# Custom data center containment: how to adapt it to existing racks

_Published: 2026-11-12_

- Page: https://citadexrack.es/en/blog/cerramiento-de-cpd-a-medida-como-adaptarlo-a-racks-existentes

When a server room grows in phases, it is common to find racks from different brands, heights, and widths. Sometimes there are also empty positions left for future expansion, or there is limited space to open the aisle doors. Can a **data center containment system** be installed without starting from scratch? Yes, but it must be designed from the actual room layout.

At Citadex we supply [hot aisle and cold aisle containment systems for data centers](https://citadexrack.es/es/productos/soluciones-datacenter/cerramientos-pasillo-frio-calor-para-cpds). Our work starts with the dimensions of the site and the equipment layout: the objective is to better separate air flows without losing access to operate and expand the installation.

## What a cold aisle or hot aisle containment system solves

In a standard layout, the fronts of the racks face the cold aisle and the rears discharge into the hot aisle. The containment system helps limit mixing between both air flows. To achieve this, it is not enough to place doors at the ends: the ceiling, the spaces between cabinets, height differences, and the positions where there is still no rack must also be reviewed.

Containment is part of the thermal design of the data center. Savings or final temperature cannot be promised with a universal figure: they depend on the IT load, the cooling system, and the operation of the room.

## How to adapt the containment system to already installed racks

**Racks from different brands and dimensions.** A custom solution can be designed with a self-supporting structure, so the containment system does not depend on being fixed to all existing cabinets. Before fabrication, widths, heights, door positions, maintenance access, and interfaces with the room are checked. Compatibility is confirmed for the models and dimensions in the project.

**Different heights in the same row.** If a cabinet is lower than the rest of the row, a top gap remains through which air can circulate. Adjustment panels designed for that difference allow the gap to be closed. The ends of the row and any nearby obstacle close to the ceiling must also be reviewed.

**Free positions for future growth.** Leaving a footprint without a rack and without closing it breaks the aisle separation from day one. Blind panels can temporarily occupy those positions. If they are expected to be replaced by cabinets later, it is advisable to define from the initial design the reserved width and how each panel will be removed.

**Doors constrained by available space.** A double sliding door may be suitable in one room and may not fit in another. Depending on the available opening path, single-leaf sliding doors or different configurations can be considered. The opening type, clearance, access control, and integration with security systems must be defined in the project.

**Ceiling and fire protection.** In a cold aisle, a ceiling with [Drop Away panels](https://citadexrack.es/es/productos/soluciones-datacenter/paneles-techo-drop-away-para-pasillos-cpd) may be considered, according to the planned fire protection solution. Its selection and integration require validation by the project manager; the ceiling should not be chosen based solely on aisle width.

## When the racks also need to be modified

The containment system may reveal other needs: an existing door that should be replaced, a cable entry that must be sealed, or a new rack that must be integrated into the row. Citadex can assess custom-made doors and elements for existing cabinets and supply [server racks](https://citadexrack.es/es/productos/armarios-rack-server) when the project includes new positions.

For demanding loads, the [Citadex QL Rack](https://citadexrack.es/es/productos/rack-ql-citadex/rack-ql-citadex-maxima-capacidad-y-ventilacion-para-entornos-server-exigentes) offers a declared capacity of up to **1,500 kg of static load**, ventilated doors, large cable entry points, and a No Return system. The model selection, effective load, and its connection to the containment system are verified with the equipment to be installed.

## What we need to prepare a proposal

Send us a floor plan or sketch of the room, general photographs, dimensions and rack models, positions that will remain free, obstacles, access routes, and cooling data. Also indicate whether the data center must remain operational during installation and what expansions are planned. With that information, we can assess the aisle type, its closures, doors, ceiling, and the necessary adaptations.

**Your data center does not have to be a perfect row to assess a containment system.** [Contact Citadex](https://citadexrack.es/es/contacto) and we will design a custom proposal for the racks and the space you have.