Client / Owner: Withheld
Team Members: Jake Weber, AIA
Contractor: Cornerstone Construction Services
Engineer: KPFF Engineering (Glass Stair), Vista Structural (Entry Bridge)
Landscape: BASE Landscape
Project Type: Remodel
Building Type: Single Family Residence
Location: Portland, OR
Completion Date: 2020
Photography: Speeds Photo
- 2021 Master Design Awards: Silver – Residential Specialty for Glass Stair
GSW/A was brought onto the remodel of this Mediterranean home in the West Hills of Portland, mid-construction and was asked to design the entry sequence including an entry bridge, the entry door, and an architectural stair. Built on a steep hillside, the home had no traditional front yard, so the entry bridge was designed as two separate spaces: an entry walk to the front door, and a terrace for outdoor dining. The entry door is defined by a white frame with flanking white oak benches that appear to penetrate the entry glass. Upon entering, the central stair that traverses all four levels of the home is partially recessed to maintain incredible views of Portland below. The client was looking for a unique, architectural stair on the main level of the home to be viewed as a sculptural element. To maintain a sense of lightness, we designed the stair to be supported on two sides by full height glass panels, with a center plaster wall. Engineering glass to support gravity loads of the stair treads was a unique challenge, and special computer software was used to calculate the loads and specify the glass type. The glass is two layers of 5/16-inch laminated glass with a 0.06-inch SentryGlas layer in between for added strength. Additionally, the glass panels could not take on load from the ceiling they were mounted to, so deflection heads were detailed to allow the ceiling to deflect without loading the glass panel. These deflection heads were recessed metal channels within the ceiling finish and also allowed for the glass panel to be slipped in place.
Installation of the stair was the last piece of construction within the whole-house remodel, and handling of the 9.5-foot tall, floor-to-ceiling glass panels at the end of a remodel project was delicately done. The team designed the wood tread to appear to penetrate the glass with the wood tread revealed on the outside faces of the glass. To limit the holes drilled through the glass, the tread maker fabricated a tread cap with recessed magnets that secured the wood cap in place, magnetizing to the bolt heads used to support the tread in the glass.