O/I design studio is a London based practice working on architecture, interior design and landscape projects. O/I means a state of balance; we pursue a harmonious arrangement that holds every detail of a building together, making it integral from inside out. We actively blur boundaries between space, as well as taking inspiration from architectural history, vernacular traditions, crafts and environment. We address architecture through our unique natural process that adapts contexts and clients' requirements, creatively.

We work with private clients and charitable organisations, in the UK and worldwide. Our projects range from refurbishments, house extensions, artist studios and landscape commissions in London; to larger projects abroad such as a private villa in UAE and a chapel in Taiwan.


Chih-Wei Weng


Chih-Wei (AA Dip, ARB Architect), is a director of O/I Design Studio.

Before founding O/I Design Studio with Esther in 2018, Chih-Wei worked independently on boutique residential, commercial and exhibition projects in London while developing his unique philosophy to design.

Prior to this he worked at the London based architectural practice Squire and Partners and amongst other projects, he was part of the key team delivering Bulgari Hotel and Residences in London.

Chih-Wei graduated from the Architectural Association in London in 2006, where he was awarded the William Glover Bequest for his special contributions to architecture technology.


Esther Weng


Esther (ARB Architect, former European Certified Passive House Designer) is a director of O/I Design Studio.

Esther founded O/I Design Studio with Chih-Wei in 2018. 

Before that Esther worked as Associate Director in London based architecture firm Squire and Partners. During her time in Squire and Partners Esther mainly worked on 5* Hotel and high-end residential projects including Bulgari Hotel and Residences in London, and 77 Mayfair, a prime residential project in central London, where she was the project architect.

Esther graduated from Magdeburg University of Applied Science in Germany in 2008 and in 2014 she studied at the BRE Academy in Watford to become a certified European Passive House Designer.


Yi-Jen Chen


Yi-Jen (AA Dip, ARB Architect), is an architect of O/I Design Studio.

Before joining O/I Design Studio Yi-Jen worked in London based architecture firm Sadie Snelson Architects as an Associate Director. There Yi-Jen specialised in the high-end residential projects and has designed and detailed more than 30 unique residential projects across London. Prior to London Olympics 2012 Yi-Jen has developed competent construction knowledge at John McAslan as one of the on-site architects who delivered King's Cross Station.

Yi-Jen graduated from the Architectural Association in London in 2011. He involved teaching activities thereafter until 2015.


Tayo Arkle 


Tayo Arkle (BA Hons, MArch) is a Part II Architectual Assistant who joined O/I Design Studio in 2020. She has worked on a wide range of projects from High end residential schemes in London Belgravia to Manchester City’s Etihad Studium Expansion. Tayo also gained construction experience working abroad in Lagos, Nigeria and was a part of the education team in her previous office. This involved working with the local community and schools to help make architecture more accessible to under privileged youths.
In her spare time she enjoys cycling, cooking and watercolour painting. Tayo is currently preparing her Part III at Westminster University.