Planning a Small Business Server Room: Location, Power, Cooling and Security (or Skipping It Altogether)

A server room is a small room with expensive requirements. It needs a location nobody wants for anything else, clean power that does not fail when the building’s does, cooling that runs every hour of every summer weekend, physical security, fire protection and enough space that the next server does not go on the floor. This guide, which combines our two earlier articles on server room planning, covers each requirement, what a proper room costs, and the question that has changed since we first wrote it: whether a small business should house its own servers at all, now that a local data center will do it for a flat monthly fee. Our article on the three types of servers explains the options; this one is about the room.

1. Location

Choose an interior room with no windows, away from water: not below a bathroom, next to the water heater or under the roof drain. Central to the office reduces cabling runs, and cabling has limits, so a long thin building may need a second closet for switches. Avoid spaces that will be reclaimed when the business grows; the server room that becomes an office moves the servers into a hallway. Low foot traffic and a door that can be locked are the minimum. If the only candidate is a closet with no ventilation, skip to the last section.

2. Power

Servers need dedicated circuits, not a shared outlet with the copier. A small rack draws 1,000 to 3,000 watts; plan the circuits with an electrician and label them. Every device in the room, including the switches, the firewall and the internet provider’s equipment, goes on an uninterruptible power supply that bridges short outages, filters the bad power common in older buildings and gives the servers time to shut down cleanly in a long one. Size the UPS for 15 to 30 minutes and put it on the monitoring system so a dying battery is a ticket rather than a surprise; batteries last three to four years. A business that cannot afford any downtime adds a generator or, more sensibly, moves the servers to a facility that has one.

3. Cooling

Nearly every watt a server draws becomes heat, so a rack drawing 1,500 watts needs about 5,000 BTU per hour of cooling, all the time. Building air conditioning that follows office hours is the most common cause of the summer failures we see: the room reaches 100 degrees on a Sunday afternoon, the servers throttle or shut down, and Monday starts badly. A dedicated cooling unit, either a ductless split system or a portable unit vented properly, keeps the room at 65 to 80 degrees around the clock. Add a temperature and humidity sensor that alerts someone, and arrange the rack so cool air enters the front and hot air leaves the back rather than mixing.

4. Physical security

A locked door with a keypad or badge reader, so access can be given and revoked without changing locks and a record exists of who entered. No windows. A camera on the door if the business handles regulated data, because HIPAA, PCI and SOC 2 all ask who can reach the equipment. Visitors, cleaners and contractors do not enter unescorted. The room is not also the storage closet for paper towels, which is how doors end up propped open.

5. Fire, water and monitoring

A smoke detector connected to the alarm system, a clean-agent extinguisher rather than water or dry chemical, no water pipes overhead where it can be helped, and a water sensor on the floor where it cannot. Environmental monitoring, temperature, humidity, power and water, costs a few hundred dollars and pays for itself the first time it sends an alert on a holiday weekend.

6. Rack, cabling and space

A four-post rack for servers, with room to work behind it, which is the usual failure in small rooms. Structured cabling terminated on patch panels rather than long cables run to the switch, labelled at both ends, with a documented map. Space for twice the equipment you have, because the room will not move when the business grows, and a shelf for the things that accumulate: the backup appliance, the phone system, the spare parts.

What it costs

A basic room therefore runs $8,000 to $20,000 before a single server, plus the running costs, and it needs an owner: someone who replaces the UPS batteries, changes the filters, watches the sensor and keeps the door shut.

The alternative: do not build one

When this article was first written, a growing business built a server room because there was no alternative. There is now. Colocation puts your own servers in a data center built for them, with redundant power and generator backup, cooling designed rather than improvised, monitored security and engineers on site, for a flat monthly fee based on the space and power you use. For most workloads that still need a physical server, the building it sits in makes no difference to the people using it, and the office keeps a switch, a firewall and a UPS in a small cabinet. Over five years, colocation often costs less than the room above, and it removes the summer-weekend failure entirely. Our server hosting and colocation page describes the arrangement in our own Minneapolis data center, and getting rid of your server and moving to the cloud covers the workloads that do not need a physical server at all.

If you keep the room

Under a managed IT plan the room is part of what we monitor: UPS status and battery age, temperature and humidity, the door sensor if there is one, and the servers themselves. The server support page covers the ongoing side, and the pricing calculator gives the monthly figure. Whichever you choose, the servers need the same backups somewhere else; the backup pricing calculator covers that.

Common questions

How big does a server room need to be?

For a small business, a closet of about 6 by 8 feet holds a two-post or four-post rack with room to work behind it, which is the usual failure: racks pushed against walls with no access to the back. Plan for double the equipment you have today, because the room will not be moved when the business grows.

How much cooling does a server room need?

Roughly the electrical load of the equipment, since nearly all of it becomes heat: a rack drawing 1,500 watts needs about 5,000 BTU per hour of cooling, running continuously, including weekends and holidays. Building air conditioning that shuts off at night is the most common cause of server failures we see in summer.

Do we need a UPS?

Yes, on everything in the room: servers, switches, firewall and the internet equipment. A UPS bridges short outages, filters bad power and gives servers time to shut down cleanly in a long one. Size it for 15 to 30 minutes of runtime and replace its batteries every three to four years.

What is the biggest mistake?

Putting the servers in a space that was never meant for them: under the stairs, next to the water heater, in a closet with no cooling, or in an office that gets repurposed. The second biggest is nobody being responsible for the room, so the UPS batteries die, the filters clog and the door is propped open.

What does a proper server room cost?

A basic small-business room with a rack, a UPS, a dedicated cooling unit, a keypad lock, cabling and a monitored sensor typically runs $8,000 to $20,000 before the servers, plus electricity and maintenance every year. Colocation in a local data center is a flat monthly fee for space and power and often costs less over five years.

Should we just put the servers somewhere else?

If your office cannot give them clean power, continuous cooling and physical security, or if you would rather not own the problem, yes. Colocation keeps your own hardware in a facility built for it, with engineers nearby, and most workloads that need a server do not care which building it is in.

Talk to us

If you are planning a server room, or your current closet is too warm, we will look at the space and the equipment and tell you whether to build, fix or move it, with a price for each. Call 952-548-5558 or contact us; the first conversation is free and there is no long-term contract.