We get the “Seal or Not-to-Seal” question all the time; even worse, we see it regularly being done improperly. Many folks think that all moldy surfaces need a “good cover-up” when in reality, all they are doing is making things worse. From giving the organism the moisture, it needs to grow to create “microbial resistant” strains of mold, understanding the mold remediation process is essential.
What Is a Mold Sealant?
A Sealant is like thick paint but with an antimicrobial mixed in. They are applied like paint and come in an array of colors, white being the most common. In theory, the encapsulant is supposed to seal up the organic food source (like wood), inhibiting future mold growth and reproduction. The process is called “Encapsulation.”
Picture of the flood-prone home where the crawl space & lower level were encapsulated. Challenge is getting all the gaps and cracks sealed, which is almost impossible to accomplish.
When Is Encapsulation Necessary?
It has been our experience that if moisture is properly controlled, encapsulation should not be necessary. But if it was to be needed, it would be in an area where moisture management continues to present a challenge (such as a crawl space or basement) or where materials can’t be replaced. You can learn more about the entire mold remediation and encapsulation process here.
Addressing the liquid water in this basement would be the first thing to address with this water/mold management strategy.
Mold Encapsulation Risks
Proper mold removal and moisture management are critical to any mold remediation job. Solve the moisture issue, mold can be effectively managed. If you can’t manage the moisture, don’t use an encapsulant, as it will always find a way to get around your moisture barrier. We have a saying in the office, “water always wins.”
- Hidden Mold – Moisture will get behind the encapsulant and stimulate mold growth that will bleed through the painted surface. Removing mold is a challenge, to begin with. Try getting it off when it’s growing under the sealant. This type of condition creates “hidden mold growth,” which is almost impossible to correct totally.
- Natural Wood Properties – All wood is “hygroscopic,” meaning it absorbs moisture from the surrounding air. It will find a way to equalize with the surrounding relative humidity regardless of being encapsulated. There are always going to be pin-hole gaps in your encapsulated wood, allowing moisture and molds to get in.
- Paint Over – Many times, molds will be “painted over” during a remediation encapsulation. This creates a hidden mold burden that will not stop molds from growing and often amplifies its effects. Be wary of encapsulated mold projects where moisture management and good ventilation are also being addressed.
- Chemical Burden – And if you have a chemical sensitivity, adding an encapsulant may add to your already stressed chemical burden.
Seal or not-to-seal? This home has very moist soils, and the crawl space was encapsulated 10 years earlier. Joists at 18. 9%mc and have succumbed to moist conditions requiring “sistering” of joists due to biodeterioration. The sealant was incomplete + mold-breaking through in many areas, as evidenced by yellowish and dark blotches. A total of 19 joists and structural beams were installed and not sealed. Post-installation sealing is not practical due to sistered beams. This is a tough space to manage.
Ask a Mold Professional
Removing mold is not like changing a light bulb. And dealing with encapsulants just complicates things even more. Having a Mold-Pro on your team would be an effective use of your budget and a good idea to help you design your customized mold management project. In trying to find a Mold-Pro in your area, try the internet and look at non-biased testimonials on Google for customers to share their experiences. That should give you a good idea of what the Firm is like to work with.
