Office towers

How does Office towers work, step by step?

1. 1

   Step 1: Set the security strategy with the design team

   The security consultant and the client set the strategy for the building: which areas are covered, how the security systems relate to one another, who will operate them and how the building is expected to function day to day. That strategy drives the space requirements, the network provision and the control room, all of which are architectural and services decisions. It is written down early, because everything that follows is coordination against it.

2. 2

   Step 2: Define the interfaces in writing

   The designer sets out what must integrate with what - access control events, intercom, the building management system - and to what depth. Each interface is then assigned to a contractor with a defined responsibility boundary, an agreed method and a date for proving it. On a large project this is a schedule that is reviewed at every progress meeting. Interfaces that are described only in general terms in a specification are the ones that fail, because each contractor reasonably assumes the other side is doing the work.

3. 3

   Step 3: Coordinate comms rooms and structured cabling

   Cabling forms part of the structured cabling installation, so the camera positions and their cable requirements are included in that design rather than added later. Each floor's comms room needs the space, containment, power and cooling to take the security equipment as well as everything else, and that has to be reflected in the room layouts. Cable route lengths are a design constraint the cabling designer works to, so positions that sit a long way from a comms room are identified early and served accordingly.

4. 4

   Step 4: Install containment with the services package

   Containment is installed with the wider services as the floors progress, coordinated in the ceiling void with mechanical, electrical, sprinkler and lighting installations, and taken through fire compartments with the correct sealing. Positions in feature areas such as the reception and the lift lobbies are agreed with the architect at design stage so the fixings, ceiling details and finishes are built in. Fitting these out after the ceiling grid is complete produces exactly the compromises the client will notice first.

5. 5

   Step 5: Build the head end and the control room

   The recording and management platform sits in a controlled equipment space with the power, cooling, network and access arrangements the design specifies. The security control room is a separate item: a working space for operators, with sightlines, display arrangements, communications, and its own environmental and access requirements. Both are architectural and services deliverables that need to be fixed on the drawings early, because both are frequently squeezed when space is under pressure late in the design.

6. 6

   Step 6: Terminate, configure and prove each floor

   Positions are mounted, terminated back to the floor comms room and proved through to the head end. Fields of view are set on site with the security consultant, because the fit-out layout rarely matches the coordination model exactly. Each floor is recorded as complete with a written result rather than a verbal confirmation, since on a tower there will be dozens of floors and nobody will remember which ones were proved.

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   Step 7: Prove the integrated system, not just the parts

   Once the contributing systems are installed, the interfaces are tested as a whole: an access control event producing the associated recorded image, the building management system receiving what the design says it should. Testing is witnessed by the design team and the client's security manager and recorded against the interface schedule. This is the step where systems that were each installed correctly still fail, because integration only exists once it has been demonstrated.

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   Step 8: Commission in phases against the occupation programme

   Commissioning is planned around handover dates, not around the end of the project. Each floor or zone is commissioned, witnessed and handed over as it is released, while construction continues elsewhere in the building. That means repeated mobilisations, temporary arrangements at the boundary between live and construction areas, and careful control of who has access to what. The programme allows for it explicitly, because compressing phased commissioning is how buildings get occupied with security systems that are not finished.