Many times a ghillie suit’s quality is based upon the amount of camouflage material it has. We know that they tend to trap heat. The temperature inside of the it can reach over 120 degrees F even when ambient temperatures are much lower. The problem is that the more material they have, the hotter and heavier they becomes. To combat this, the operator must stay hydrated to remain cool.
Remaining cool in hot weather is one of the most difficult tasks for human beings. We can only cool down by sweating and by air evaporating the sweat from our skin. To address the first issue, we must be able to carry ample water with us while wearing our suit.
One of the best devices one can incorporate into their ghillie suit is a water bladder. A Camelbak type water bladder can be easily concealed within a ghillie suit. You can conceal one inside your suit by sewing a small pouch made of BDU material or tough cordura on the inside of the upper back of the suit. Use a velcro closure at the top and allow room for the water tube.
While wearing a ghillie suit you are almost never laying on your back so you do not have to worry about putting your weight on the bladder. For a better drinking position, you can extend the water tube and run it to your wrist and attach it to the inside of the sleeve. This will make it easier for you to find your drink with minimal movement.
The next method is evaporated cooling. We must have airflow over our body to remove the heat and evaporate the sweat produced. A easy method of remaining cool is to incorporate air vents into your ghillie suit. While many are already made with very thin mesh to facilitate airflow, wide open vents allow for quick cooling. Properly placed vents will allow the airflow to provide a natural cooling effect. Custom made ones are often created with air vents and water bladder attachments for maximum comfort.