Deconstructions: Sittris Siliform Chair

Helen Kerr’s innovative line of health-care seating is soft, airy, and germ-resistant.

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Silicone rubber is indispensable in the design of medical products. Cheap and pliable, it is also by nature hypoallergenic, chemically inert, and germ-resistant. For years it has been employed in a variety of small-scale equipment, from catheters to baby-bottle nipples. Now Canadian designer Helen Kerr, of Kerr and Company, has found a bigger application for it: furniture.

When Kerr began designing seating for the health-care market in 2003, she wanted to address an often overlooked problem: patients getting infections from germ-infested furnishings. After considering various antimicrobial materials, she developed, with the help of Toronto-based company Sittris, a method called Siliform for applying silicone as upholstery. “We had done previous work in housewares using silicone,” Kerr says, “and we knew it was inert and easy to clean, so we said, ‘What if we took that material and actually made it the entire surface?’ ”

The result is a line of seating for Sittris with a modern sensibility uncommon to hospitals and clinics. With a variety of arms and bases, the chairs can be configured for a range of uses—exam rooms, waiting areas, and cafeterias—and accomodate users up to 350 pounds. (Kerr has also designed a bariatric version for obese patients up to 700 pounds that is not yet available in silicone.) Here the designer takes us through the finer points of her Siliform chairs.


Holes in the seat pan and backrest provide ventilation and allow any fluid matter to fall through.

The centerpiece of the series is the seat shell, which comes in a mid or low back. Then there’s a whole series of leg configurations; every time the shell is put on a different leg the pitch of the chair changes.

We wanted to take away as much of the backrest as we could to give health-care workers better access to the patient. Much of the treatment in hospitals happens around the torso. When caregivers go to lift or bathe a patient, they can reach the back of his or her body easily.

The material is soft—it actually feels like skin—which is a bonus if you have to sit on your bare bum.

The cast-aluminum leg allows a seat position that is a bit more relaxed for situations where you might be sitting longer—for example, beside a patient’s bed or in a treatment area. The arms for this chair are either flared and covered in silicone or aluminum and looped.

The inside is sculpted foam covered in plastic. The silicone upholstery fits around the plastic layer like a shower cap, and the two pieces snap together with clips, which makes the chair easy to disassemble. The silicone actually works like a gasket to prevent liquid from getting inside.


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