I owe a word of thanks to user “Ellyn,” whose comment gave me the idea for today’s post:
If one wears two disposable diapers, both with waterproof backing, how does that increase absorbency?
An excellent question, Ellyn!
The short answer is that it doesn’t, much. Taping one disposable diaper on over another is not a very efficient use of your supply.
But it’s also not wholly irrational, and here’s why:
1. Properly Doubled Diapers Prevent Leg Leaks
This is the most effective use of “doubling” diapers: if the second diaper is taped lower on the legs than the first, and the gathers are secure, it will create a new barrier to leakage around the thighs.
In this model you’re essentially using a disposable diaper in place of plastic or rubber briefs. The padding won’t get too much of a workout, though some of the leakage from the first diaper will soak into it, but you’ll gain another hour or two of protection for the most common failure point of a disposable.
It’s inefficient, and a waste compared to just wearing plastic or rubber briefs, but if you don’t have those handy it can work for you, and some people may find it more comfortable as well.
2. Slitted Diapers Can Make Use of Doubled Padding
This is an old trick that’s popular with diaper fetishists who prefer to go as long as possible between changes: by taking a pair of scissors and cutting a long slit down the middle of one diaper, waistband to waistband, and then putting on both that diaper and a second one on top of it, you essentially create a single diaper with two layers of padding.
Like all DIY tweaks, though, this has some inevitable flaws. Diaper stuffing, freed from its plastic shell, is messy stuff — dry, it’s a powdery fiber that floats in the air and can irritate your eyes and mucus membranes; wet it becomes tiny, pebbly globules that will spill all over the place if they escape the second diaper. (They can also clog drains, so be careful with them around your bathtub).
It’s also not a fully efficient use of the second diaper. The aforementioned globules will sink down into the outer diaper’s padding, and slowly leak moisture into it but the material is designed to absorb a stream of liquid, not to blot moisture out of another porous object. The loose material from the inner diaper is likely to spread out, saturate the leg gathers of the outer diaper, and cause leaking long before the central pad of the outer diaper has reached its capacity.
3. Some People Just Like It
For people who get plewp_e from the sensation of wearing a diaper, lots and lots of thick padding and crinkling plastic is a fun thing. It doesn’t have to be an efficient or effective use of materials to get this benefit — if you like the overstuffed feeling of layered diapers, you like it, and it doesn’t matter that much if the outer layers aren’t serving much of a useful purpose.
The more effective alternatives (diaper stuffers, either cloth or disposable) won’t necessarily provide that same exaggerated babyishness, which is probably why the doubled-diaper strategy is never going to go away completely.
And that’s why some people double up their diapers!