Getting the portable office cabin size right is the single decision that affects cost, daily comfort and future resale more than anything else. Order too small and you are buying a second cabin within a year. Order too large and you are paying for floor area, transport and cooling you never use.
This guide gives you a simple way to arrive at the right size before you ask anyone for a price.
Start with people, not with feet
Most buyers begin by naming a size — “give me a 20×20” — when the real starting point is how many people will sit inside and what they will do there. A rough planning figure used across site offices is 20 to 30 sq ft of floor area per seated person once you allow for a desk, a chair and walking space. Add area on top for anything that is not a person: a meeting table, a document cupboard, a drawing table, a pantry corner, a toilet.
Common sizes and what they comfortably hold
| Size (ft) | Floor area | Comfortable for | Typical use |
|---|---|---|---|
| 10 x 10 | 100 sq ft | 2–3 people | Small site office, supervisor cabin, shop cabin |
| 10 x 20 | 200 sq ft | 5–7 people | Site office with one cabin partition |
| 20 x 20 | 400 sq ft | 12–15 people | Project office with cabin, meeting area and toilet |
| 30 x 10 | 300 sq ft | 8–10 people | Long narrow plot, or office plus store room |
| 40 x 10 | 400 sq ft | 12–14 people | Boundary-wall layouts, labour accommodation |
These are comfortable numbers, not maximums. You can seat more people in the same area, but circulation gets tight and air conditioning struggles.
Shape matters as much as area
A 30×10 and a 20×15 both give you 300 sq ft, but they behave very differently. A long narrow cabin is easy to place along a boundary wall and easy to divide into a row of rooms, but the middle rooms get no cross ventilation. A squarer cabin gives better light and airflow but needs a wider clear patch of ground and more room for the truck to manoeuvre. Check the shape of the space available at your site before you fix the dimensions.
Plan the partitions before you order
Internal partitions are far cheaper to build during manufacturing than to add later. Decide up front:
- How many closed cabins do you need (project manager, accounts, store)?
- Do you need a meeting or drawing room?
- Is a toilet or pantry going inside the cabin, or coming as a separate unit?
- Where will the entrance door sit, and will people walk through a working room to reach the back?
A simple hand sketch with room names and approximate sizes is enough for a manufacturer to work from — it does not need to be a CAD drawing.
Transport limits you should know
A cabin has to reach your site on a truck and come off it. Very wide single-piece units need special permissions and larger vehicles, which adds cost and delay. Beyond a certain width, cabins are normally supplied as multiple units joined at site instead of one piece. If your gate is narrow, if there are low cables on the approach road, or if a crane cannot be parked, say so early — it changes the recommended size, not just the price.
Leave room for what comes next
On most projects the office grows. A second engineer joins, a store gets shifted inside, a client visit needs a meeting corner. Two practical habits help: order the next size up if the difference in cost is small, and place the cabin so that a second unit can be joined to it later on one side.
A quick checklist before you request a quote
- Number of people who will sit inside daily
- Number of closed cabins and their approximate sizes
- Whether toilet and pantry are inside or separate
- Available ground space at site — length and width
- Gate width and truck access
- Delivery PIN code
With those six answers, a manufacturer can give you a firm size recommendation and an itemised quotation instead of a rough number. Our complete portable cabin guide covers panel types and build quality once the size is settled.
MK Portable Cabin builds office cabins, security cabins, site cabins, shop cabins, container cabins and portable toilets, and has delivered to 300+ clients across India.
Send us your site details for a size recommendation and quotation