The only way to vacuum 100% dust-free is to do so with a central vacuum system that vents to the outside of your home. Now that you have the first part down (the central vacuum system), read below to learn how to get all that dust outside where it is safer for your lungs and allergies.
Step 1 - Select a Location
The location you select for your exterior exhaust needs to be away from walkways, lounging areas, and entryways. It is best to select an area that isn't plainly visible as the exhaust can be unsightly.
Step 2 - X Marks the Spot
Head inside and drill a hole from the inside all the way through to your exterior in the place you want the exhaust. Use a compass or trace something to make a circle around the hole you have just drilled. Make sure to use the hole as the center of your circle.
Step 3 - Cut Out the Circle
Use either a hole saw or hammer drill to cut out the circle that you just drew. Remove and discard the drywall.
Step 4 - Head Outside and Do It Again
Go outside and use the hole you drilled as the center for your circle again. After your circle has been drawn, cut it out.
Step 5 - Run the Tubing and Attach the Flap
Run the tubing from the inside to the exterior. Push an extra 1 to 2 inches through to leave protruding through on the outside. Attach a trim ring to the interior. Head outside and attach a trim ring to the exterior.
Now you can either attach an exhaust flap or a 45-degree coupling. If you choose to go with the coupling, be sure to point it downward. An exhaust flap is merely screwed into place.
Step 6 - Seal the Joints
Using the PVC cement, seal the joints on both the interior and exterior to keep the tubing securely in place.
Step 7 - Hook Up Your Central Vacuum
Connect your central vacuum system to the exhaust tubing. You can now enjoy the only way to vacuum 100% dust-free and enjoy clean air free of pollen, dust mites, mold, and other allergens.