A Guide to Calculating Space Use for Timetablers

A few relatively simple sums can give you clear answers, and in turn help you make the best timetabling decisions! 

Here we’re going to show you how to calculate a room’s frequency, occupancy and utilisation rate. All three can help you spot general patterns of room use without having to wait for bigger space utilisation surveys to be carried out.

Say, for example, you want to gain a clearer picture of space use in a specific building over a certain period of time. You can apply the formulae we’re about to take you through to pretty much any situation. 

Once you’ve got a grasp of these you’ll find them really useful – after all the more understanding you can glean about how a space is used, the better your timetables and in turn, the better the experience for staff and students all-round.

So grab your calculator, and let’s take a walk through calculating frequency, occupancy and utilisation, step-by-step.

Here we’re going to show you how to calculate all three for one room over the course of a week.

Just a side note before we start too - whenever you carry out this exercise, make sure you collect all your data on a room or space over the same time period, to get an accurate utilisation rate figure at the end.

Let’s assume your room is available from Monday to Friday, between 9am and 6pm.

To calculate your room’s frequency rate, simply divide the number of hours it’s available (in this case 45) by the number of hours it’s actually used. Let’s say your room is in actual use for 30 hours of the week. You therefore calculate your frequency rate like this:

You now know your room was used 66.67% of the time and was empty 33.33% of the time. Your frequency rate is 66.67%.

Now you need to figure out your occupancy rate. You’ll need three pieces of information to calculate this:

1. Your room’s capacity
2. The number of times your room was occupied over the course of the week
3. The number of hours your room was in use

Your room’s capacity is simply the number of people who can comfortably use it at any one time, taking into account allocated desk space, furniture and the overall layout.

Let’s assume your room has 20 seats and 20 desks. Therefore, your capacity is 20.

To work out how many times your room was occupied over the course of the week, do a headcount every time the room is used. At the end of the week, you should end up with a total figure - i.e. the total number of times people were recorded as occupying the space. Let’s say this figure is 445.

Now for some more maths! You need to divide your occupancy figure (445) by your capacity (20) x the number of hours your room was actually used (which you know to be 30 hours, from when you worked out your frequency rate). Like this:

You now know that when your room was used it was 74.17% occupied, and that 26.83% of its capacity wasn’t being used. Your occupancy rate is 74.17%.

Now you can calculate your utilisation rate. And it’s super simple - all you do is multiply your frequency rate (66.67%) and occupancy rate (74.17%). Like so: