Use Less Water with Cool Machines Wall Spray Nozzles
In 1976, the cellulose wall spray method was developed. In Wyoming and Colorado by two different people. Did they know each other? Not sure. Ivan Sandau was among the first. He lived and worked in Estes Park, Colorado, and introduced the wall spray method to contractors. Winter hit and Ivan continued to spray homes. The cellulose was at nearly 100% moisture content. During the Spring thaw, the newly carpeted house had water seeping out of the perimeter walls, soaking the new carpet. The same thing happened with the Shumway brothers in Wyoming. They soaked the cellulose. Did Sandau and Shumway brothers know each other? Ivan does not remember.
The method persisted with long wait times (weeks) for the cellulose to dry. The high water content made the cellulose look like a cement rock in the cavities and held in place, with excellent results… but the amount of water continued to be a menace and by the 1980s-90s, the method lost popularity.
With decades of development and improvements in the wall spray industry, the moisture content has been drastically reduced. One can wall spray cellulose in the with 28% and much lower moisture content. The moisture level needs to be 25% or lower before it can be covered by drywall. Cellulose wall spray is growing strong and we train companies all over the United States. How then, do we use less water and still maintain an excellent density for wall spray materials?
Nozzle Design Has been Improved. Originally, nozzles had 4 or 6 spray tips. That resulted in way too much water. This was changed early on. Ivan changed to a two jet nozzle with a 25% spread. Today, tips usually begin with 25*** indicating this spread. Ivan, along with Dave Krendl continued to make improvements and developed a tear drop shaped nozzle that prewets the wall. Having the water prewet the wall right before the cellulose contacts it, helps it to stick. The nozzle also spreads the cellulose material in such a way to have the bulk of material come into contact with the water stream.
Equipment Setup Has Been Improved. Water pressure is now matched to the size of tips. The larger tips use lower water pressure (≈250psi). The smaller diameter spray patterns use higher pressure water (≈400psi). We find that it is important to have a set of each tips. As more and more cardboard is introduced into the cellulose production, you will need more water with lower pressure.
Recycling Has Been Improved. Manually returning the recycled material to a hopper takes a lot of work and requires a great amount of attention to adding and mixing the dry and recycled materials. Also, it takes a team that communicates well. Now, machines have dual hopper systems with two airlocks to allow the machine to meter the recycled with dry. This makes for a more consistent moisture content. Spraying with these machines, you can actually spray around 17%-19%. That is why the industry is now moving to the phrase “Dry Spray Cellulose.”
Technique Has Been Improved. The nozzles, pressures, tips and recycling are just a part of the complex nature of wall spray. When spraying, make sure you do not saturate the wall ahead of time. It is unnecessary. Especially, using the Cool Machine spray nozzle, this is happening when you spray. The nozzle is designed for you to hold at a 90 degree angle to the wall.
While this sounds complex, please note that when we are training new crews, within the first hour of training, most insulators are able to produce excellent results. If you would like training on-site or would like to discuss over facetime or whatsapp, we can help!