100 Pall Mall

100 Pall Mall

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  • location

    100 Pall Mall, London SW1Y 5NQ

  • client

    Motcomb Estates

  • total area

    563 m²

  • system

    CAM—V

  • completion

    2025

Project Overview — The Building

100 Pall Mall is a boutique office building positioned opposite St James’s Square, combining period character with a contemporary workplace specification. The building is undergoing a carefully considered refurbishment programme, delivered in phases as floors become vacant, allowing the asset to evolve while remaining operational.

The 3rd floor forms the second phase of this wider refurbishment, following the earlier completion of works to the 1st floor. The largely column-free 563 m² floor benefits from excellent natural light through historic windows and generous floor-to-ceiling heights, and has been refurbished to an exceptional CAT—A standard. The space is designed to offer future occupiers flexibility, efficiency and comfort, while respecting the architectural qualities of the original building.

Phased Delivery & Partial Occupation

A key challenge on the 3rd floor was the presence of an existing tenant occupying approximately one quarter of the floorplate at the time of works. As a result, building services installations had to be designed, installed and commissioned across the remaining three quarters only, while still aligning with the long-term refurbishment strategy for the building.

In addition, the phased nature of the redevelopment required systems that could support immediate CAT—A delivery, while remaining compatible with future CAT—B fit-out once the floor becomes fully available. This demanded a highly adaptable solution capable of responding to non-standard layouts, partial occupation and future change, without compromising performance, spatial quality or programme certainty.

The AET role

AET was appointed to deliver underfloor air conditioning to the 3rd floor, developing on its previous involvement within the building as part of an earlier refurbishment phase. AET’s return reflects the scalablity and proven performance of the system and its suitability for phased, floor-by-floor delivery.

The 563 m² floor is arranged into three independently controlled zones, each served by a CAM—V33 unit and 16 slimline TU3 Fantiles™ units. Supplied by chilled water and low-pressure hot water, the system provides an efficient and adaptable solution capable of operating within a partially occupied floorplate while remaining fully compatible with future CAT—B works.

Versatility Built In

By removing ceiling-based services, our underfloor system preserves floor-to-ceiling height, maximises natural daylight and allows complete freedom at fit-out stage. The result is a discreet, bespoke and future-proof solution that demonstrates AET’s versatility in responding to complex refurbishment constraints.

Project partners

Developer — Motcomb Estates
Architect — Trehearne Architects
Main Contractor — Virtus
M&E Consultant — Karsons Consulting
M&E Contractor — Gloster S-Worx Ltd

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