The Art of Designing Restroom Floor Space

The Art of Designing Restroom Floor Space

When it comes to architectural design, every square inch of space matters. Simply put, “empty space” costs money, so it’s worth looking into whether that empty space is worth your precious dollar or not. For customers who just want things to be economical, keeping empty space to a minimum is ideal.

At a minimum, your restroom must meet ADA standards. The Americans with Disabilities Act (ADA) mandates specific clearances, features, and dimensions to accommodate people with disabilities. From grab bars to hand dryers, baby-changing tables to waste receptacles, every feature the customer wants must be carefully integrated while still adhering to ADA standards.

It should be noted that some customers will not want a purely minimized floor plan. A roomier restroom might be desired for increased comfort or for aesthetic purposes. If your goal is to win the Best Restroom Award with things like furniture or potted plants, then you will want extra space for that.

Each additional square foot not only increases the cost of your building but can also impact shipping costs substantially.

For calculating the extra cost in construction, the rough calculation for increasing the square footage is half the cost per square foot of the building. A building with a cost of $800 per square foot normally would cost roughly $400 per square foot if the blueprint were expanded, etc.

For shipping, the increased size may or may not increase shipping cost. Shipping costs are determined by a set of parameters (height, width, weight). For example, if a shipment exceeds a certain width, it would legally be required to have an escort vehicle travel behind it. A shipment over a certain height would have to detour to avoid certain underpasses, and a shipment with more weight has less transport fuel economy. There are parameter breakpoints that are important to factor, going above them can increase shipping costs by up to five figures.

Ultimately, the decision the customer makes will be about trade-offs. Perhaps you prefer a roomier restroom. The point of this article is to make people aware of the fact that floor space costs money, and that the building might have more floor space than it needs. If you don’t want to pay more than you need to, and want to lower your costs, here are some ways to do that:

Smart Lengthening

A creative solution to save on shipping costs is to elongate the restroom instead of widening it (for restroom models that allow for such modifications). Shipping expenses are generally determined by building width, so if you can create extra space without increasing the building width, that is a shipping cost win.

Additionally, any created space, whether by shifting building dimensions or removing fixtures, creates added flexibility for the architect to design a floor plan that has the smallest possible amount of wasted floor space. Fewer complications = more optimization.


Pros: Potentially reduce expense for building and/or shipping expense

Cons: A rectangular building may not look as good as a square building or easily fit into a tight space


Intelligent Cabin Distribution

Meeting ADA standards means using up space you otherwise wouldn’t have to. One way to reduce space is to design a restroom with one ADA-compliant cabin and one non-ADA, since only one ADA-compliant cabin is required by law.


Pros: Reduce expense

Cons: ADA cabins and stalls are spacious and more comfortable for everyone, not just people with disabilities


Relocating Sinks

A simple way to reduce your floor plan footprint is to move the sinks outside.


Pros: More space / flexibility. Outdoor sinks can be useful in areas where sink use is needed independent of bathroom use (beaches, playgrounds)

Cons: Not able to wash hands before exiting, a restroom without a sink might seen aesthetically unusual.


Outward-Swinging Doors

Doors that swing outward are a clever way to conserve indoor ADA clear space. This design choice can prevent congestion near the entrance while also providing more flexibility for layout configuration.


Pros: More space

Cons: None


Downsizing Mechanical Rooms

Mechanical rooms are essential, but they can take up considerable space. In models like Sundance or Salish, opting for a mechanical chase instead of a dedicated room can help reclaim precious square footage.


Pros: More space

Cons: Your maintenance workers might appreciate the extra room to work with


Lastly, we’d like to make one potential recommendation that actually increases the size of your restroom:


Storage rooms

This technically doesn’t save you restroom space, but it might still save you money. In some cases a restroom can be made to have a storage area between the two main restroom compartments. This storage area means you won’t have to own or commit space to a storage shed elsewhere. Since it is part of a prefab building, it will likely be built of much stronger and heavier materials than a typical storage shed, which will matter if you have extreme weather or flooding concerns.


Pros: adds significant utility to your restroom, especially in extreme weather areas.

Cons: increases the size of your restroom