
The Octagon
47-storey mixed-use tower on a compact central Birmingham site — 370 apartments above retail, redefining the city's residential skyline.

Tall buildings, BTR, mixed tenure and heritage — the country's most ambitious residential programmes.
From Europe's largest CLT residential structure to 47-storey towers over Birmingham's skyline, we have helped deliver more than 10,000 homes. We hold the cost narrative through complex tenure mixes, modern methods of construction, and listed-building constraints.

A representative cross-section of recent and ongoing schemes — more on request.

47-storey mixed-use tower on a compact central Birmingham site — 370 apartments above retail, redefining the city's residential skyline.

Demolition and construction with retail at ground floor.

Two volumetric-MMC residential blocks (354 BtR / 223 DMR) within the wider 2,000-home Greenford Quay regeneration — one of London's largest single-developer BTR schemes.

Tower with 3,700 ft² commercial below.

Four phases mixing affordable and private blocks.

Tower with retail and dock remodelling.

Cinema/bingo conversion with Corten façade.

New build with pool, spa, cinema and resident facilities.

Private and affordable homes with landscaping.

Mixed 1–2 bed in Ladywood with rooftop garden.

Office-to-dementia-care conversion with balconies.

Private residential with ground floor commercial.

Two blocks with retail and basement parking.

Two buildings with commercial and amenity space.

Net Zero target, canal-adjacent public realm.

HQM 4.5-star target, rooftop garden amenity.

Mixed office refurb, low-rise and mid-rise residential.

Europe's largest cross-laminated timber residential structure — 121 units of PRS and affordable housing demonstrating CLT's potential at scale in London.

Grade II listed amalgamation and refurbishment.

Grade I listed redevelopment with mews house.

City-centre tower block.

Brownfield redevelopment retaining MG buildings.

“Berkeley Homes and Argent / Hermes are among the institutions reshaping residential — Quantem's role is to underwrite the numbers behind it.”

Landmark new-build, refurbishment and CAT A/B fit-out for the institutional London office market.

CAT A and CAT B workplace delivery — from boutique floors to 370,000 ft² institutional schemes.

Cluster, studio, listed and high-rise — purpose-built student schemes from 75 to 1,435 beds.

Flagship, big-box, market and airport — retail environments built for footfall and brand.
From RIBA 0 viability to final account — our partners are ready to take the call.