There are a number of different types of blankets for horses
. Here we would like to discuss blankets that are described as waterproof and breathable. This would suggest that the blanket have the ability to shed water during rain or snow and be able to breath. Breathability mean that as a horse sweats it's moisture would be released through the blanket.
Waterproofing Horse Blankets.
Waterproofing of material is measured by the amount of pressure it takes to force water through it. Generally heavy is not sufficient to cause waterproof blankets to leak although continual washing and pressure points that rub against the material may have a problem after time.
Breathable Horse Blankets
Breathable horse blankets
materials must have a way to to release sweat produced and trapped on the inside of the blanket to the outside atmosphere. This is accomplished in two ways. One method is that a waterproof membrane full of pores that are large enough for sweat to pass through and evaporate. There are claims that these pores are so large that rain will pass through. To stop this, the membrane is chemically treated so that rain water is repelled before it has a chance to penetrate through the material. The second method employs a monolithic membrane . This barrier will move moisture through a process of solid state diffusion. The sweat will collect on the surface of the membrane and pass through the material from areas of high concentration to the outside of the blanket. This is the method used by most blanket manufactures. What most people do not understand is that the primary factor for moving sweat from the horses body is the difference in humidity between the inside of the blanket and the outside environment. So the higher the relative humidity is between the inside of the blanket and the lower humidity on the outside , the greater the breathability. Thus horse blankets breath best in cold dry enviornments. Conversely they perform poorly when the temperatures rise and the humidity is high.
Waterproof breathable materials at best, will never be able be able to transfer all the moisture a horse can produce during rising temperatures in direct sunlight or if running in pastures. How you use the blanket is is often more important then the material itself. No mater how good the breathability of your horse blanket it will never approach releasing the amount of sweat a horse can produce in an hour.