(325) 208-3607 Book a site survey
  1. Home
  2. Warehouse heat

Why the roof is warm and the floor is cold.

In a tall building, heated air rises and stays at the top. The heaters keep running, the roof deck gets the heat, and the people and product on the floor get what's left. It's called stratification, and it's a common reason a warehouse feels cold in winter.

The same building, twice

Without fans, and with them.

The colour bands show where the warm air sits — orange under the roof, blue at the floor. The dashed arrows show which way air moves.

Warehouse without destratification fans A warehouse cross-section with a heater high on each wall. Arrows carry the heated air up to the roof. The colour bands run from orange under the roof to blue at the floor, where the racks are. Warmest air Heat rises past the racks Cold floor Heater Heater Without fans
StratifiedHeaters run, the warm air climbs to the roof deck, and the floor stays cold. Heat is lost through the roof, and the heaters run longer to keep up.
Warehouse with a destratification fan The same cross-section with a large ceiling fan under the roof. Arrows carry air down from the fan to the floor between the racks and back up the walls. The colour bands are nearly one colour from roof to floor. Fan Even, roof to floor With a destratification fan
MixedA large, slow ceiling fan pushes the warm air back down to the floor. Temperatures even out, the floor warms up, and the heaters have less to do.

Illustrative drawings, not measurements. How much difference fans make depends on the building's height, insulation, heaters and doors — we look before we recommend.

What we look at

Heat where the people are.

Heaters
Gas unit heaters and radiant tube heaters — serviced, repositioned or replaced, flues checked.
Destratification fans
Large slow ceiling fans that push warm air back down in winter and move air in summer.
Dock doors
Open dock doors let heat straight out. Air curtains and door heaters where they make sense.
Controls
Thermostats at working height, not up on a column next to the heater.
Ventilation
Exhaust fans and make-up air for forklifts, welding and process fumes.
Radiant tube heaters running along the ceiling of a tall warehouse above rows of pallet racking
A large, slow ceiling fan hanging from the high roof of an empty gymnasium with a polished wooden floor
Summer, too

The same fans move air in July.

Run in the other direction or at higher speed, large fans make a hot warehouse, gym or shop feel cooler by moving air across people — without cooling the whole volume of the building.

Businesses

Big rooms

Warehouses, shops, gyms, churches and auditoriums.

Homes

Vaulted ceilings

The same thing happens at home. In winter, run ceiling fans slowly in reverse to bring warm air down.

Cold floor, warm roof?

Book a site survey.

We'll look at the heaters, the doors and the height, and tell you what would help.

Book a site survey (325) 208-3607
Call Survey