The short version: check the fit first (snug legs and waist, no gaps), then check absorbency (enough capacity in the right spot), then check whether the diaper is repelling (inserts dry but leaks happening anyway). If none of those is the issue, the PUL waterproof layer may be failing — inspect the inside for cracks or delamination. Most leaks are fixable; a few mean it's time to replace the diaper.

Where to start based on what you're seeing

If you don't know where to begin, match what you're seeing to the most likely cause below, then jump to that section.

New cloth diapers haven't been prepped

Problem

Most natural-fiber cloth diapers — bamboo, hemp, cotton — need 3–5 wash-and-dry cycles before they reach full absorbency. The natural oils in the fibers have to be washed out before the fabric can soak up liquid properly. If your diapers are brand new and leaking, this is usually why.

Solution

Wash bamboo diapers with detergent at least once before first use. Hemp and cotton diapers can be used after one wash but don't hit peak absorbency until wash 4 or 5. Prepping is just repeated wash-and-dry cycles with regular detergent — nothing special required. Never boil EcoAble cloth diapers — boiling damages the fabric and any PUL or elastic.

Wrong size or poor fit

Problem

A cloth diaper needs to fit snugly with no gaps around the legs or waist. Too big and liquid slips out through the gaps before the absorbent core can catch it. Too small and the diaper can't hold what it's supposed to hold.

This applies to every age: a newborn in a size too big will leak, a toddler who's outgrown a size will leak, and an adult in a diaper cut for smaller body types will leak the same way.

Solution

Test fit by observation. For babies and kids: lay them on their back and gently move their legs in a crawling motion, watching the inside edges of the diaper. For adults: stand up, sit down, walk a few steps. In both cases, if the diaper gaps or opens at any point around the legs or waist, the issue is fit — not absorbency. Also make sure any absorbent insert is fully tucked inside; even a small corner sticking out wicks liquid to the outside.

If you're between sizes, try adjusting the rise snaps (for one-size diapers) before sizing up. For adults, check the measurement chart against your actual waist and thigh measurements — sizing varies significantly between brands.

Compression leaks

Problem

Too loose leaks around the legs. Too tight causes compression leaks — the pressure squeezes liquid back out of the absorbent layers. Microfiber inserts are especially prone to this; hemp and bamboo handle compression better. All-in-one diapers with built-in soakers can also compression-leak if over-stuffed.

Non-diaper sources of compression cause the same issue: car seat crotch buckles, swing harnesses, tight waistbands, skinny jeans, or sitting on firm chairs for long periods. This gets more pronounced with older and heavier wearers — a 40-pound toddler puts more pressure on the diaper than a 15-pound infant, and an adult puts more still.

Solution

Adjust the fit so the diaper is snug but not tight. Avoid over-stuffing pocket diapers — two slim inserts usually work better than one thick one. Wear looser clothing over the diaper. For car seat trips, use a more absorbent diaper or an added booster so the compressed capacity still handles the output. Switching from microfiber to hemp or bamboo inserts solves many compression leak problems.

Leaks through the PUL in front, middle, or back

Problem

Most all-in-one and pocket diapers have absorbent layers distributed evenly across the diaper. But output is rarely even — urine goes where the anatomy directs it. If one area soaks through while the rest of the diaper stays relatively dry, you have a positional absorbency problem: there isn't enough capacity where it's needed.

Solution

Add a booster or additional insert placed specifically in the problem area:

• Boys and men need more absorbency in the front of the diaper. If you're getting front leaks, add a booster in the front third. For infants, also make sure the penis is pointed down during diaper changes — if it points up, urine can travel straight out the top of the diaper without ever hitting the absorbent portion.
• Girls and women typically need more absorbency toward the middle, where the output lands.
• Babies close to sitting up but not quite there often need more absorbency in the back, since they spend more time reclined than fully flat.
• Adults who primarily stand or walk generally need more absorbency toward the front (for men) or middle (for women). Adults who spend most of the day sitting may need back-weighted absorbency to handle gravity pulling liquid rearward.

Side and belly sleepers

Problem

Pocket and all-in-one diapers have absorbent layers through the middle but not on the sides. When the wearer sleeps on their side or stomach, gravity pulls urine toward the side of the diaper — and if it reaches the edge before the absorbent core catches it, it leaks. This is one of the most common overnight leak causes for toddlers, big kids, and adults.

Solution

Switch to a diaper style with absorbency distributed all the way around rather than concentrated in the middle:

• Fitted diapers — absorbent through the whole diaper, including the sides. Used with a cover. Good for babies, big kids, and adults who are side sleepers.
• Flats or prefolds with a cover — similar all-over absorbency, often at a lower price point.
• Heavy-duty night diapers — designed specifically for long stretches and unusual sleep positions. EcoAble has dedicated night cloth diapers for babies and kids and adult night diapers.

For heavy wetters who are side sleepers, pair a fitted diaper with a wool or PUL cover and add a booster in the direction the wearer tends to roll toward.

Over-saturation / heavy wetters

Problem

Every diaper has a capacity limit. When it's full, it leaks — no matter how good the fit or how much you've spent on the diaper. The sign is obvious: the inserts come out completely soaked.

Capacity issues hit at different life stages. Babies between 3–12 months often have periods of heavy wetting. Toddlers who've started holding it longer between pees produce larger single outputs. Adults with incontinence may have anywhere from occasional small leaks to heavy ongoing output — and capacity needs scale accordingly.

Solution

Two approaches, often used together:

• Change more often. Daytime diapers should generally be changed every 2–3 hours whether they feel full or not. For adults managing incontinence, work out your own interval based on typical output — waiting until leaks happen is waiting too long.
• Add capacity. Stack a doubler or extra insert on top of the regular insert. Hemp and bamboo inserts hold the most liquid per volume — use them when microfiber isn't cutting it. For overnight or long stretches, use a dedicated night diaper designed for sustained output.

For adults specifically, the adult cloth diapers guide covers capacity planning by output level and what products work for heavy, medium, and light needs.

Old or worn-out inserts

Problem

Inserts don't last forever. Microfiber inserts typically last about a year of heavy rotation. Hemp and bamboo inserts last longer — often 2–3 years — but they do eventually lose capacity. If your diapers used to work and don't anymore, and you've ruled out repelling and PUL issues, the inserts are probably tired.

Solution

Replace them. Inserts are much cheaper than full diapers — usually $5–15 each — and a fresh set of inserts can make an old diaper system feel new again. Browse cloth diaper inserts for babies and kids, or adult inserts and boosters.

Repelling (the most common hidden cause)

Problem

If your diapers leak but the inserts come out barely damp or fully dry, the fabric is repelling — liquid is rolling off the fibers instead of soaking in. This is almost always caused by residue built up on the fibers from one of a few sources:

• Fabric softener or dryer sheets (used on the diapers, or residue from other loads coating the machine)
• Petroleum-based diaper creams — Desitin, Aquaphor, Vaseline, A&D, Balmex
• Heavy fragrance or dye residue from some detergents
• Improper wash routine that doesn't fully rinse detergent out
• Mineral buildup from hard water over time

Solution

Strip the diapers to remove the buildup. See the stripping guide for the full process — a 4–6 hour hot soak with RLR or a DIY mix of washing soda, borax, and Calgon, followed by a water-only rinse.

For severe buildup from petroleum-based cream, scrubbing the inner layer with a soft toothbrush before the strip helps break up the residue.

Then fix whatever caused the buildup in the first place so it doesn't come back:

• Switch to a cloth-diaper-safe cream (Granma El's, Earth Mama, California Baby) or use a disposable liner when using any cream.
• Eliminate fabric softener and dryer sheets from the household laundry — they coat the machine and transfer to diapers.
• Review your detergent against the cloth diaper safe detergents list.
• Add a water softener to every wash if you have hard water.

Weakened waterproof layer (PUL)

Problem

The PUL (polyurethane laminate) layer is what makes the outside of the diaper waterproof. Over time — or from mistreatment — it can crack, peel, or separate from the fabric. When PUL fails, liquid wicks straight through the outside of the diaper no matter how absorbent the inserts are.

PUL damage comes from a few places:

• Bleach, vinegar, or chemicals in stain removers used too often
• Washing or drying at very high temperatures repeatedly
• Fabric softener residue building up and breaking down the laminate
• Normal age — PUL typically lasts 2–3 years with proper care, sometimes more

Solution

Check the PUL by turning the diaper inside out and inspecting the inner side of the outer layer. You're looking for:

• Cracks or flaking in the laminate
• Areas where the laminate has separated from the fabric (delamination — feels bubbly or loose)
• Tears or holes

If the PUL is damaged, the diaper needs to be replaced — there's no reliable home repair. If the PUL looks intact, the leak issue is something else from this list (most likely positional absorbency or repelling).

Common questions

Fix the root cause

If you've worked through this guide and still can't solve leaks, contact us — we're happy to help troubleshoot or recommend a different diaper style for your situation. For warranty-related issues, see our warranty policy.