What Is Sandblasting and Why Would You Do It?
Call in the pros to blast away paint, smooth surfaces, and clean concrete
Highlights
Sandblasting is a technique that forcefully applies abrasive particles to clean, strip, and prep surfaces.
Do not attempt sandblasting yourself, as it can be dangerous and may damage your property.
Professionals rarely use silica sand now because of its health and environmental risks; instead, they rely on other materials like aluminum oxide, glass beads, and walnut shells.
Scraping peeling paint off your home’s siding is a time-consuming, tedious task. If you call a contractor to do the job, they might suggest sandblasting. But what is sandblasting, and why is this powerful surface cleaning and texturing technique not one you typically want to DIY?
What Is Sandblasting?
Sandblasting is a technique that forcefully applies a stream of abrasive particles onto hard surfaces under high pressure. When the process was first invented, the particles were always sand. While you’ll still commonly hear professionals refer to the process as sandblasting, these days, the correct technical term is abrasive blasting. That’s because a wide range of safer and often more effective abrasive materials are now used in place of sand.
What Is Sandblasting Used For?
Sandblasting can clean, smooth, roughen, or otherwise modify the characteristics of hard surfaces. Professionals use the technique for a wide range of purposes, including:
Cleaning or prepping metal or masonry surfaces
Removing peeling paint from house exteriors
Removing mold
Creating decorative patterns on walls or glass
Smoothing scratched surfaces
Sandblasting Pros and Cons
Sandblasting is a fast, efficient way to clean or strip your surfaces. The wide variety of abrasives means you can use the technique on many materials. However, sandblasting can be noisy and messy, requires pricey machinery, and is not a recommended DIY technique—get it wrong, and sandblasting can harm your health or damage your property.
Sandblasting Materials
Originally, silica sand was the go-to abrasive material. However, this substance generates a ton of harmful dust particles that can be a significant health hazard. In some regions, there are bans on the use of silica sand for abrasive blasting; in others, it’s possible to use it in certain circumstances, but only when applied by a professional with an appropriate permit. Fortunately, there is now a wide range of alternative, safer materials. The one you select will depend on the project type and sandblasting method, the effect you are looking for, and your budget.
Some common abrasive blasting materials include:
Aluminum oxide: Reusable, produces minimal dust, and is ideal for cleaning or paint removal.
Corn cobs, walnut shells, baking soda: Soft and sustainable materials for cleaning delicate surfaces like wood, softer stone, or glass.
Glass beads: Can polish up and brighten harder surfaces without creating a lot of dust.
Plastic grit: Versatile and tough, often used on fiberglass surfaces.
Steel grit: Tough enough for cleaning and rust or paint removal on metal siding.
Silicone carbide: An extra tough material, professionals commonly use this when polishing hard stone surfaces.
Sandblasting Methods
In addition to the many materials to choose from, there are various methods to apply the abrasive particles. Some examples include:
Dry blasting: The traditional technique of applying particles via high air pressure.
Wet blasting: Modern, common, and effective, this method involves blasting a wet slurry onto surfaces. It provides a more targeted stream, there won’t be any messy or risky airborne particles, and it prevents overheating.
Centrifugal blasting: Uses a blade wheel to mechanically propel the particles at the surface, rather than relying on riskier compressed air.
Vacuum blasting: Another technique that minimizes dust particles. It does this by vacuuming them back into the blasting machine as they become airborne.
Dry-ice blasting: This modern and innovative technique uses carbon dioxide pellets that dissolve with the heat of the process on hitting the surface. It’s non-abrasive and non-toxic but requires a specialist kit and excellent ventilation to prevent carbon dioxide poisoning.
DIY vs. Hiring a Pro
While professional sandblasting costs an average of $3,200 and the average cost to rent a sandblaster is $200, this is not a project to attempt to DIY and save money. If you get the tricky-to-master technique wrong, you can damage the surface, and there are major environmental and health respiratory risks. Airborne abrasive dust particles can damage your lungs, skin, and eyes.
Hiring a professional sandblasting company near you means they will select the best materials and sandblasting techniques for the job and surface. They’ll also have the right equipment, protective gear, and knowledge of state rules or permit requirements for abrasive blasting.
If you want to clean siding or another surface via DIY, consider sandblasting alternatives such as pressure washing your house.
Frequently Asked Questions
When professionals sandblast surfaces, they apply fine, abrasive particles using high-pressure equipment. Depending on the surface, equipment, and particle type, this technique will remove dirt, smooth imperfections, or create a textured finish. When you sandblast, microscopic particles can become airborne, so the right materials, specialist protective gear, appropriate ventilation, and other precautions are often needed to protect people and the environment.
Sandblasting metal is common. Professionals often use this technique to remove paint, rust, scratches, or ingrained grime. They will choose different abrasive materials to sandblast, depending on the type of metal, its density, and whether cleaning or stripping is required. For example, it’s possible to sandblast aluminum siding. But because this is a softer metal, it’s important not to select a material that is too abrasive—steel grit isn’t likely to be a good choice.
Both sandblasting and sanding can gradually wear down the surface when applying the technique. However, sandblasting is a much faster and more aggressive method. It allows you to cover large areas more quickly, smoothly, and effectively, but it can damage delicate surfaces, and unlike sanding, it isn’t a suitable DIY task.