New Office : Office Size?
Our company is investigating setting up shop in a (for us) large office (12,000 sq ft). We have present needs for 6 core workers and perhaps two administrators. Long term needs over 4 years are difficult to determine (and by then we would likely lease the remaining 12,000 sq ft on the floor) but may be approximately 25 - 30 total workers (24 core + 6 admin).
New office new space issues
According to the fellas who wrote Peopleware, you need about 100 square feet of space per person. So if it's a one person officel, 10' x 10'. A two-person office, 14'x 14', and so on.
Look at the furniture. I'm betting that you'll be purchasing the same set of furniture for every office. So figure out several layouts you like. Pick the desk, See how it fits in the room. Add a bookshelf or two. Measure for big desks if you may need dual head computers.
Why don't you create a Mock office, and like Mike suggests, plug in your furniture , get a feel for things.
As a software developer, I have found that about 120 sq ft (say 10' x 12', but I have been in some odd shaped rooms, too.) works out quite well. This is plenty of room for a desk, computer table, file cabinet and book shelves. There is also enough extra room for an work table for equipment if you're integrating some hardware, or you'll have a little space for meetings with one or maybe two other people.
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