Most people have a very special relationship with the wooden deck that is in the rear portion of the dwelling that they are currently residing within because of the fact that this is the area where they conduct social events as well as put their feet up when they are weary at the end of the day. Hence, it stands to reason that maintaining your deck is going to be the only thing that matters to you, and suffice it to say that pressure washing it is a crucial aspect of its maintenance that you would do well to focus on.
To put it plainly, a deck that is not cleaned regularly by pressure washing companies spring is not going to last very long at all due to the reason that the dirt and grease layers will enter in between the floor boards and separate them when they freeze during the cold winter months. You should therefore pressure clean your deck at least once a year if not twice as much, and one thing to get squared away prior to you initiating this endeavor is what your ideal GPM would be in this situation.
GPM in this case stands for Gallons Per Minute, and your pressure washing apparatus should be putting out at least eight gallons during each minute in which it is operational. This gives you the chance to decrease or increase pressure as per your requirements without allowing the jets to get out of control. Another benefit to this rate of water output is that it reduces the likelihood of water wastage which can be quite problematic in areas that are low on water.