Keep in mind that the sizes given below are only a rough guide to the kind of portable toilet trailers available, as different suppliers tend to tweak their individual models, though they do all follow the same basic patterns.
As its name suggests, single stall restroom trailer sizes tend to represent a fairly small specimen, one which contains only a single toilet. On average they range from around 12 – 14 foot in length, and 8-9 foot in width. Some of the larger versions will have separate urinals installed as well as a standard toilet.
Double stall trailers are identical to their single stall cousins, except as they hold two toilets instead of one. Often these toilets are clearly separated but share sanitation facilities. As a result they aren’t much larger than single stall units, coming in at around 15-17 foot long, 11-13 foot wide.
Triple stall toilet trailers are once again only slight bigger than the double units, housing three toilets instead of two. They come in at 20-22 foot long, 11-13 foot wide. These units are more likely to allow for properly segregated individual toilets than their double stall counterparts, acting as a private uni-sex environment in which each stall has its own washing facilities.
With ten stall units, the restroom trailer sizes tend to grow to be at least 28-30 foot long and around 12-14 foot wide. These toilets normally come in two blocks, one for each of the sexes, with the male stalls normally including urinals at the expense of actual toilets.
Two Stall with Disabled Access
The two stall trailers with ADA access actually provides three toilets, though one is only supposed to be used by people who have difficulties with stairs or who need help whilst visiting the facilities. These type of toilet trailers come in at 23-25 foot long and 13-15 foot wide.