All About Function

June 08, 2023


At Rainbird we have a firm focus on selecting beautiful fabrics that are deceptive in what they provide: waterproof, breathable, durable and soft to touch.

Why Waterproof

Clothing that can repel water is a core function vital to making sure you can be outdoors for longer in comfort and style.
The technology of our fabrics means water that lands on the outer jacket won’t pass through the fabric. This is achieved via a clever membrane layer that’s laminated to the fabric which has teeny tiny pores that prevent water molecules from passing through, but (thanks to fancy fabric technology) it allows moisture vapour (ie your sweat) to be released through it at the same time.

How is this tested you ask? Well, we use the Hydrostatic Head Test. Our chief fabric testers take a cutting from the fabric and clamp it to the base of a clear tube. The tube has millimetre measurements marked on it and the tube will then be filled with water. The fabric tester closely monitors it to see how high the tube can be filled with water before small droplets of water seep through the fabric. It’s at this point a reading is taken of how high the water column is. This number equates to the waterproof rating.

When shopping our products you’ll see under Features & Specs, some numbers that look something like this: 8,000mm / 5,000mpv
The “mm” number relates to how many millimetres of water the fabric could withstand before it penetrated the fabric. The “mvp” number stands for Moisture Vapor Permeability – which is how breathability is measured. We have all of our laboratory ratings ratified by a governing board to give you (and us) piece of mind that you’re buying into quality and durable products. We test to Australian & New Zealand standards.

What does breathability mean?

The breathability factor helps regulate your body temperature. We measure this rating on all of our garments through the testing of how many grams of water vapour can pass through a square meter of fabric from the inside to the outside in a 24 hour period. In every day language, we’re talking about your sweat. This will always depend on what you’re doing, whether it’s grabbing a coffee, hiking in the Grampians or cycling to work. Regardless of what Mother Nature is gracing us with that day, be it raining, snowing or glorious sunshine we’re all humans – so we sweat. What you need in your jacket is a high level of breathability. This can be achieved easily when fabric (like ours) can draw the vapour molecules out to the surface of the jacket, and release them outside. The evaporation of sweat and dissipation of vapour is necessary to regulate body temperature. Happy body = happy mind = happy days! We’re sure our sweat likes that it can escape confinement too!

Fabrics that breathe provide high comfort and convenience for the wearer – which means that looking good and feeling great aren’t compromised by the weather. At Rainbird we combine our innovative fabrics to be both Waterproof & Breathable through layering the fabric with a Micro-porous membrane in 3 steps.
1. Outer layer (which we call the face fabric) will usually have a DWR (durable water repellent) finish applied. This helps Raindrops roll off the material, rather than soak in.
2. An inner layer (which is either a laminated membrane bonded to the face fabric or a coating which is a liquid applied to the interior of the garment). This is the clever membrane that keeps raindrops out, but lets your sweat breakout.
3. A crucial backing layer or garment lining. This will come in the form of a very fine mesh like layer. Its job is to protect the inner membrane layer and also keep the wearer super comfortable.
So hey presto we hear you shout?! Um…unfortunately not. Even though a garment may be labelled as waterproof & breathable… there is still one key element missing. Seam Sealing… keep reading to learn more.

What is seam sealing?

When a garment is made it needs to be sewed together. Every seam that’s stitched will puncture minuscule holes into the fabric and membrane. If this isn’t sealed, then water can easily get through! When the water gets through, that means you’ve got a soggy day ahead… To avoid an uncomfortable outing in the wet weather, we apply a process called seam sealing. This process makes sure no water gets through those holes created by the stitching. We fully seam seal all of our products … so not just one or two seams. We mean every seam you see on that garment! This pretty much invisible method is done via a heat sealing tape that is run over the seams.
The result? You’ll stay nice and dry on the inside throughout the day!

Quiet Fabric

Now this may be one not many think of, but don’t worry for we have! Frequently, waterproof garments have a coating applied to increase its waterproof ratings. More often than not, this results in a crunchy, noisy outcome.
We’ve carefully selected a specific high-quality lamination process instead, this innovative fabric won’t be intrusively crunching and crumpling as you walk, it’s our very own ‘quiet fabric’ doing just as it says – reducing the sound so you can enjoy the elements in peace and quiet. Once we’ve selected all of the best quality fabrics and processes we apply our technical knowledge to the design features of the garment. These details make sure living your every day life in a Rainbird product is sublimely comfortable.

Some Extras!

Adjustable Cords & Cuffs – With carefully hidden tie adjustments, you can make sure your jacket fits you ‘just-right’. Coupled with adjustable cuffs too this ensures the cold stays out and the warm stays in!
Stay-Dry Hood – Our unique hood has been crafted to protect you from the elements, some come with an added ‘peak’ to give you the extra cover needed come rain, wind or shine. We all come in different shapes & sizes so our hoods are often height adjustable and come with cinching cords too.
Storm Flaps & Garages – Sometimes the wind & rain are just desperate to get in – wherever it can. We integrate storm flap protectors on zippers and pockets to protect you from the weather creeping in where it can. We also have garages at the top of the pocket zips for you to park your zippers in to shield this little gap from the weather, and prevent leakage into your pockets.

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