How Do Fabric Ducts Achieve Even Indoor Temperatures?

Insights

A room can have enough heating or cooling capacity and still feel uncomfortable. One person may be sitting beneath a cold draught while somebody a few metres away feels too warm. In warehouses and factories, the difference between floor and ceiling temperatures can be even greater.

The problem often comes down to how conditioned air is distributed. Fabric ducting allows air to leave through many carefully positioned openings along the length of the duct, helping designers spread heating or cooling across the areas that actually need it.

Why Do Hot and Cold Spots Develop Indoors?

Traditional ventilation systems may supply large amounts of air through a relatively small number of grilles or diffusers. This can create areas where air movement is concentrated, while parts of the room receive much less.

Warm air also naturally rises. In buildings with high ceilings, this can produce a layer of warm air above the occupied area while people closer to floor level remain cooler.

Cooling presents the opposite challenge. Cold air is heavier, so poorly controlled supply air can fall rapidly beneath an outlet and create an uncomfortable cold spot.

A well-designed ventilation system therefore needs to consider the direction and speed of the air as well as its temperature.

How Do Fabric Ducts Spread Air Around a Room?

Fabric ducts can release air continuously along much of their length.

Instead of relying on a few separate outlets, designers can use laser-cut perforations, micro-perforations or fabric nozzles to send different quantities of air towards specific areas.

Prihoda’s Decathlon Glasgow installation, for example, used rows of fabric nozzles to distribute air across a large retail space with high ceilings. The system was designed to avoid stagnant areas, hot spots and uncomfortable draughts.

This type of distributed delivery helps reduce the temperature differences that can develop when most of the heating or cooling enters the room from one location.

How Do Micro-Perforations Help Maintain an Even Temperature?

Micro-perforations are very small openings positioned around the fabric duct.

They allow a relatively large volume of air to enter the room gently through thousands of individual points. The supply air then mixes with the surrounding room air rather than travelling as one concentrated jet.

At FBD Insurance, Prihoda used micro-perforation diffusers across open-plan office floors. The finished system produced an even temperature gradient while avoiding noticeable air movement over the desks.

This approach can work particularly well in offices, classrooms and other spaces where people remain seated for long periods.

How Can Fabric Ducting Deal With Warm Air at High Level?

Heating tall spaces presents a different problem because warm air naturally wants to remain near the ceiling.

Fabric ducts can use larger perforations or nozzles to give the supply air enough momentum to reach lower parts of the building.

At Aerospace Bristol, for example, fabric nozzles were used to help warm air travel down from high level into the occupied zone. The same installation used gentler perforated airflow in lower-ceiling areas where that amount of throw was unnecessary.

The outlet design can therefore change according to ceiling height and how far the air needs to travel.

Can Different Parts of the Same Room Receive Different Airflows?

Yes. This is particularly useful in industrial buildings where different areas have different heat loads.

A production machine may generate considerable heat while nearby staff are seated at workstations. Supplying exactly the same airflow everywhere may leave one area uncomfortable.

In Prihoda’s Tarpey Harris installation, different perforation patterns were used along the same ducts to provide different air volumes and velocities to machinery and seated employees. The resulting system produced a more even temperature pattern across the factory.

This illustrates why understanding how each part of the room is used is important during the design stage.

Why Does Duct Position Matter?

Even the correct airflow pattern can struggle if the duct is installed in the wrong place.

Designers need to consider ceiling height, room shape, machinery, shelving and where people normally spend their time. Heating and cooling modes may also require different air behaviour.

Prihoda’s fabric duct systems are therefore designed around calculated airflow patterns rather than using the same hole arrangement for every installation. At Whitmore High School, for example, airflow and velocity were mapped before installation so the perforation arrangement could be matched to the room.

Good temperature control starts with understanding where the conditioned air actually needs to go.

Do Fabric Ducts Guarantee an Even Temperature?

No ventilation system can guarantee identical temperatures in every part of a building.

External sunlight, open doors, machinery, occupancy and building insulation can all affect local conditions.

Fabric ducting gives designers greater control over how supply air is distributed, which can help reduce avoidable temperature differences. The best results come when the air volume, outlet pattern, duct position and heating or cooling load are considered together.

 

FAQs

Why Is One Part of My Building Warmer Than Another?

Uneven temperatures can result from poor air distribution, high ceilings, sunlight, machinery, open doors or different levels of occupancy across the building.

Can Fabric Ducts Be Used for Both Heating and Cooling?

Yes. Different perforation and nozzle arrangements can be used depending on whether warm or cool air is being supplied and how far it needs to travel.

How Do Fabric Ducts Prevent Cold Spots?

They can spread cool air through many outlets rather than concentrating it through a small number of grilles, helping the air mix with the surrounding room before reaching occupants.

Are Fabric Ducts Suitable for High-Ceiling Buildings?

Yes. Fabric nozzles can provide greater air throw where conditioned air needs to travel from high level into the occupied area.

Does Every Fabric Duct Use the Same Perforation Pattern?

No. Hole size, position and quantity can be designed around the airflow requirements, room layout and areas that need heating or cooling.