Waterproofing faux leather boots, and whether it works

The surface of a faux leather boot is a polymer film, and water does not pass through a polymer film. That means the thing most people try to waterproof is already the driest part of the boot. Water gets in at the seams, through the lace throat, up through the sole join and down the inside of the shaft, and most of the products sold for the job do nothing about any of that. What follows is which treatments have an effect on a synthetic upper, which are a waste of money, and the two habits that make more difference than any spray.

Why the upper is not the problem

Faux leather is a woven or knitted backing cloth with a polyurethane or PVC coating bonded to the face. The coating is continuous and non porous. Rain sits on it in beads and wipes off, which is the one genuine advantage synthetic uppers have over hide.

Real leather is different. It is a porous material that drinks water, swells, and dries stiff and pale unless it is conditioned, which is why the leather care aisle is full of waxes and creams. Those products exist to solve a problem your boots do not have.

So when a faux leather boot lets water in, the water came through a hole, not through the material. Finding the hole is the whole job.

Where water actually gets in

The sole join. On a cemented boot the outsole is glued to the upper, and that bond line is the first thing to open with flexing. A hairline gap at the ball of the foot, invisible until you look for it, will take on water from a shallow puddle in seconds.

The stitched seams. Every needle hole through a coated fabric is a channel. Factories use thread that swells slightly when wet and some use a sealant tape inside, but on a fashion boot you should assume the seams are not sealed.

The lace throat and the tongue. Water runs down the front of the shaft and in behind the tongue, which on most laced boots is a single unbacked panel with no gusset. This is how feet get wet in boots whose uppers are completely dry, and it is why gusseted tongues are worth looking for.

And the top of the shaft, if you are standing in rain for long enough or the boot is cut below the hem of your trousers.

What actually helps, in order

A seam sealant. A thin bead of clear flexible urethane seam sealer, the kind sold for tents and outdoor gear, run along the sole join and the main upper seams with a cotton bud, does the single most useful thing available to you. It stays flexible, it bonds to synthetics, and it is invisible on black. Do it on dry clean boots and let it cure overnight.

A silicone or fluoropolymer spray intended for synthetic footwear. On the coated face it does almost nothing, because there is nothing for it to soak into. What it does help with is the stitching, the lace throat and any exposed fabric panel or textile lining at the top of the shaft. Reapply after a few weeks of wear rather than once a season.

A pair of thick socks and a sensible route. Not a joke: on a boot that is sound at the seams, the realistic failure mode in heavy rain is water over the top, and no treatment addresses that.

What does nothing, or harm

Wax and dubbin. These are made to be worked into the open fibre structure of hide. On a coated upper they sit on the surface as a greasy film that collects dust, dulls the finish and transfers onto your trouser hems. They do not penetrate because there is nowhere to penetrate.

Leather conditioner and mink oil. Same problem. Worse, some solvent-carried conditioners soften a polyurethane coating, which is the opposite of what you want on a material that fails by cracking.

Heat. A hair dryer, a radiator or a car heater will dry a boot faster and shorten its life doing it, because the coating and the adhesive at the sole join both soften and then set differently. The Lace Up Boot and the rest of the synthetic boots we sell are glued at the sole, and heat is the quickest way to persuade that glue to let go.

After a soaking

Take the laces out and the insoles out. Wipe the outside down with a damp cloth before anything dries, because if the water carried road salt the salt is what damages the finish, not the water.

Stuff the boots loosely with newspaper or plain paper and change it after an hour, then again after three. Paper pulls moisture out of the lining faster than air alone and it holds the shaft upright while the boot dries so it does not dry with a crease folded into it.

Dry them at room temperature, away from any heat source, for a full day or two. Then put the insoles back. A boot that has been dried hot will often look fine and feel subtly wrong, because the footbed board has shrunk.

When a different boot is the answer

If you walk a mile in standing water every day, a fashion boot is the wrong tool whatever you spray on it. What you want is a boot with a gusseted tongue, a sealed membrane lining, and either a vulcanised or a stitched and sealed sole, and those features put a boot in a different price bracket and a different silhouette.

For most people, most of the time, the honest answer is that a sealed cemented boot handles rain, wet pavements and slush perfectly well and will fail eventually at the sole bond or at a flex crack in the upper, not from being rained on. The Work Boot with a flat sole and a low shaft is the easier of our shapes to keep dry, simply because there is less seam length and less shaft to run water down.

What we will not tell you is that any of them are waterproof. They are water resistant, they are glued, and the seams are not sealed from the factory. Seal them yourself and they are good for a wet winter.

Questions people actually ask

Do you need to waterproof faux leather boots?

The coated upper is already water resistant, so there is nothing to treat there. What benefits from treatment is the stitching, the lace throat and the sole join. A flexible seam sealant on those does far more than a spray on the surface.

Can you use wax or dubbin on faux leather?

No. Wax, dubbin and mink oil are designed to soak into hide. On a polyurethane coating they sit on top as a greasy film that attracts dust, and some solvent-based conditioners soften the coating, which encourages cracking.

How do you dry wet boots without damaging them?

At room temperature, with laces and insoles out and paper stuffed loosely inside and changed after an hour. Never on a radiator or with a hair dryer: heat softens the sole adhesive and the upper coating, and a glued boot can start to separate.

Are faux leather boots waterproof?

Water resistant, not waterproof. The material itself does not let water through, but the seams and the glued sole join are unsealed on most boots, and water runs in behind the tongue on anything laced.