Should I use TSP to clean my furniture before painting? In the painting community there can be a fair bit of controversy surrounding TSP cleaners and their continued usage when there are so many highly regarded alternatives in today's market.
TSP stands for Trisodium Phosphate and it is a popular and commonly recommended surface preparation cleaner for painting. TSP can be purchased as a powder that you dissolve in water or as a ready to use spray. There are various trisodium phosphate cleaners available that are marketed under other names as well - these will list trisodium phosphate as one of their main ingredients.
For more than half a century, TSP has been used as a heavy duty cleaning agent. TSP was once a popular ingredient in a variety of soaps, laundry detergents and other consumer-grade cleaning solutions. The versatility and low cost of manufacturing TSP made it an obvious ingredient choice. Trisodium phosphate is still sold and used for cleaning, however, in most household cleaning products phosphates are no longer a significant ingredient. The overall popularity of TSP has diminished due to awareness of its harmful effects on the environment. Phosphates aren't "toxic" to the environment in the way that you may think. They do not poison wildlife but rather they cause water quality problems by creating nutrient pollution. Phosphates enter our water systems, enriching them with unnatural levels of minerals and nutrients, this in turn creates favorable conditions for the formation of harmful algal blooms. These algal blooms prevent light and oxygen from entering the water killing off important organisms and throwing off the balance of the ecosystem.
So the obvious question becomes: If phosphates are not being commonly used in products anymore, should we still be using TSP for prepping furniture? Below I have further explained the purpose of TSP as it relates to painting, as well as proper handling instructions for using it safely so you can make an informed decision on whether or not you choose to use it as a cleaner.
Safe TSP Handling
TSP is a heavy duty cleaner. If used incorrectly, TSP can cause skin irritation and even burns.
Avoid direct contact between TSP and bare skin - wear rubber gloves and long sleeves when working with trisodium phosphate. If skin contact occurs, wash thoroughly with soap and water.
Protect your eyes from potential exposure to TSP by wearing safety goggles. It is not uncommon to splash a bucket of cleaning solution in your face when washing walls or even furniture. If eye contact occurs, flush with clean water for at least 15 minutes and seek medical attention.
Protecting Surfaces You Aren’t Painting
When you are using trisodium phosphate cleaners, it is important to protect other surfaces from splashes. Painted surfaces, finished wood (such as hardwood flooring), and metals (furniture hardware) can be discolored or de-glossed by TSP. Be sure to cover or mask off anything you don’t want damaged.
Although the primary use for trisodium phosphate is cleaning, its alkaline properties make TSP an ideal degreaser, perfect for removing heavy grease and oil from various, even porous, surfaces. If you are looking to paint kitchen walls or cabinets, particularly those near a stove, you will need to clean away any greasy residues. This step is crucial, any grease that isn't removed prior to painting can adversely affect your paint's adherence. Before I paint any surface, kitchen or not, I always clean with a degreasing product. There are phosphate free degreasing alternatives on the market, like LA's Totally Awesome Cleaner, and I use them successfully on a regular basis. That being said when it comes to heavy, built up grease, there are few alternatives that work as effectively as TSP. If I am working on cabinets or kitchen furniture, my preferred cleaner is still a TSP solution.
TSP can also be used to de-gloss shiny surfaces, providing "tooth" so your newly applied paint has something to grab onto. When your walls or furniture have been previously painted with a high-sheen paint or sealer (satin, semi-gloss, or high gloss), you need to "dull" that sheen before applying another coat of paint. The slipperiness of glossy paints doesn't allow the next coat to stick, and your new finish may crack, peel or even drip. The quality of your paint job is only as good as your preparation and proper cleaning and sanding are imperative. Cleaning your projects with a TSP solution help to dull the surface similar to a light sanding.
So if TSP is so bad for the environment, why not just sand your surface instead of de-glossing with chemicals?
Good question! And you can! But what if you're painting 2000sqft of house, previously painted in a semi-gloss finish? Or maybe just a two story entryway with 30' ceilings? Sometimes a de-glossing agent is the easier, more cost effective choice. However for the purpose of de-glossing TSP would not be my first choice. There are several products on the market, such as Krud Kutter's Gloss-off, that can be successfully used instead of TSP.
Once you have completed your cleaning and/or de-glossing process you must always rinse your surface with clean water. Using a new, clean rag or sponge and a bucket of clean water (changed frequently for large projects such as walls), it is important to rinse away TSP, or any other cleaners, from your furniture and allow the surfaces to dry prior to painting. TSP residues left behind will not allow your new paint to adhere properly. Improper rinsing of TSP cleaning products is so common that many companies have started to include the warning "do not clean with TSP" in their product labels to prevent their products from failing.
Once I educated myself on phosphates it became my personal preference not to use them for most applications however based on my own trial and error, my experience still tells me there is a time and place for TSP. What are your thoughts on trisodium phosphates?
DISCLAIMER: This is not sponsored content. This is a personal review and the opinions, beliefs and viewpoints expressed herein are strictly my own. I did not receive financial compensation from any of the brands mentioned in this post.