The Longley Place project is a build-to-rent scheme funded by Legal & General. The development, set around a landscaped podium deck, comprises four blocks ranging from 11 to 20 stories.
Located on an industrial site in close proximity to the rail station, the development – built on a sloping site – offers two sub-levels provided by means of a retaining wall which varies in height from 4.5m to 2m. Temporary works wall solution considers sheet piles ground-anchored to free up activities in the heavily constrained site, subsequently replaced by a reinforced concrete retaining wall in the permanent case.
Lowest slab level is home to various plant, back of house and car-parking facilities, whilst the two floors above deliver two levels of office space. Circa 200 residential units are located in the remaining upper floors, catering for a range of bedroom number formats and tenure types.
Key Technical Challenges
- Basement wall retention system using ground anchors
- Perimeter columns protruding past slab edge as part of masonry faced detail
- Determination of weak spots in chalk substrate
- Careful co-ordination of BWIC on Level 1 transfer slab
Key Innovation
Early detailed slab design attracted savings in slab thickness, thus allowing for additional floor and helped reduced the number of columns.
Sustainability
- VE to perimeter columns – reducing costs of support bracketry and reducing internal columns
- Upon appointment, RBG reduced slab thickness by 20%
RBG Value Add
- Upon appointment, RBG reduced slab thickness by 20%
- Added one floor to blocks
- VE to perimeter columns – reducing costs of support bracketry and reducing internal columns
- Additional fees should have been sought for four month programme prolongation due to delay in getting contractor in contract.
- Rebar fees from work share partner grossly underestimated; get partner to determine no of sheets and commit to paying for own mistakes.
- Know contractor’s preferred format for rebar schedules, e.g. separate column lifts
- MEP engineer tender design was not to high standard; abortive costs leading to Civils redesign
Project Metrics
Project Value:
£80 Million
Year Completed:
Anticipated 2022
Sectors:
Residential
RBG Client:
Legal & General
Project Metrics
Services Engineer:
Hoare Lea
Architect:
EPR
Robert Bird Group Services:
Structural Engineering
Civil Engineering
Geotechnical Engineering
Construction Engineering
Project Metrics
Environmental Performance:
• BREEAM Excellent
• HQM Four Star