The 875 sq m single-storey building for Southwark council will house the authority's One Stop Shop customer services for up to five years while permanent facilities are developed.
Once its job is done, the free-standing pavilion will then be moved and reused for either 'leisure, community or educational purposes'.
Sat on a former council car park within the Bermondsey Spa regeneration area, the £1.55 million building is covered in a lightweight roof supported on trusses spanning 22.5m.
The building, which was designed in collaboration with Arup, also features triangular ETFE pillow skylights - as used at the Eden Centre - and a subfloor ventilation system.
Speaking about the project, Andy Brown from the council's building design service, said: 'We needed a flagship design that would set a benchmark standard for face-to-face facilities elsewhere in the borough, as well as providing a positive modern symbol of the civic presence in Bermondsey.
He added: 'We needed the building to be relocatable but with a permanent feel.'
The Hammersmith-based practice recently underwent a name change 'in recognition of the key role played by long-standing director Paul Sandilands'.
The all new Lifschutz Davidson Sandilands now employs more than 50 staff.