Ask HN: How to arrange offices when growing?

Question for those that are in the same situation as we are, probably most of you :-) We've grown from 2 to 15 people and are hiring 3 to 5 more in the next two months. When we went from 2 to 5 we just moved from flex spots to a large rectangular office. While growing we've basically just added 10 more desks so they're all in little islands of 3 or 4 in the same rectangular space.

Of course growing also means we're no longer just a big development-team, but also have account managers, customer support and consultants, which due to many phonecalls etc cause a lot more noise than a bunch of developers with headphones.

So how did others deal with this? We're not big enough yet to get an office with lots of separate rooms. We also really want to keep the collaborative/pairing culture we have in the development team, people move around and share keyboards all the time. But we do need to get them a bit more quite environment somehow, preferably without splitting the team entirely because there is a lot of collaboration.