Server Rack Acoustic Foam: Acoustically Treating Server Rooms
Server rack acoustic foam is fire rated sound absorbing foam fitted to the solid panels of a server cabinet and the walls of a server room to cut the fan noise that reflects around the space. It absorbs high pitched fan whine best and must be kept clear of the cooling airflow, because foam also holds in heat. GB Foam Direct supplies Fireseal Class 0 acoustic foam sheets and black self-adhesive Class 0 acoustic tiles, made for enclosures and rooms where fire performance matters.
Key takeaways
- Acoustic foam on server racks and server room walls absorbs high pitched fan noise, but does not block sound through walls or stop low hum.
- Fireseal acoustic foam is Class 0 (BS 476 Parts 6 and 7), Euroclass B-s1,d0 (EN 13501-1) and UL94 V-0.
- Fireseal has a weighted absorption coefficient (αw) of 0.30 at 12mm, 0.45 at 25mm and 0.75 at 75mm, according to GB’s product data.
- Never cover perforated doors, vents or fan trays, because foam is a thermal insulator and blocks cooling airflow.
- Fireseal sheets are 200cm x 100cm in 1/2 inch, 1 inch and 2 inch thicknesses, with self-adhesive sheets in 1 inch and 2 inches.
- GB Foam Direct has converted foam in High Wycombe since 1976 and works to ISO 9001.
What Is Server Room Acoustic Treatment?
Server room acoustic treatment is the use of sound absorbing materials on cabinets, walls and ceilings to reduce the fan noise that builds up in a room full of IT equipment. Hard surfaces such as steel racks, plasterboard and concrete reflect sound, so noise bounces around and the room gets louder than the equipment alone.
Treatment works at two levels. Lining the solid panels of each server rack absorbs noise close to the source, and lining the walls and ceiling of the room absorbs what escapes. In a small comms cupboard next to an office, both together make the biggest difference.
Absorbing sound is not the same as blocking it. Foam reduces echo and reflected noise inside the room, while stopping sound reaching the next room needs mass and sealed gaps. Our guide to acoustic foam for soundproofing explains the difference in more detail.
Does Acoustic Foam Work on Server Racks?
Yes, acoustic foam on server racks reduces the noise that reflects inside the cabinet and leaks out through solid doors and panels, but it will not make the equipment silent. It is most effective on the high pitched whine of small, fast server fans and power supply fans.
Thicker foam absorbs lower frequencies. Our guide to acoustic foam shape and thickness explains why deeper foam is needed for lower sounds. Inside a rack there is usually only room for 1 inch or 2 inch foam, so deep hum from large plant fans or air conditioning units is better tackled on the room walls or at the source.
Foam also does nothing for vibration passing through the frame. Rattling blanking panels, loose rails and fans vibrating against steel need tightening or rubber mounts, not foam.
Where Should Acoustic Foam Go in a Server Room?
Acoustic foam should go on the solid surfaces that reflect noise towards people: the solid side panels and doors of racks, and the walls and ceiling of the server room. Anything that forms part of the cooling airflow must stay clear.
| Location | Foam? | Reason |
|---|---|---|
| Solid rack side panels | Yes | Large flat area that reflects noise |
| Inside a solid front or rear door | Only if not part of airflow | Most racks draw air in at the front and exhaust at the back |
| Perforated doors and fan trays | No | Blocks cooling airflow and raises temperatures |
| Server room walls | Yes | Absorbs noise reflecting around the room |
| Server room ceiling | Yes, clear of vents | Reduces noise reflected down into the room |
| Over air conditioning grilles | No | Restricts the room cooling supply |
In a server cabinet, follow the manufacturer’s airflow direction, which is usually front to back. In the room, keep foam clear of cooling units, supply and return grilles, cable entry points and anything that needs to stay accessible.
Why Use Class 0 Foam for Server Rooms?
Class 0 foam is the right choice for server rooms because the foam sits close to power supplies, distribution units and dense cabling, where fire performance matters. GB’s Fireseal acoustic foam meets Class 0 under the UK Building Regulations and is self-extinguishing, and it does not melt or drip when exposed to a naked flame.
Our standard grey, red and blue acoustic foam does not carry a Class 0 rating, so we recommend Fireseal for server racks, comms rooms and equipment enclosures. See our Class 0 foam page for the full specification and our guide to fire retardant foam for UK fire rules.
| Property | Fireseal Class 0 Foam | Standard |
|---|---|---|
| UK Building Regulations | Class 0 | Paragraph A13(b) |
| Surface spread of flame | Class 1 | BS 476 Part 7 |
| Euroclass | B-s1,d0 | EN 13501-1 |
| Flammability | V-0 | UL94 |
| Hot surface performance at 100 degrees C for 96 hours | Pass | ASTM C411 |
| Air erosion resistance, 6 to 50mm | Pass | ASTM C1071 |
| Mould and fungus | Does not support growth | ASTM G21 |
Fireseal is an impregnated polyurethane foam with a density above 90 kg/m3 and a stated operating range of minus 30 to 100 degrees C. Its weighted absorption coefficient rises from 0.30 at 12mm to 0.45 at 25mm and 0.75 at 75mm, so thicker foam absorbs more where there is space.
Which Acoustic Foam Should You Choose for a Server Room?
For server rack panels and doors choose 1 inch (25mm) self-adhesive Fireseal, and for server room and comms cupboard walls choose 2 inch Fireseal sheets or self-adhesive Class 0 wedge tiles.
| Application | Recommended Foam | Why |
|---|---|---|
| Server rack side panels | Self-adhesive Fireseal 1 inch | Sticks to steel and fits behind panels |
| Solid rack doors | Self-adhesive Fireseal 1 inch | Absorbs noise facing the room |
| Wall mounted network cabinet | Self-adhesive Fireseal 1 inch | Lines small panels with little clearance |
| Comms cupboard walls | Self-adhesive Fireseal 2 inch | More absorption on larger surfaces |
| Server room walls and ceiling | Black self-adhesive Class 0 tiles (50mm) or Fireseal 2 inch sheets | Wedge tiles stick straight to walls and ceilings |
For server room walls and ceilings, our black self-adhesive Class 0 acoustic tiles are wedge profiled, 300mm x 300mm and 50mm thick, and come in packs of 24, 48 or 72. They are rated Class 0 to BS 476 Parts 6 and 7. For rack panels and doors, Fireseal sheets in plain and self-adhesive versions are listed on our acoustic foam page. For an unusual enclosure or a large room, speak to our team about thicknesses and quantities.
How to Fit Acoustic Foam in a Server Rack
To fit acoustic foam in a server rack, plan around the airflow, measure the solid panels, cut the foam to size, stick it to clean steel and then check temperatures.
Plan the work. Agree a maintenance window with whoever runs the equipment and follow your site’s electrical safety rules before removing any cabinet panels.
Map the airflow. Note the cabinet’s airflow direction, every perforated door, fan tray and vent, and mark the solid panel areas that can take foam.
Measure each panel. Measure the solid areas of each side panel and door, allowing 10mm clearance from vents, hinges, locks and fixings.
Check clearance. Measure the gap between each panel and the nearest equipment, cable or rail so the foam will not touch anything when the panel closes.
Cut the foam. Cut the foam to size with a sharp blade against a straight edge, as shown in our guide on how to cut foam.
Stick the foam on. Clean the steel so it is dry and dust free, peel the liner and press the self-adhesive foam firmly into place, working from one edge.
Check temperatures. Refit the panels, then compare inlet and exhaust temperatures from your monitoring system with the readings taken before fitting.
Mistakes to Avoid
- Covering perforated doors. Foam over a mesh door or fan tray cuts cooling airflow and raises equipment temperatures.
- Using non-rated foam. Standard acoustic foam does not carry a Class 0 rating, so use Fireseal near power supplies and cabling.
- Treating only the racks. Lined cabinets help, but bare walls and ceilings still reflect the noise that escapes.
- Expecting foam to block sound. Foam absorbs echo inside the room; stopping noise reaching other rooms needs mass and sealed gaps.
- Ignoring panel clearance. Thick foam can press on cables, rails or equipment when a panel or door closes.
Why Choose GB Foam Direct?
GB Foam Direct supplies high quality acoustic foam for server rooms, using foam sourced from trusted manufacturers. Foam quality matters in a server room, because low quality or degrading foam can shed dust and tiny particles over time, which can clog server intake fans or damage sensitive hardware. Our acoustic tiles are manufactured in the UK by our expert team at our High Wycombe factory, using precision CNC cutting.
We have converted foam in High Wycombe since 1976, with CNC cutting and experienced freehand cutters. We work to ISO 9001, give a 5 year guarantee against faults in manufacture and supply single sheets for one cabinet as well as larger quantities to installers and manufacturers. Orders placed before 11am Monday to Thursday are eligible for next working day delivery.
Speak to Our Team
If you need help choosing Class 0 acoustic foam for a server rack or server room, call us on 01494 441177, email sales@gbfoam.com or fill out our contact form. We are in the office from 9am to 5pm Monday to Thursday and 9am to 3pm on Friday.
Server Rack Acoustic Foam FAQs
Does acoustic foam work on a server rack?
Yes, acoustic foam on the solid panels and doors of a server rack absorbs fan whine and other high pitched noise that would otherwise reflect out into the room. It does not stop low frequency hum or vibration through the frame. For the best result, combine lined cabinets with acoustic treatment on the server room walls and ceiling.
Is acoustic foam safe to use in a server room?
Acoustic foam is suitable for a server room if it carries a recognised fire classification and is kept clear of the cooling airflow. GB Foam Direct’s Fireseal foam is Class 0 under BS 476 Parts 6 and 7, Euroclass B-s1,d0 under EN 13501-1 and rated UL94 V-0. Standard grey, red and blue acoustic foam does not carry a Class 0 rating.
What is Class 0 acoustic foam?
Class 0 acoustic foam is sound absorbing foam that meets the Class 0 standard of the UK Building Regulations, based on fire propagation and surface spread of flame tests under BS 476 Parts 6 and 7. GB Foam Direct’s Fireseal is an impregnated polyurethane foam that is self-extinguishing and does not melt or drip in a naked flame. It is sold in sheets of 200cm x 100cm.
What thickness of acoustic foam is best for a server rack?
1 inch (25mm) self-adhesive Fireseal is a practical thickness for most server rack panels and doors. GB’s product data gives Fireseal a weighted absorption coefficient of 0.45 at 25mm, compared with 0.30 at 12mm. Use 2 inch foam on comms room walls and larger enclosures where there is space.
Will acoustic foam make servers overheat?
Acoustic foam will not make servers overheat if it stays on solid panels and walls and never covers vents, perforated doors or fan trays. Foam is a thermal insulator as well as a sound absorber, so blocking the airflow path will raise temperatures. Compare temperatures from your monitoring system before and after fitting.
Can acoustic foam soundproof a server room?
No, acoustic foam reduces echo and reflected noise inside a server room but does not block sound passing through walls, doors or ceilings. Blocking sound needs mass and sealed gaps, such as heavier partitions and sealed doors. Foam is still worth fitting because it lowers the noise level that builds up inside the room.
Does GB Foam Direct sell self-adhesive Class 0 foam?
Yes, GB Foam Direct sells self-adhesive Fireseal Class 0 foam sheets of 200cm x 100cm in 1 inch and 2 inch thicknesses, and black self-adhesive Class 0 wedge tiles, 300mm x 300mm and 50mm thick, in packs of 24, 48 or 72. The adhesive bonds best to clean, dry, dust free surfaces such as painted steel cabinet panels. Call 01494 441177 for advice on larger server rooms.
Cameron has emerged as a key marketing expert since joining GB Foam Ltd in 2017. A graduate of the University of Winchester, with a professional background in Public Relations; he has combined his content writing and brand awareness expertise with an in-depth knowledge of foam products and foam conversion technology to enhance the company’s marketing strategies and industry presence. Cameron has led numerous marketing campaigns, in both B2B and B2C segments, to further brand recognition and open up new business avenues worldwide.