Forget about appealing to mass markets
Chairs and toilets both are designed to be used from a seated position, and both are prescribed to be at least 17” above the floor for the most accessible use. But what if they are built closer to the floor – lower? Does this make them inherently unusable? Absolutely not. In fact, many people prefer them to be smaller or lower to match their physical size, abilities, or requirements.
While there is a general standard in sizing, we cannot mandate a certain height from the floor for devices like chairs, beds, and toilets. Some people are comfortable using them at a 17” inch or even more, and many are not. Some people just aren’t tall enough to use them at an elevated height, and some desire them to be 19”-20” or more. As we know about aging in place, everyone is different with varying needs so there can be no pronouncement or universal creation of such items unless they are adjustable – and we are starting to a few of them.
Therefore, as much as we want to find an acceptable standard with mass-market appeal that can be used universally, this is not easily achieved.
Factoring in sensory limitations
Whatever height we choose for sitting (chairs or toilets, for instance) or other areas in the home such as countertops, we know that people have varying sensory abilities that often mean changing what we want to use to what will meet their needs. Needs are subject to change over time as well.
Someone earlier in life may have more flexibility, coordination, balance, leg strength, and visual acuity to where they can find the toilet or chair and sit on it comfortably and easily. As the years go by, this task may become more challenging. Just raising it or making the sitting surface larger isn’t necessarily the answer either.
The point is that each design must meet the needs of the most demanding user in the home – sometimes a design just for them with other members of the family using something different for that particular purpose.
Adjustable height toilets, countertops, tables, sinks, and other items in the home may be a reasonable solution for people with needs that respond well to such changes and accommodations.
Universal design helps
As helpful and useful as universal design is for appealing to most individuals, it may not be the solution for people with more demanding needs or households of disparate needs. Take a family where the adults may have a height differential of more than a foot. Where something is located above the floor for the tallest person likely is too tall for the shorter one, and vice versa. There are accommodations, but there may not be a perfect solution short of having multiple installations in a space to accommodate those disparate needs and abilities. The same would hold true for people operating from a wheelchair versus those who stand to use the space.
We can design pulls, cabinet and counter locations, seating, lighting, switches and controls, appliance locations to accommodate the general user in a universal application, but there might be some people whose height, reach, range of motion, mobility, or visual lie outside the useable and accessible areas of such designs.
Reasonableness should be the guideline
We might be designing for specific individuals using an aging in place approach with a need to accommodate their specific abilities. On the other hand, we might be renovating a space for the use of the people living there now with an eye on their potential future needs or what new occupants might appreciate when the home changes hands. They may or may not have specific abilities that need to be addressed.
On the one hand, we want to meet the specific needs of our clients, subject to what they are presenting to us. In the absence of specific needs other than what might occur through the normal aging process, we can design for the reasonable use of the space.
Wider, unencumbered passageways, lighting that illuminates every part of the walkway areas and other usable spaces (counters, for instance), controls and switches that can be reached from a seated or standing position, windows and doors that require a minimal amount of physical effort and strength to operate, and a solid surface flooring that allows movement across it without much resistance are improvements we can offer than addresses the needs of most individuals that would be considered reasonable.
While designing for an average need or ability is tricky since it is so often non-present or identifiable, we can do things that provide a reasonable amount of accommodation for many people.