Is electrical tape waterproof?

Is electrical tape waterproof?

From warning tape and anti-slip tape to masking tape and PVC insulation tape, there is a raft of tapes available in today’s market. Our latest guide looks closely at one particular type and asks Is electrical tape waterproof?

Before we look at whether electrical tape is waterproof, we need to examine what it is!

What is electrical tape?

As the name implies, electrical tape is an adhesive tape used specifically to protect and insulate wires or cables capable of conducting electricity. Electrical tape can be manufactured from various materials, including cloth, mastic, rubber and PVC (polyvinyl chloride). At cableties-online, the electrical tape we stock is PVC insulation tape that is available in all the popular, industry recognised colours.

Waterproof versus water resistant

The terms waterproof and water resistant are often used interchangeably with each other when, in fact, they mean different things. The dictionary definition of waterproof is to be ‘impervious to water’, so that a material that is waterproof ‘prevents permeation by water’. By contrast, water resistant is defined as a ‘material that is able to resist water penetration to a certain degree, but not completely’.

Is electrical tape waterproof?

Based on the above definitions, electrical tape is not waterproof, and this is because the adhesive breaks down when wet which compromises the integrity of any watertight seal. It is however, water resistant, thanks to its material being able to tolerate small amounts of water, but should not be used anywhere that is likely to get excessively wet.

Obviously, live electrical wires should not be exposed to water as this can lead to short circuits and even electrocution so, if PVC electrical tape is water resistant only, what can be used instead?

Alternatives to electrical tape

A great substitute for electrical tape is heat shrink tubing, a thermo plastic tube through which electrical wires are passed. A heat source is applied to the tubing which then shrinks around the wires within it, to create a tight fit over the wires. Adhesive heat shrink tubing has an adhesive lining which, when heated up and applied correctly, will form a waterproof seal. With low conductivity, adhesive heat shrink tubing is an ideal substitute for electrical tape.

Wire connectors can also be used as an alternative to electrical tape at the ends of stripped, exposed wires.

Adhesive heat shrink tubing from cableties-online

Our adhesive heat shrink tubing has a shrink ratio of 3:1, which means it shrinks down to a third of its original size once heat is applied. Please note that as the shrink ratio means that the tubing is three times larger before application than after, this must be taken into account when calculating amounts required.

One final note - other types of tape should never be used as a substitute for electrical tape, due to reduced thermal efficiency which can render them unsafe for use in electrical applications.

If you would like to discuss your electrical tape requirements, our experienced sales team will be happy to answer your queries via email at or by phone on 01623 412160