Building a Low-Cost Personal Data Center in the Attic

If you are tired of listening to the humming of your computer equipment, looking at the cable mess, and having all that stuff taking up precious space in your office or living space? You are ready for building your personal data center in your attic. Here is a tried solution that works (with some limitations on the maximum power dissipation.)

If you are ready for a larger-scale datacenter in your home, use a bathroom, or for a really large one, a garage.

low-cost Personal data center

The major steps for your attic data center are as follows:

[ ] Find suitable space in the attic for a small server room
[ ] Build a thermally insulated space
[ ] Install ducting and temperature control equipment


We could have chosen an air conditioned room in the house for simplicity, or a closet or garage, but we avoided all of these to keep this completely out of the way and to avoid having to make holes in walls for ventilation.

We needed space for modems, routers, switches, UPS, and two or three servers and external hard discs. Considering the heat management issues it also seemed wise to build larger to increase heat capacity of the room to temper temperature swings. We chose a size of about 6′ x 4′ x 2′. Even this can heat up quicker than you would think.

If you have an easily accessible attic, find a vertical structure to attach the box to in an easy to access location. Mounting on the attic side of an exterior wall should be avoided if the wall gets hot in summer, but it is possible to do so with some additional insulation.

Construction of the datacenter “box”

To keep materials cost to a minimum I settled on “lay-in” ceiling panels, often seen in offices, attached to a strong wooden frame out of 2×4 studs. The ceiling panels are insulating, should have some fire resistance, depending on the material, are lightweight, and are easy to cut and process.

The lay-in panels are not strong enough to carry much weight. Therefore I attached a shelving system to the studs of the back wall.

Between the back of our box, and the wall we attached this box to, we inserted glass wool insulation, and installed rafter vents to allow air flow between insulation and the wall we attached our box to.

We sealed all seems using duct tape, to eliminate air leakage. We also installed an air-tight flexible strip around around the front opening, and hooks to keep the lid tightly shut when not opened for access. Finally, the entire box was wrapped with glass wool insulation.


What seemed simple, quickly turned out to be much more complicated because of the need for managing heat hundreds of Watts of heat dissipation. How do you deal with the summer 100F+ temperatures in an attic in a hot climate? You could buy an A/C system just for your datacenter for hundreds of dollars (and deal with plumbing condensation drains for continuous operation and to avoid floods, and additional noise), but for a small datacenter this may no be necessary.

We found a cost-efficient, quiet and efficient solution to these problems; using your existing A/C and the thermal capacity of your home. The idea is to continuously circulate air-conditioned air from inside the home through the attic datacenter.

Since the power dissipation of all the equipment was around 500 Watts, we could get away with relative little airflow. We purchased a Fantech FG4230 135 CFM, 4″ centrifugal in-line duct fan, and took air in from the A/C and pulled it through the datacenter, and returned it to the A/C nearby. Unfortunately I quickly learned that 135 CFM and 4″ ducting limits the total power dissipation to only a few hundred Watts. Just sufficient for a small server and a couple of routers and such.

In hindsight, something in the order of 600 CFM, and more importantly, higher diameter ducting such as 8″, 10″ or more, would have been a much better choice. However, higher airflow fans tend to make more noise (I know – I am using a Goplus 8″ in-line duct fan for a different project) so some experimentation may be needed to find the right balance and equipment.

Scaling Up

At some point, maybe beyond 1,000-1,500 W, ventilation based cooling must to be replaced by cooling using a dedicated portable A/C. For my bath-room sized datacenter I had to switch to dedicated active cooling. I used a reasonably priced ($400 order) Whynter ARC-122DS Elite 12,000 BTU dual-hose A/C unit to cool about 2,000-3,000 Watt worth of equipment. For even more equipment I had to move to the garage, closer to the breaker panel, and outside air. More on that some day in the future.

The original attic datacenter continues to serve as the home of a UPS, wireless routers, switches, cable modem, and a low-power reliable ZFS file server.

updated: 20170128, 20170217, 20171212; 20180623
photo: (c) Copyright 2017

1 thought on “Building a Low-Cost Personal Data Center in the Attic

  1. pleiades Reply

    please update this post, i would like to make something like this, can you post also how to connect to the server room in the house.

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