Dense Packing with a Cool Machine: No guess work!

airlock-pressure-gauge copyIt is all in the gauge! Cool Machines come with an airlock gauge which tells you exactly how much pressure you are using to dense pack material into a wall system. We eliminate the guess work. Here is how to dense pack accurately.

How to set a Cool Machine’s PSI

Every Cool Machine has an airlock with a pressure gauge. A green indicator marks the acceptable dense pack ranges (3.5 to 4.0 PSI).

All you need to do is attach the amount of hose you need[1. 1-If you add or remove a section of hose during the same job, recalibrate the pressure. Additional hose will cause a drop in PSI. Less hose will cause an increase in PSI.] for your particular job. Place the end of your hand over the end of the hose to cuff the air. Turn the blower on and using the variable control blower dial turn it up or down to gain the right pressure.

That is all! No special tools, measuring devices are needed. You get the exact pressure every time!

Choosing the Right Material for Dense Pack

Whether you use cellulose, fiberglass or rockwool, there are no special materials for dense packing. Companies tout particular material for various applications, however, standard insulating materials are sufficient. With dense packing, your concern is packing the material in at the correct PSI. When doing so, it does not matter whether you use a stabilized product or not. Do not concern yourself with paying for expensive products that include starch. Those materials create more dust and do not perform unless they are activated by water. Additionally, they are more expensive.

Some companies require certification training so you can use their product for dense packing. I do not make it a practice to speak negatively about any particular brand of insulation or machine. Therefore, I will not name them here. Just be aware that dense packing does not require any special certification. Maybe to use someone’s particular product, you need to pay for their training, however there are plenty of products available to all contractors whether you have training or not.

We have seen particular contractors require a brand-name system. Unless you can convince the contractor otherwise, you will have to meet their demands to win their project. Also, you may need certifications to perform certain government-sponsored jobs. However, generally-speaking, you do not need specialized certification.

Dense Packing in New Construction

Whether you use cellulose or fiberglass, the method is the same. You need to create a temporary “wall” to hold the insulating material in place and to resist bulging.

When using cellulose, you will definitely want to use a fabric material (i.e., Insulweb or IC Pro Pack). These fabrics are very sturdy and will prevent bulging when the appropriate PSI is used when dense packing. You will need to affix the fabric to the wall, using a pneumatic stapler, stapling the material every inch on the wall studs. After stapling, cut a slit in the fabric and attach a section of PVC pipe to the end of your hose (about 4’ is a good length). Stick the pipe into the wall and fill the upper part then the lower.

When using fiberglass, since the material does not produce the same amount of visual dust [2. 2-It is still very dusty and a mask is necessary. You just don’t have the cloudy cellulose impairing your vision], you can use the more inexpensive netting (i.e., 1/6 inch mesh). Again, the process is the same as cellulose above.

Rockwool is used to create a dense, sound deadening barrier. This is very commonly used to isolate home theater and sound studio walls. Often it is easier to find and install panels of rockwool, yet you can dense pack this as well with excellent results.

Dense Packing in Existing Construction

You will want to use a smaller diameter hose. I recommend a 1-1/2 inch hose that is 8 feet long. The larger diameter will minimize hose plugging and allow more material to flow making the job faster. Make sure that when you are reducing from 3 inches to 1-1/2 inches that you allow about 4 feet of reducing steps. Going from 3 inches to 1-1/2 inches in one step will make your job more prone to plugging the hose.

Drill a 2 1/2” or 3” hole into every insulatable[3. 3-Be very careful to walk through the inside of the house to avoid cold-air return cavities and spaces where walls are not sturdy–behind cabinets, thin plywood walls]. cavity. Drill the hole close to the bottom sill plate. With existing walls, the process is a bit more difficult. You are blind to the material as it flows into the cavity. You are able to feel and see the insulation pack in the clear vinyl hose as it fills the cavity. Insert the vinyl hose, into the cavity and “snake” it up the wall. Cutting a 45 degree angle on the hose will allow it to go more smoothly into the wall system.