HVAC for High Bay Buildings

[mindsurfer]

Hello everyone,

I have to design an industrial building that has ceilings at 50 ft high and 70k ft^2. For cooling I will be providing evaporative coolers with 100% outside air. The air will be exhausted with roof fans. For winter (freeze protection I am thinking either direct fire heaters on the evap coolers or unit direct fired unit heaters inside the building. Can anyone help me with the following.
1. since the ceiling lights are so high up and there will be roof exhaust fans do I include the lighting loads on the load calc?
2. If the answer to the light question is that the heat loads from the lights will rise and be exhausted by the roof fans, than do I use this same logic for the overhead crane motor loads and also do I just consider the first 10 ft of wall height for heat transfer and assume that the rest heat load will rise up and taken out of the space by the roof fans?
3. Does any one know how much heat load a welder machine and plasma cutters provide to the space (or how I can estimate it)?

Thanks.

 

[nuuvox000]

1. I would include them.
2. Do you have huge exhaust fans? It might take them a long time to exhaust the entire space. I would include the loads myself.
3. Look at the full load amps rating or kilowatt rating of the machines. Whatever power they're using will be turned into heat. Machines are just space heaters with extra steps.