesign/ and the new one is at /website-laten-maken/. To you that is the same page. To a search engine, and to everyone who ever linked to the old address, the old page has disappeared.
The second cause is texts being thrown away. In a rebuild everyone wants everything shorter and fresher. Often that old text is exactly why you get found, because it contains the words people actually type.
The third is the structure being rearranged on instinct. Three pages become one, or one becomes five. That can be a good choice, but then it is a choice and not a by-product of the design.
Record what you have first
Before anything is built, you need to know what is there. That is an hour of work and it determines the rest.
Make a list of all your current addresses. If there is a sitemap on your site, you already have that list. Note which pages bring in visitors, from Google Analytics or from Search Console. Note as well which pages get links from outside.
That list is your measuring stick. Without it you will not know afterwards whether anything went wrong, and you will not be able to repair it either.
Redirect one to one
Every old page gets a 301, a permanent redirect, to the new page that comes closest to it in content.
What you must not do is send everything to the homepage. That is technically a redirect and nothing more: the visitor lands on a page that is not about their question, and search engines treat it as a page that has gone. You lose everything anyway, just without an error message.
If you cannot find a good successor for an old page, a proper 404 is better than a wrong redirect.
Keep what works
In a rebuild we first look at what is good. The texts are often better than people think, and the structure is usually largely right. What has to go is the technology underneath and the plug-in bloat that has built up over the years.
New technology underneath, familiar structure on top. That is almost always the cheapest and the safest route.
What to expect after launch
A short fluctuation is part of it. Search engines have to crawl your site again and process the redirects, and that takes a few weeks.
A lasting decline is not part of it. If you still see fewer visitors after a month, then something went wrong with the redirects or content has disappeared. With the list you made beforehand, you can trace that in an afternoon.
In that first month, check Search Console under Pages every week. It shows which addresses have been indexed and which have not, and why not.
