
According to the State Preservation Board, out of session the two rooms are kept around ambient temperature, varying between 72 and 77 degrees. During the session, it's up to the management of each chamber. The House usually goes down to about 68 degrees, but fluctuates. The Senate is notoriously several degrees cooler.
And when we say several degrees cooler, the common term is "Ice box." Many Senate staffers regularly complain about the Arctic conditions and keep a thick jacket to hand.
So why keep it cooler in session? Simple: Floor regulations demand that men wear jackets and ties, and women wear business attire. Wool suits in a 77 degree chamber are no-one's idea of fun, and you can't take a drink on the floor, so the thermostat comes down. After that, it's down to the whim of the individual chamber chiefs.
It's not an exact science, and there are structural differences between the two rooms. One, the Senate is actually smaller than the House by a good few yards, making it easier to control the temperature. Two, during the session that House is usually working for more hours per day, meaning those big lights are blazing longer and pumping out heat.
But the Senate management likes it icy, even though that makes it uncomfortable for staff whose seats are positioned right over the brass floor vents. Seems it's saved some wear and tear on the paint, though.
Legislature, Texas House of Representatives, Texas Senate, Renovations, Temperature, Texas State Preservation Board