Designed By Niels Diffrient

Summa Executive Chair with Upholstered Back Shell

A refined approach to everyday seating. Summa delivers balanced support and lasting comfort in a versatile, streamlined design.

Design Features

  • Red Dot Award-winning design

    Red Dot Award-winning design

    Recognised internationally for its refined executive silhouette.
  • Tailored upholstered back shell

    Tailored upholstered back shell

    Creates a furniture-like finish that blends seamlessly into premium interiors.
  • Self-adjusting recline support

    Self-adjusting recline support

    Weight-compensating mechanism responds naturally for effortless comfort.
  • Minimalist control design

    Minimalist control design

    One discreet height lever keeps the chair intuitive and visually uncluttered.
  • Premium upholstery options

    Premium upholstery options

    Available in Kvadrat textiles and chrome-free leather for an elevated, responsible finish.

Specifications

Variant

SKU

U1ULBAR13XFSSNC

Casters

Multi-Surface Caster for Hard or Soft Floor

Warranty

10 Years; Fabric/Cushions/Arm Pads/Casters: 5 Years

Dimensions

Width

28 in

Depth

25.5 in

Overall Height

36.25 in - 41.25 in

Backrest Height

20.75 in.

Seat Depth

18 in - 18 in

Seat Height

15.5 in - 20.5 in

Weight

Overall Weight

43 lb

Weight Capacity

300 lb

Materials & Sustainability

  • Product Materials

    Summa is constructed using die-cast aluminum, steel, engineered polymers, wood veneer, contoured seat cushion, and upholstery textile. Die-cast aluminum and steel form the structural frame and recline mechanism. Engineered polymers are used for components requiring flexibility and impact resistance.

Who It's For

For people who want an executive chair that feels luxurious and tailored, without sacrificing ergonomic performance.

  • Ideal for executive offices and leadership workspaces
  • Great for boardrooms and meeting spaces where comfort needs to look refined
  • Perfect for architects and designers specifying premium seating for high-end projects

Certifications & Testing
  • DECLARE® - Red List Approved
  • CDPH
  • BIFMA LEVEL® - Level 3
  • SCS Indoor Advantage Gold
  • MID

Care, Maintenance & Longevity

  • Upholstery

    Care instructions vary depending on the selected upholstery. Vacuum regularly using a soft brush attachment to remove dust and prevent dirt from working into the fibers. For spills, act quickly — blot liquids with an absorbent cloth before they set. Stains should be removed by gently dabbing with a lint-free cloth or sponge dampened with clean, warm water. If necessary, add a small amount of mild dish soap, then finish by dabbing with clean water. Avoid rubbing, as this may damage the textile surface. For wool textiles, professional dry cleaning is recommended for anything beyond surface stains. For detailed care instructions by upholstery type, refer to the Humanscale Care Guide.

  • Frame, Base & Components

    Clean metal and plastic components with a soft, damp cloth and mild soap if needed. Dry thoroughly.

An effortless blend of luxury and simplicity.

Summa's versatility takes it from the corner office to the boardroom to the executive home office.

4.3
Rated 4.3 out of 5 stars
Based on 6 reviews
Total 5 star reviews: 3 Total 4 star reviews: 2 Total 3 star reviews: 1 Total 2 star reviews: 0 Total 1 star reviews: 0
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6 reviews
  • Michael C.
    Verified Buyer
    Rated 3 out of 5 stars
    Purchased Summa for my

    I purchased Summa for my home office and it instantly elevated the space. People comment on it every time they visit.

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  • Enzo C.
    Verified Buyer
    Rated 5 out of 5 stars
    Chair feels like it

    This chair feels like it belongs in a Forbes cover shot. The leather is buttery soft, the lines are clean, and it just feels… indulgent. I can sit here for hours and still feel supported.

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  • Yuna Y.
    Verified Buyer
    Rated 4 out of 5 stars
    Enveloping back and integrated

    The enveloping back and integrated arms make it feel like the chair hugs you. Definitely a different level from other executive chairs I’ve tried. Worth the price.

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  • Ryan O.
    Verified Buyer
    Rated 5 out of 5 stars
    Really elegant

    Really elegant, very well made. I love all the color options, but the price increase for leather seems a little unreasonable. Ended up going with a more basic fabric

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  • Alma N.
    Verified Buyer
    Rated 5 out of 5 stars
    Use this for boardroom meetings and it's amazing

    I use this for boardroom meetings and it’s amazing. Big step up!

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