Attic temperature

I will be growing in my attic using a 1000 w HPS lamp. Controlling temperature is critical since I live in a hot region. What do you suggest?

There are several ways of controlling the temperature in your grow space in the attic. Probably the most common method is to enclose the growing area. Then only the grow space, not the whole attic, needs cooling. The enclosure could be as simple as a wooden frame with stretched polyethylene walls. A more permanent space can be built with sheetrock. The space should be about 8 feet high, with a roof that slopes slightly to one side.

Excess heat in the attic can heat the space. To cool the attic, an exhaust fan is installed on the roof or at the top of a wall.

An air-cooled reflector should house the 1000 watt lamp. The reflector unit has input and output air hoses that push air from outside into the reflector, which encloses the air using a glass plate. The hose draws air from outside the chamber and delivers it to the attic exhaust fan. The light’s extraneous heat never enters the growing chamber.

An exhaust fan is installed in the highest part of the space’s ceiling so that the hottest air can be exhausted. An air intake fan is installed near the floor to bring in cool air. During cool periods this will be your main source of cooling the space.

During warm periods the heat is controlled using an air conditioner. There are two convenient possibilities. The first is a room air conditioner such as the ones placed in windows. The air conditioner can be supported by a wooden frame or tall furniture. It should be placed near the top of the wall so that the cool air floats down to the plant area. Circulating fans help disperse it in the space. Another possibility is a portable room air conditioner. This unit is moveable and usually comes with wheels. The heat it gathers is exhausted through a tube which can be released near the attic exhaust fan.

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