Removal of thick layers of paint off wood is a challenge for many homeowners, especially if their homes were painted before 1978. Until that time, much of the paint used on homes was lead-based. In 1978 federal laws were enacted in the U.S. prohibiting the use of lead-based paint in housing. Lead paint fumes, dust, chips and other paint waste can pose serious health hazards if not taken care of properly. So, the removal of lead-based paint can be quite dangerous for children and adults. All lead-paint removal methods require significant safety measures to assure the health of the workers and our environment.
The traditional methods for paint removal include: heat guns and heat plates, sanding, shaving, chemical – both toxic and non-toxic, and pressure washing. The costs for these different methods vary greatly. All methods of paint removal are labor intensive. The financial costs of paint removal should consider not only the materials and equipment, labor including set-up, actual time using the method, clean-up and waiting time but also the costs of safety measures to lower the risks to the workers, environment, and the wood itself.
In the late 1980’s a safer and more eco-friendly method was developed in Sweden by a restoration specialist. This method uses mid-range infrared heat waves to heat both the wood and the paint at a lower temperature. Therefore, it greatly reduces the hazards of removing lead-based paint in three ways:
1) Metallic lead vaporizes at 1100°F. which is the temperature at which heat guns operate. Lead oxide used in paint most likely vaporizes at about 800º F. The mid-range infrared heat waves heat the paint and wood only to 400-600º F. Therefore, dangerous lead fumes are not released from the heated paint.
2) The scraping of the softened paint does not generate dust as does dry scraping, sanding, or shaving. Containing lead dust is difficult and costly but very important to keep the lead out of user’s lungs and out of the environment.
3) The soft paint scrapings clump together and drop onto a tarp which makes them easier to capture and faster to clean-up. Pressure washing tends to leave the water with paint chips remaining in the work area’s soil making it difficult to clean up without removing the top soil itself. No messy goo is created by this infrared heat method as is usually created with the use of toxic or non-toxic chemical paint removers.
Another key consideration in paint removal is the impact of the method on the wood. Chemicals can leach out natural resins and leave a residue in the wood even after it has been rinsed or neutralized. High heat (1100ºF.) from heat guns can force the paint pigment back into the wood and as well as scorch the wood. Sanding and shaving can leave gouge marks and even scorch marks if not done by a skilled technician. Pressure washing drives moisture back into the wood and can also leave gouge marks in the wood.
Infrared heat paint removal can be the gentlest process on the wood. This is particularly beneficial for historic properties where preservation of the original, old wood is desired. The infrared heat penetrates into the wood and actually pulls up the natural resins deep in the wood to rejuvenate it. It also pulls up the paint or varnish which has sunk into the wood allowing them to be scraped off more thoroughly. The heat removes extra moisture deep in the wood and neutralizes mildew and fungus. Yet, the lower temperature at 400-600° F. minimizes the risk of scorching the wood or catching it on fire.
With the infrared heat method the wood is immediately ready for application of a primer paint. Little if any sanding is necessary on the wood surfaces which have been heated and scraped using the infrared heat method. There is no waiting time for drying or neutralization. The heated wood is immediately dry enough to receive primer. In fact, it is preferable to do this priming within hours of scraping to assure ambient moisture does not seep back into the wood.
There are, however, some less frequently used paints which do not react to the infrared heat process. Milk, protein, or blood paint and stains usually have penetrated into the grain of the wood and are not easily separated from the wood. Shellac reacts similarly. On rare occasions, some other chemical compounds added to the paint such as those used in Kilz for mold retardants or an abrasive to prevent slippage on a painted floor may interfere with the separation of the bottom layer of paint from the wood by the infrared heat.
While the infrared heat paint removal method has been used extensively in Europe for almost ten years, it is a new technology in the U.S. for the past several years. Most painters and paint retailers are unfamiliar with the technology. Historic preservationists and homeowners of older homes are most often interested in the infrared method for its time-saving steps, safety features, low environmental impact, and benefit to the old wood.
Find out more about infrared heat products that remove paint, especially for lead-based paint. As with most products, their features vary. Look for machines that provide the following features:
- Increased efficiency by heating a significant area thoroughly with just one application.
- Two infrared bulbs are better than one.
- Built-in safety shields extending below the infrared bulbs that easily set for the operator the correct distance between the bulbs and the painted wood. These shields should eliminate the operator’s guesswork about what distance is safe yet effective and reduce the risk of overheating.
- Infrared heat using mid-range, infrared wavelengths to heat the wood and the paint at a lower temperature to prevent scorching, fire, and lead fume emission.
- An automatic, overheat shut-off mechanism to prevent damage to the machine.
- Comprehensive instruction materials and training to assure quick operator proficiency and safe operation and maintenance of the machine.
This article is provided courtesy of Eco-Strip, LLC. For more information on the infrared heat paint removal process, go to www.eco-strip.com.