What are taped seams – and are they important?

A person in a waterproof jacket looking out to the horizon (Image credit: Getty)

If you’ve spent any time shopping for wet-weather gear, tents or tarps, the chances are you’ve already come across the term “taped seams”. But what are taped seams, exactly? And why are they such a big deal in outdoor attire and gear?

In this article, we reveal all you need to know about seam sealing, from how the sealing’s done and why it’s necessary all the way through to the role sealed seams play in keeping you dry on your hiking and camping adventures.

What are taped seams? A definition

In short, seam taping is a method employed by outdoor gear manufacturers – in everything from the best tents and best waterproof jackets to gaiters and tarps – to improve waterproofing in gear by doubling down on protection in the fabric’s most significant point of weakness, i.e. the seams. When any product is made with multiple pieces of fabric, the pieces are sewn together, thus creating a “seam”. In the process of stitching the pieces of fabric together, hundreds – if not thousands – of tiny holes are created, thus leaving a potential entry point for water. Back in the day, outdoors-goers got around this problem by applying water-resistant waxes and oils to the seams, but seam taping is more effective, more durable, and saves you both a lot of hassle and having to put up with the (usually) funky smells of those oils and waxes.

A tent with water droplets running off it (Image credit: Getty)

There are three different types of taped seams: critically taped seams, fully taped seams, and welded seams.

Critically taped seams

This means that only portions of the seams or certain seams in the product are sealed, usually in the area most prone to leaks. Generally speaking, this is the lowest form of seal sealing because it is the least comprehensive and, thus, the least effective.

Fully taped seams

If any garment or product has “fully taped seams,” it means that every seam on it is – as the name suggests – sealed with tapes. As you might expect, this is the most effective form of seam sealing.

Welded seams

These are seams that are “welded” together by essentially melting the two pieces of fabric to create a tight, waterproof bond. The main benefit of welded seams is that the bond is often stronger than the original fabric and – unlike tape – the weld doesn’t require reapplication.

People trekking in waterproof jackets (Image credit: Getty)

Seam taping: how it’s done

During the production process, manufacturers tape the seams on products by applying thermoplastic tape to the seam with heat and pressure. The application of heat effectively melts the tape over the join where the two pieces of fabric are sewn together to create a waterproof seal.

It is possible to do a DIY job on your waterproof gear’s seams if they start leaking. All you have to do is pick up a roll of waterproof seam tape, apply this to the leaky seam, and then replicate the factory sealing process by applying heat with the tip of a medium-hot iron. Alternatively, you can use liquid-based sealants like the Gear Aid Seam Grip+ SIL. (opens in new tab)

Former Advnture editor Kieran is a climber, mountaineer, and author who divides his time between the Italian Alps, the US, and his native Scotland.

He has climbed a handful of 6000ers in the Himalayas, 4000ers in the Alps, 14ers in the US, and loves nothing more than a good long-distance wander in the wilderness. He climbs when he should be writing, writes when he should be sleeping, has fun always.

Kieran is the author of 'Climbing the Walls (opens in new tab)', an exploration of the mental health benefits of climbing, mountaineering, and the great outdoors.