Waterwal bags are 2 cm thin and weigh 420 grams. Add water and each one becomes an
18 kilo barrier in about three minutes. No sand. No shovel. No storage unit.
Just a quiet answer to the question you'd rather not think about.
Ships flat · 10-year shelf life · Nothing to maintain
One doorway · six bags · under four minutes
0g
Dry weight of one bag
0kg
Weight once activated
0min
Average activation time
0yr
Shelf life, sealed
The honest version
Most people find out their plan doesn't work at 2 a.m.
Heavy rain arrives faster than it used to, and the traditional answer — sandbags — asks for
everything you don't have in that moment: sand, a shovel, a second pair of hands, and a warning
that came early enough to matter. Waterwal was built the other way around. It asks for nothing
until the day you need it.
The old way
Half a pallet of storage, all year round, for four nights of use
Roughly 420 kg to move by hand, in the rain, in the dark
You need sand on site before the water arrives — most people don't
Filling and stacking a single doorway takes two people about 45 minutes
With Waterwal
A pack of twenty fits in a shoebox, under the stairs or behind a filing cabinet
8.4 kg for that same pack — one person carries it in one hand
The floodwater itself activates them, so late warnings stop being fatal
One doorway, one person, about six minutes start to finish
How it works
Three steps. No training.
Inside each bag is a cross-linked polymer core that binds water and holds it as a gel.
That's the whole mechanism — and the reason it stays flat until the moment it's needed.
Lay them down
Take the bags out of the pack and lay them flat across the doorway, vent, or loading bay. They arrive folded and ready — there's nothing to assemble.
30 seconds
Add water
A hose, a bucket, or the floodwater already at your door. The core binds the water and each bag swells to around 18 kg, moulding itself to the ground beneath it.
3 minutes
Stack and walk away
Build up in layers, overlapping like brickwork. The weight and the seal do the rest. Afterwards the bags dry out slowly and go out with ordinary waste.
2 minutes
The unique bit
The protection is the easy part. The storage is why people never buy it.
Everybody agrees flood barriers are sensible. Almost nobody has room for them.
Here is the same doorway, protected both ways — drawn to scale.
Protecting one standard front door — 20 units, three layers high
Each square is the shelf space of one Waterwal pack — about a shoebox.
Where it's used
Homes, businesses, and the people who plan for both.
At home
Front and back doors, garage thresholds, cellar lights and air bricks. A home pack lives in a cupboard and takes less room than a winter coat.
For business
Shopfronts, loading bays, server rooms and lift shafts. Stock enough for the whole frontage without giving up a single pallet position.
In a response plan
Facilities teams, housing associations and municipalities keep packs in every building rather than one depot — because the depot is never where the water is.
Specification
Everything, on one page.
One bag. Figures are typical values for the standard unit; the business unit is listed separately in the datasheet.
Dry weight
420 g
Weight, activated
~18 kg
Dry dimensions
62 × 26 × 2 cm
Activated dimensions
62 × 26 × 11 cm
Activation time
3–5 min in fresh water
Absorbent core
Cross-linked sodium polyacrylate
Outer
Woven polypropylene, UV-stabilised
Shelf life
10 years, sealed and dry
Working range
−20 °C to 60 °C
Disposal
Air-dries, then general waste
Salt water
Reduced swell — use one extra layer
Reuse
Single flood event; dry storage between drills
In their words
The relief is the product.
“We'd been flooded twice. The third time we were ready in ten minutes and I slept through the night.”
Placeholder testimonialHomeowner · river valley
“Storage was the whole objection. Now every one of our sites holds its own kit in a cupboard.”
Placeholder testimonialFacilities manager · retail group
“It's the first thing I've bought that made the worry smaller instead of bigger.”
Placeholder testimonialCafé owner · town centre
Questions
Sensible things to ask.
Each activated bag is about 11 cm high. Stacked in overlapping layers, three layers give roughly 30 cm of protection, which covers the large majority of doorway flooding. Beyond about 50 cm you want an engineered barrier, and we'll tell you so rather than sell you more bags.
They divert and slow it. Like any sandbag-style barrier, a small amount will seep through and around; the point is to keep the bulk of it out of your rooms and buy you hours. Laying a plastic sheet under the first layer improves the seal considerably.
That's the useful part. The bags activate on contact with the incoming water, so laying them dry in the path of a rising flood still works. You don't need a hose, and you don't need to have been early.
Treat them as single-event. After a flood the bags have absorbed whatever the water was carrying, so they go out with general waste once dried. Unused bags kept dry stay ready for ten years.
The core is the same non-toxic super-absorbent polymer used in horticulture and hygiene products. It isn't food, but it isn't hazardous either. Follow local rules for disposal after contaminated floodwater.
Roughly two bags per metre of opening, per layer. A 1 m front door at three layers is six bags. There's a calculator on the buy page that does this for you, and you can send us a photo of your frontage if you'd rather we did it.
You can't move the weather. You can move this into a drawer.
Packs ship flat within two working days. Choose a size, or tell us your frontage and we'll work it out with you.