You’ve landed a roof that justifies purchasing an airless sprayer. “Which one, why and what all is involved” are the next questions to go through your head.
What to Consider when Purchasing a New Pump:
Consider the size of your roof project, as well as the average size that future roof projects may be. Is the average roof that you think you will be doing in the 10 to 12,000 square-foot range or larger?
Sizing your pump is an easy way to save money up front and still get the job done. There is actually no need for a pump the size of an 833 if your average roof is 5 to 10,000 ft.²
Roofs that size can be done with a 7900 all day long. If you get an occasional large roof a 7900 will still perform well, it will just take a little longer when you start top coating.
If your average job is going to be 10,000 square-foot & up, then you’re better off to start with something like a Graco 833. Another question to ask is, are you going to be doing acrylics or silicone. If silicone is in your future and spraying is the method you want to do, then a Graco 933 is your number one option. The 933 will allow you to spray silicone and if you desire to, you can use a second set of hoses and gun to spray acrylics, although it’s not recommended due to labor required to insure pump is spotless of each chemistry before using the other chemistry. Most contractors who spray both acrylics and silicone have dedicated pumps for each system.
Hose Configuration is Equally Important
Once you have decided what size pump you’re going to need, you’ll then need to look at your hose configuration. Make sure that the dealer you’re purchasing from is not trying to make a sale by selling you the wrong size and length hoses just to get the price down. To maximize efficiency and performance you’ll want to run as much of the largest size hose recommended for your pump as you can. For instance on roofs, most contractors run 150 to 200 feet of half-inch hose with a 50 foot section of 3/8 hose connected to their gun or a Roof Rabbit.
Silicon contractors on the other hand, if going over 150 feet of total hose, will typically start out with 1 inch hose for 100 to 150 feet before necking down to 3/4 and half inch, not to exceed half inch or smaller house. This is simply due to the physical characteristics of silicon and it not liking to be sprayed.
Doing these things, as well as using hose reels will set you up for success when you’re ready to tackle the roof that you’ve landed.
Chad Hedrick, Roof Coating Life