Tile Backer Board vs Plasterboard: Which Should You Use?

If you’re preparing to tile a bathroom, kitchen, or splashback, your choice of surface matters more than you think. Use the wrong substrate and you risk water damage, tile movement, or complete adhesive failure.

One of the most common questions we hear:
Should I use plasterboard or a tile backer board?

This guide breaks down the key differences and helps you choose the best option for your project.

TL;DR – Quick Comparison Table

What Is Plasterboard?

Plasterboard (aka drywall or gypsum board) is made from a gypsum core between two sheets of paper. It’s widely used for wall and ceiling construction in the UK and is often already installed in many homes.

While it’s cheap and easy to work with, it’s not designed for direct tiling in wet environments.

You can tile onto moisture-resistant (green) plasterboard, but it needs priming and careful prep. Even then, it won’t survive long-term water exposure.

What Is a Tile Backer Board?

Tile backer boards are purpose-made boards designed to go behind tiles. They're built to stay rigid, waterproof, and stable even in the most demanding wet environments.

Beava Backer Boards are made from high-density foam with a cementitious coating. This gives them a perfect tiling surface, plus additional thermal insulation.

They come in two main sizes:

• Beava Backer Board 6 mm – ideal for walls or overboarding stable timber floors

• Beava Backer Board 12 mm – perfect for wet rooms, uneven substrates, or load-bearing areas

Key Differences You Need to Know

1. Water Resistance

• Plasterboard: Absorbs water like a sponge.

• Backer Board: 100% waterproof. Ideal for wet rooms, showers, and behind baths.

Backer boards protect your tiles and prevent long-term moisture problems like mould and rot.

2. Tile Adhesion and Stability

• Plasterboard: Soft surface and can degrade over time.

• Backer Board: Strong, rigid, and holds adhesive like a pro.

This means fewer popped tiles and better long-term hold.

3. Thermal & Acoustic Insulation

Beava backer boards also offer better thermal resistance, which is perfect when used with underfloor heating systems.
They also help with soundproofing, particularly in bathrooms.

4. Durability and Lifespan

Backer boards are engineered to last as long as the tiles themselves. Once tiled, they won’t sag, warp or fail - unlike plasterboard in humid conditions.

5. Cost Comparison

Plasterboard is cheaper per sheet, but consider the extras:

• Primers

• Waterproofing

• Risk of failure

Backer boards are a one-and-done solution. They save time, reduce prep, and last longer.

When Is Plasterboard Acceptable?

You can tile onto moisture-resistant plasterboard if:

• It’s in a dry zone (e.g. above a sink splashback)

• You prime it properly

• The area isn’t exposed to regular steam or water spray

However, we don’t recommend plasterboard in bathrooms or wet rooms. Ever.

Final Verdict: Choose Beava Backer Boards for Peace of Mind

If you're tiling a bathroom, wet room, or kitchen splashback — go with a backer board. It’s a safer, longer-lasting, and more professional solution.

Beava Backer Boards are lightweight, waterproof, and built for purpose.
They're available in 6mm and 12mm, with fast UK delivery and trusted reviews.