This post will not be useful for everyone, but I've had a few requests for this tutorial and I hope that by putting it out there on the web it will be useful to some of my readers, old and new.
How to Re-Waterproof PUL on Pocket Diapers
A picture is worth a thousand words, right? After buying about 18 diapers in poor condition that leaked after only a few uses (I was so ignorant in those days!), I was determined to find a way to refurbish them. I could only find vague references to how to waterproof the PUL again, so after some trial and error (i.e. - 1 failed diaper and 17 successes), I am posting my method here in hopes that someone else can benefit. The spray is in an orange can labeled "Silicone Water Guard" and you can find it in the camping section at Wal-mart. It cost about $4 a can as of 2009. This can lasted for 1 pail liner (required a TON of spray) and 18 diapers. Not too bad really.
For the record, I have used this method on Fuzzi Bunz sized diapers and Swaddlebees Econappis. These two brands are my very favorite because they are easily repaired, both with the waterproof spray and by replacing the leg elastic.
Trace a pattern for your diaper on lightweight cardboard - cereal boxes work great! Turn diaper inside-out.
Stuff the cardboard in the diaper. Watch the sides - keep fleece underneath the cardboard, PUL on top. Find your waterproofing spray - available at Wal-mart in the camping/sporting goods section.
Go outside on a sunny day. Lay out a sheet of wax paper underneath each diaper. Spray a light coating on all PUL surfaces.
Let the coating sit for just a minute, then tip the diapers on their sides to allow any excess spray to run off the side into the grass. Fold your wax paper in half (keeping any excess spray on the inside) and lay the diaper on top to dry.
After a couple of hours, when the spray seems to be dry, remove the cardboard and hang the diapers outside to dry a little longer. Allow them to dry for at least 24 hours before washing or using them.
Turn your diaper right side out again and you should have a nicely re-waterproofed diaper!
Some FAQ's -
Q - What is PUL?
A - Polyurethane Laminate Wiki
Q - How do you know when the PUL needs re-waterproofing?
A - It's most obvious when you can see visible cracking in the PUL. Before trying the spray, I try running them through the dryer on high heat to reseal the PUL. This has worked with my newer diapers just fine. With the diapers that needed the spray, the wet was going right through the center, not just the edges around the legs. Other diapers that have leaked around the legs were just in need of stripping or needed changing sooner.
Q - Do I need to hang them outside to dry?
A - No, but they tend to be "fumey" for a few hours, so I recommend it. If you hang them indoors, use a well-ventilated room. Sometimes I hung them in the basement to dry.
Q - Do they drip after you hang them?
A - No, they shouldn't drip at all while hanging - they only seem to drip when you first spray them if it puddles up a bit - that's why I let the excess run off.
Q - Do I need to wash them before using them?
A - I don't think you really NEED to wash them before using them, though I prefer to do it. (The fleece doesn't come into contact with the spray at all.) If you have a baby with eczema, sensitive skin, or prone to diaper rash, I would just in case.
Other Cloth Diaper Tutorials -
How to sew microfiber inserts for pocket diapers
How to replace leg elastic
How to sew a waterproof pail liner