When drastically changing paint colors, most people would remove the old paint from the surface first and then repaint it. However, different surfaces require different methods of removal. This is why it is important to choose the best paint stripper for specific surfaces, like wood, concrete, masonry, and brick.
Choosing the right type of paint stripper ensures that paint is removed easily and will not damage the surface or material it is painted on. Paint strippers make use of strong chemicals that may work great with specific surfaces but are ineffective on others.
Even if you still have some leftover paint stripper that you used to effectively remove acrylic paint that was accidentally spilled all over your furniture, you may not get the same results when using it on your deck. That is why you need to know which one to use for the specific surface you will be working on.
If this already sounds tedious to you, don’t worry because we are here to help you out. We will guide you on picking the right kind of paint remover for your needs.
Choosing the Best Paint Stripper
When it comes to choosing the best paint stripper, people immediately think that using liquid removers is the only way to do so. They also believe these removers are all just the same, that is why many make the mistake of just grabbing the first can of paint remover they see on the shelf and hope that it will do the job.
While they may hit the jackpot and get the right one that works effectively without affecting the surface it is painted on, there is also an equal chance that it will not easily remove the paint, or even cause damage to whatever surface paint is applied on.
But before you make the same mistake as others did, you need to familiarize yourself with the different ways of removing paint to help you choose which one is most appropriate for your needs. Paint removal in any surface is generally done in two ways: through chemical paint strippers in liquid form and via non-chemical means.
Liquid paint strippers are categorized into three: biochemical, caustic, and solvent strippers.
Biochemical Paint Strippers
The most environment-friendly of the three, biochemical paint strippers use solvents that are plant-based. It may consist of lactic acid taken from corn sugar, terpenes from citrus rinds or pine trees, citric acid, dimethylsulfoxide from wood pulp, and an organic compound called NMP or N-methyl-2-pyrrolidone, among others.
Because it uses mostly natural ingredients, this type of paint remover hardly emits any odors. Unfortunately, this compromises its ability to remove paint, as it lacks the chemicals that can easily and swiftly do so. That is why when using biochemical strippers, it will take time before the entire paint is removed. Despite this, it can be used on any surface without causing damage but multiple applications may be needed.
While considered safer than caustic and solvent paint removers, the NMP present in biochemical paint removers is known to be risky for women and those who are exposed to it for long periods and can cause reproductive issues, that is why should still be used with caution.
Caustic Paint Strippers
The caustic paint stripper, on the other hand, is water-based and uses lye as its main ingredient. The lye used in this type of paint stripper can either be caustic potash, also known as potassium hydroxide, or caustic soda, or better known as sodium hydroxide.
It has a high pH-level, typically ranging from 13 to 14, and it removes paint by breaking down the chemicals present. This is done by applying a thick layer of it, ranging from 1/8 to 1/4 inch, over the paint and allowing around 30 minutes of dwell time. However, this type of paint stripper is ineffective in a -10 degrees Celsius environment.
The lye present will react to the dried paint to turn it into soap, allowing the paint to be lifted or loosened from the surface it was applied to. But due to its alkalinity, neutralizing the surface after paint removal is important, and this is done by applying a solution of water and vinegar afterwards.
This type of paint stripper is considered the best latex paint remover and can also remove oil-based and enamel paints well on certain surfaces. However, it does not really work with acrylic paint, polyurethane, and epoxy. Also, it has the tendency to corrode aluminum and cause hardwood to blacken. Not only that, it is also known for attracting moisture, which can damage wood.
While water-based, it must still be handled carefully because it is known to cause irritation to the lungs and eyes, or even skin burns.
Solvent Paint Strippers
Known for having the most VOCs, or volatile organic compounds present, solvent paint strippers consist of chemicals that allows paint and coating, including epoxy, polyurethane, acrylic, polyaspartic, and polyuria, to swell up or bubble. This happens because the bond that adheres paint to the surface is softened up or dissolved by these chemicals, allowing for its easy removal. While neutralizing is unnecessary, the surface needs to be washed with either mineral spirits or water after removing the paint.
Methylene Chloride used to be the primary component of solvent paint removers, but its known health risks make it dangerous for use; in fact, this compound has now been banned for consumer use. That is why other compounds, such as toluene, ketone, and acetone are being used for it.
Because of the higher amount of chemicals and VOCs present, solvent paint removers pose more health risks and are known to emit the strongest fumes. On the upside, these chemicals also make them quite corrosive and great for heavy-duty use. And unlike caustic paint strippers, they can be used even in a cold environment without issue.
Aside from chemical means, paint can also be removed by using heat or via sanding or power washing.
Using heat to remove paint should be done with caution, especially if a torch or a heat gun is used. A torch has an open flame to remove paint, which can be a fire hazard, and despite being flameless, a heat gun can also cause fires and create toxic fumes. That is why a low-intensity infrared heater is ideal for this method, but it also has its own limitations in terms of which surfaces it can be used on. But regardless of what tool is used, the heat causes paint to soften up, allowing it to be scraped off easily.
Either done using a machine or through hand, sanding will remove paint through friction. This method can be considered intrusive, as it may also strip away layers of the surface where paint is applied to.
Not everyone knows that power washing is not just for cleaning; it can also be used to remove paint, especially on exterior surfaces. However, this method can be challenging, as mishandling a power washer or using the wrong amount of pressure can cause damage to any surface.
Before removing paint and regardless of which method will be used, it is vital to determine if the paint is lead-based, especially if the house dates back to 1978 or earlier. Paint stripping will disturb lead and create dust and chips that can be easily inhaled, ingested, or absorbed and may cause lead poisoning that can lead to death.
Lead paint test kits can be used to know immediately whether it is safe to strip off the paint on a particular surface or not. And for large scale paint removal on such homes, buying in bulk is practical because a basic kit will not be enough to test all suspected areas; they can only be used in a single room on average.
Water-Based Paint Remover vs. Oil-Based Paint Remover
When it comes to paint, water-based and oil-based ones are quite different from each other, from application to removal, so it is important to understand the differences between a water-based paint remover vs. an oil-based paint remover.
Water-based paint, which is generally either latex or acrylic, is known to be easier to remove than oil-based paint, and it can even be done manually without using chemicals. In fact, water-based paint that is not yet completely dry can even be removed by just soap, water, and some elbow grease.
Sanding and heat can also remove water-based paint quickly. But if using paint removers, caustic strippers work best for latex paints, while solvent strippers are suitable for acrylic paints. While both water-based, acrylics are resistant to the chemicals found in caustic strippers, unlike latex ones.
On the other hand, oil-based paint is tougher to remove, that is why the stronger solvent paint strippers and heat are used for their removal. More effort is needed when dealing with oil-based paint compared to water-based ones, that is why its compatible removers are harsher.
While biochemical paint strippers can be used for both oil and water-based paint, it will require more time to do so; despite its versatility, it is the least aggressive type of paint remover. Because of this, the dwelling time can take several hours to an entire day before it can fully penetrate the paint and allow easy removal. Also, it will take several coats before the paint can be entirely removed.
Zero VOC Paint Stripper
For those who prefer a safer method of removing paint through liquid means but would rather avoid the lengthy process involving biochemical strippers, a zero VOC paint stripper is ideal.
The VOCs present in both paint and paint strippers are what makes them dangerous to use, especially to pregnant women. This is because VOCs are capable of evaporating, and when they interact with the gases present in the atmosphere, they can create the harmful ozone gas.
The strong fumes emitted when opening a can of paint or paint stripper is indicative of the level of VOCs present. Simply put, the stronger the smell, the more VOCs present. Unfortunately, the smell is not the only aspect everyone should watch out for. There are actually so many health hazards attributed to VOCS, such as:
- Kidney damage
- Liver problems
- Damage to the central nervous system, especially the brain
- Irritation to the eyes, nose, and throat
- Recurring headaches
- Chronic fatigue
That is why it is vital to limit the exposure to any substance that contains them, including paint strippers. Solvent strippers are known to have the most amount of VOCs present among the three, typically followed by caustic ones. While biochemical strippers use natural ingredients, these ingredients may still contain certain amounts of VOCs, and it is hard to determine the actual present.
Zero VOC strippers, on the other hand, are generally considered as the safest due to the minimal amount of VOCs present. Because of this, the health risks are as good as eliminated. Not only that, those who use it no longer have to deal with fumes, because zero VOC paint strippers will hardly emit any odors. And due to the lack of these toxic compounds, they are also an eco-friendly option.
Best Paint Stripper for Wood
While there are plenty of paint strippers that can work on various surfaces, it is often better to choose specialized removers that work on specific surfaces only, especially if the paint removal only involves one type of surface. And when it comes to choosing the best paint stripper for wood, there are a couple of options to choose from.
Liquid Paint Strippers
Liquid paint strippers can be used for all kinds of wood surfaces, making them generally the best option, including for spot removal of paint on wood surfaces. While caustic, biochemical, and solvent strippers will all work on wood, it is still important to choose the right type based on the kind of paint to be removed, as well as what kind of repainting will be done afterwards.
For wood that has thick layers of paint and will be repainted a different color, caustic strippers will work best, even on a carved surface because it can cause discoloration or permanent stains. But if the aim is to preserve the look and feel of wood as much as possible, solvent strippers are ideal because they are less intrusive with wood.
Good old fashioned sanding is another method of removing paint on wood, often with the use of an electric or power sander. However, this should ideally be used only on flat surfaces, as it can ruin woodwork, such as moldings, trims, and decorative wood. That is why this method is recommended only on wood floors and walls.
If working with wooden furniture, including cabinets, moldings and baseboards, decorative or carved wood, and other similar wood surfaces, sanding is possible but only when done by hand using a sanding block and with the right kind of sandpaper. However, this can be time consuming because a single pass will not be enough to entirely remove paint; the wooden surface must be sanded by both fine grain and coarse sandpaper to get the best results.
Another method of removing paint on both even and uneven surfaces is through heat. Again, it should be done with caution, as too much heat can damage the wood itself and not just remove paint.
To avoid this, it is better to use a low heat infrared heat stripper than a torch with an open flame or a heat gun that produces high heat. However, the bulky size of an infrared stripper makes them not ideal for use over furniture, that is why they are best used on large, flat wood surfaces.
Paint removal on outdoor surfaces, like decks and siding, using heat can also be done using steam strippers. Best for heavy-duty use, the steam produced acts as an emulsifier that will allow paint to be easily removed. While the risk of fire is minimal since the steam’s temperature never exceeds 212 degrees Fahrenheit, this method is known to cause warping on the wood, which can be difficult to fix.
For decks and outdoor wood surfaces, power washing may be used to remove paint, not just to clean surfaces. However, peeling paint must be removed first and paint stripper should be applied on the surface and allowed to dwell before doing so.
The right water pressure is needed because weak pressure will be ineffective in removing paint, while water pressure that is too strong can damage the wood. Removing latex paint will require less water pressure, since it is easier to remove than oil-based paint.
When done right, this can be the fastest way to remove paint, especially in a large area. Pressure washing can only be done outdoors, as it will involve large volumes of water that can cause all sorts of issues when used indoors.
Do note that regardless of which method is used, it will still involve scraping the paint off. If you are expecting paint to fall off on its own, that will never happen. While most of these require scraping as a final step, power washing normally involves scraping before using the pressure washer and afterwards for any stubborn paint remaining.
Best Paint Stripper for Concrete
Concrete is known to be porous, which means it will easily absorb paint, but this characteristic also makes its removal much harder. That is why finding the best paint stripper for concrete can be quite the challenge; however, this does not mean paint removal, whether on concrete floors or walls, is impossible.
Liquid Paint Strippers
Whether used only for spot removal, such as for accidental paint spills, or completely stripping off paint on a concrete surface in preparation for repainting, chemical paint strippers will get the job done. However, it is not as easy as removing paint on wood.
Choosing the right kind of paint stripper for a concrete surface will mainly depend on the type of paint used, as all three types can be applied on concrete without causing damage. Use caustic strippers for epoxy, polyurethane, polyurea, polyaspartic, and acrylic coating or paints, which are commonly used on concrete, while oil-based paint are easily removed by solvent strippers. Biochemical strippers can also work with different types of paint on concrete, but the entire process will still take longer.
Sometimes, these paint strippers may not be enough to remove paint because of the porous nature of concrete, even if thick layers of it are applied over the paint. In such instances, additives that will make the chemicals absorbent at the same time may be used. Ordinary cat litter or clay, which is crushed up to become fine, will work well. They must be mixed together with the paint stripper before application.
Do note that reapplication of paint strippers may be necessary to completely remove paint on concrete.
Sanding may also be used for concrete paint removal, but normally only for floors. A sanding disc is attached to a standard floor buffer instead of a polisher, and the paint is remove in the same manner of polishing the floor.
While this method can be effective in removing paint that has gone deep into the holes of concrete, it is also known to damage the surface because of the scrapes and scratches it can create. That is why polishing the floors after stripping the paint off and before applying a new coat of paint may be necessary.
Another method of removing paint on concrete that may be considered less invasive is through power washing. Since water-based paint is typically used on concrete, power washing alone may be enough to remove it; there is no need to apply a coat of remover over the paint before attempting to wash it off using the pressure washer.
In case water is not enough to remove the paint, even at the highest pressure available, more abrasive washers, either a shotblaster or sandblaster, may be used. They work the same way as a pressure washer but instead of water, a shotblaster uses tiny beads made of metal and a sandblaster uses sand to remove paint. Since they are very abrasive, they must be used carefully to minimize any damage to concrete.
Paint removal on concrete surfaces is definitely more challenging, thanks to its porous nature.
Best Paint Stripper for Masonry & Brick
Making sure that every nook and cranny of an uneven surface, such as brick and different kinds of masonry, is evenly painted can be quite the challenge, but it is even more so when it comes to paint removal. That is why among those that were discussed, this is the surface that is hardest to strip paint off. Finding the best paint stripper for masonry and brick is not easy, especially if preservation is also a major concern.
Liquid Paint Strippers
To preserve brick and masonry, especially for historic homes, it is important to use the least obtrusive methods, that is why using liquid paint strippers should be done cautiously. These chemicals may have a strong reaction to the surface that can cause permanent discoloration, especially for older masonry and brick.
So, when using liquid removers, only those that are specially formulated for brick and masonry surfaces should be used. Caustic, solvent, and biochemical strippers may work, but make sure to get those intended for use on these surfaces. Caustic strippers should also be the last option, as it can be absorbed by the porous surface and cause long term damage that may not be instantly visible. Certain solvent paint strippers are water-soluble, and these are the best for masonry and brick.
Too often, liquid strippers will not immediately remove paint on masonry and brick, that is why multiple applications are usually done. Again, this should be done with caution to avoid any possible damage.
If the paint on masonry and brick is already in poor condition, power washing may easily remove the paint. However, this method may not be advisable for soft or weak bricks and masonry, which is typical for old homes. The water pressure, even at the lowest setting, may be too strong for the surface to withstand, that is why it is typically used only when other methods do not work.
Using sandblasters may also work, but these are a lot more abrasive than water. This means it can easily damage the surface if done improperly.
Given that both liquid strippers and pressure washers may damage a masonry or brick surface, some may think twice about using them. A less intrusive but very time-consuming method is by applying paint remover of the paste or gel kind on fabric and placing it over the surface. This allows paint to be transferred to the fabric, minimizing the possibility of damage to brick or masonry.
Paint Stripping Gel
A relatively newer method of removing paint is by using a paint stripping gel. This is considered as the most versatile way of doing so, because its formulation allows it to be evenly applied on various surfaces, even vertical ones. This can also be safely used on metals like aluminum, wood, masonry, brick, and even for antique furniture, like the Jasco Premium Paint and Epoxy Remover, but it may not properly remove paint on plastic surfaces.
Given enough time, from just a few minutes to as much as 24 hours, the paint will bubble up, indicating that it has separated from the surface and is ready to be wiped off. Its longer dwelling time will allow it to penetrate even thick layers of paint in a single application. While paint is normally scraped off, paint stripping gel will allow it to be easily wiped off.
Paint stripping gels can be used to remove different kinds of paint safely, including both water-based and oil-based ones and even lead-based paint. This is because it can encapsulate lead, trapping it to the gel and preventing it from being released in the air. It does not contain toxic chemicals commonly found in liquid removers, especially methylene chloride. However, some of them may contain NMP that is known to also cause health issues. Also, some are known to be odor-free, while there are also those that emit strong fumes.
From all these, it is safe to say that each of these paint stripping methods have their own set of pros and cons. it is up to the user to decide what would best meet his or her needs.
What should be remembered is that all of them will require the use of safety equipment, such as safety goggles, proper gloves, masks, and overalls or long shirts and pants. Even paint strippers that are marketed as safe or non-toxic may still contain toxic chemicals or compounds, and it is always better to be safe than sorry when removing paint in any surface.