PUL stands for 'polyurethane laminated' and it’s a type of waterproofing fabric used in cloth diapers and wet bags. I have a post where I show how you can purchase PUL at a fabric store and use it to make your own wet bag (aff link)! PUL has properties like elastic and rubber, which combine to give fabric a flexibility and waterproofing. If there is a problem with the PUL layer in diapers or wet bags, it can jeopardize waterproofing. I wanted to mention a little more about PUL: specifically, I'll address what it should and shouldn't look like and how to care for it.
We learned a lot about PUL problems in 2010 when we discovered we had a bad batch of pocket diapers. I began noticing the PUL layer bubbling up across the back of many of our diaper covers. It looked like a plastic layer separating from the colored shell of the diaper. Since the PUL had separated, it really increased the risk of it catching on something and tearing, or possibly even cracking. We had only been using the diapers for a few months, and I had been line drying the diaper shells 90% of the time.
I immediately went onto the company website and checked the warranty of the diapers. PUL problems were covered for 1 year. We were able to return the diapers to the company and they sent replacement diapers plus some freebies to cover our cost of shipping. We discovered that this company had a period of major PUL problems resulting from bad craftsmanship at their plant.
Cloth diaper manufacturers are not alone in experiencing PUL problems--even wet bags can become "delaminated" (separation of PUL and fabric) and rip. In the image shown, a delaminated wetbag was used for months before it finally tore. We continue to use the wet bag despite the damage (which is near the top of the bag). Well-made PUL should last for a very long time without experiencing these issues. Most of our cloth diapers have lasted over four years without experiencing any delamination.
PUL comes in many colors and textures, so don't be worried if the waterproofing on your diapers seems to look different than other images of PUL. For example, PUL may have large, honeycomb-style texture or almost no texture.
You can help keep the PUL layers of your diapers and wetbags looking nice by line drying your diapers whenever possible. Think about T-shirts with plastic embellishments on them--if you put them into a hot drier, the design tends to crack (unless you turn T-shirts inside out). This is because even on low, a dryer still gets pretty hot for plastic material. I would also recommend not using homemade detergents on your cloth diapers and wetbags because acidity levels or the chemical composition could be too harsh for the delicate PUL layer. Do not use vinegar or baking soda in your wash. Using vinegar once or twice might be fine, but repeated use of vinegar can damage PUL and elastic.
Have you checked your cloth diaper or wetbag PUL to see what it looks like?
Kelly's Closet link is an affiliate link.