Your Guide to Insulated Plasterboard

What is Insulated Plasterboard?

The UK has a reputation for having cold, wet, and windy weather — and sometimes, brick and stone walls just aren’t enough to keep the cold out of your house. With that comes the need for a reliable layer of insulation to keep you warm and comfortable indoors.

Insulated plasterboard is a cost-effective and convenient building material suitable for UK properties. It offers optimal thermal insulation and a smooth finish for your walls in a single application, saving you time and money.

In this in-depth guide, we’ll discuss everything you need to know about this dual-purpose material, including standard sizes, types, uses, and benefits. We’ll also help you decide whether insulated plasterboard is the right choice for your home.

What Is Insulated Plasterboard?

Insulated plasterboard, also known as thermal plasterboard, is a construction material that combines a sheet of traditional plasterboard or gypsum board with a layer of insulation.

It’s commonly used for internal walls, but it can also cover floors, ceilings, and external walls.

This material can be installed over bricks, blocks, concrete, stone, and timber frames and is suitable for new builds, refurbishments, and both commercial and domestic projects. 

In a typical British home, around 35% of heat is lost through inadequate wall insulation. Installing insulated plasterboard is one way to improve your home’s energy efficiency and reduce your heating bills.

Common Sizes and Types of Insulated Plasterboard

Insulated plasterboards come in a wide variety of sizes and thicknesses, but they’re typically 2.4m long and 1.2m in width, with an overall thickness ranging from 22mm to 102mm.

Smaller board sizes, such as 1.2m x 1.2m and 1.2m x 0.45m plasterboards, are also available, but larger board sizes are preferable because they cover a lot of wall area more easily and quickly.

Special features, such as tapered edges, also make it more convenient to position and install a lot of boards in a short amount of time.

Insulated plasterboards also vary in terms of materials used for insulation. Some of the most common types are PIR-insulated plasterboard, Phenolic-insulated plasterboard, and EPS-insulated plasterboard.

In addition to basic insulated plasterboards, there are fire-resistant, vapour-controlled, moisture-resistant, eco-liner, tapered edge, and square edge varieties of plasterboards as well.

Some well-known manufacturers of insulated plasterboards in the UK include Celotex, Ecotherm, Gyproc, Kingspan, Siniat, and Warm Line.

Standard vs. Insulated Plasterboard

Standard plasterboards are often used in combination with a separate insulating material like rock wool, sheep’s wool, or glass wool, whereas insulated plasterboards are a two-in-one solution where the plasterboard and insulation are already bonded together.

Because of the complex and lengthy installation, you might need an insulation expert to properly attach the individual layers of standard plasterboard and insulation material in your home. 

Meanwhile, insulated plasterboards can be installed quickly using only an adhesive, making it the easier and faster alternative between the two. 

Insulated plasterboards are specifically designed to provide thermal resistance, which stops heat from leaving the walls of your home. Although it can cost more than standard plasterboards, the savings on energy bills will make it a cheaper alternative in the long run.

One thing to note is that insulated plasterboard can be more challenging to cut into your preferred size because of the layer of insulation attached to the back. The best way to do so is with a sharp knife or saw that can cut all the way through the insulation and the paper backing. 

Benefits of Using Insulated Plasterboard

There are countless options to choose from when insulating homes and buildings in the UK. 

But if you’re looking for a dual-purpose product with the structural integrity of plasterboard and the warmth and comfort of insulation, insulated plasterboard offers the best of both worlds.

Here are a few reasons why this popular building material is worth considering:

1. Thermal Efficiency

The major appeal of insulated plasterboard is that it keeps your home cooler in the summer and warmer in the winter, making it more comfortable for everyone inside.

You’ll rely less on fuel or electricity for your heating and cooling needs, which means your home’s energy efficiency will go up and your utility bills will go down. It’s a win-win situation for you, your wallet, and the environment.

2. Saves Time, Space, and Money

Insulated plasterboard is a two-in-one solution that simplifies the process of using separate standard plasterboard and insulation materials. No need to spend extra time and money on buying and installing two different parts of your wall!

The short installation time not only reduces your hourly labour costs but also allows you to start decorating your wall sooner. Plus, insulated plasterboard has a thin profile and won’t significantly affect your wall thickness, ideal for adding insulation to rooms with limited space.

3. Easy to Install

You won’t need a lot of professional machinery or expertise to install an insulated plasterboard. Removing the material from your walls is simple and straightforward as well.

If you use the “dot and dab” technique, you’ll only be working with basic tools like a saw, knife, hawk, trowel, bucket, and tape measure, along with construction adhesive and insulated plasterboards. It’s a hassle-free alternative to applying wet plaster.

4. Low Maintenance

With insulated plasterboards, you can basically “install it and forget it.” These boards are tough, resilient, rot-proof, and maintenance-free. 

They’ll keep your home comfy and well-insulated for many years without the need for costly repairs or replacements.

5. Environmentally Friendly

Insulated plasterboard effectively maintains a stable and habitable temperature indoors, reducing the need to use electricity, natural gas, or fuel to heat up or cool down the house.

As a result, your home decreases its carbon footprint and emits fewer air pollutants like carbon dioxide, nitrogen oxide, and sulphur oxide, among others. You’ll get cleaner and healthier air in and out of your house!

6. Soundproofing Properties

Choosing a thick variety of insulated plasterboard with enhanced acoustic properties can help with noise reduction for your home. 

It minimises the transmission of sounds, such as voices, footsteps, appliance hums, and floor creaking, between rooms. It’s especially useful in shared living spaces, like apartment buildings and condominiums.

7. Fire and Moisture Resistant

Fire-resistant insulated plasterboards are specifically designed for fire protection. This type of plasterboard uses materials like fibreglass, which can withstand high temperatures and prevent fire from spreading fast. It’s best for cooking spaces, fireplaces, and high-heat areas at home.

Moisture-resistant plasterboards with built-in vapour barriers are also available. They’re great for wet areas, like kitchens and bathrooms, where standard plasterboard might not be advisable.

How to Install Insulated Plasterboard

Correctly installing your insulated plasterboard is a vital step in ensuring that your home is as energy-efficient, eco-friendly, and comfortable as possible. 

Improper installation can allow heat to leak out of your house during the winter or penetrate your home in the summer. It can also result in air gaps, damp problems, and condensation. All these issues can drive up your utility bills and affect the air quality inside your home.

There are two common methods of installing insulated plasterboard. The dot and dab technique uses construction adhesive, while mechanical fixing requires plugs, drywall screws, hammerfix screws, or masonry nails. 

Dot and Dab Technique

This method is best for dry and structurally sound cavity walls made of bricks, blocks, and concrete. As its name implies, you will dot and dab adhesive directly onto your wall before pushing the plasterboard in place.

It’s a fast, effective, easy, and long-lasting method for installing insulated plasterboard. However, it’s not fit for use on timber or steel frame construction or walls with a risk of moisture penetration. Here are the basic steps for this technique:

1. Prepare the wall surface by removing oil, grease, wallpaper, dust, or any substance that may affect the bonding of the adhesive to the wall.

2. Mark the position of each plasterboard on the wall, floor, and ceiling to know where you’ll apply the adhesive. Start from an internal corner, window, or door.

3. On a flat surface, cut your plasterboards to the correct size using a tape measure and a fine-toothed saw or utility knife.

4. Carefully follow the manufacturer’s instructions when mixing your adhesive in a bucket.

5. Apply a continuous solid line of adhesive around the perimeter of your wall and around openings using a hawk and trowel. Then, dot and dab adhesive on the wall every 20 to 30 cm. The dabs should be big enough to support your plasterboards.

6. Press your plasterboards into position and check their alignment using a spirit level.

7. To add more support, you can apply two to four mechanical fixings per board after the adhesive has been set.

Mechanical Fixing

Using plasterboard fixings, such as nails, screws, and plugs, will ensure greater stability and performance. It’s necessary for ceilings, surfaces where an adhesive bond isn’t suitable, and walls where you plan on attaching heavy surface linings, like tiles. 

Mechanical fixing can involve fixing wooden battens to your walls and screwing your plasterboard onto the battens. It’s sturdy but more expensive and time-consuming than the dot-and-dab method and takes up a larger amount of space for each interior wall.

You can also screw the plasterboard directly into wall plugs that are embedded in your masonry walls. However, this option isn’t advisable due to the risk of thermal bridging from using conductive materials. These materials can cause higher levels of heat to pass through the walls.

Whichever method you choose, ensure that you wear protective equipment while working. These include gloves, a dust mask, eye protection, and appropriate clothing.

Enjoy the Benefits of Insulated Plasterboard in Your Home

So, is insulated plasterboard a worthwhile option for your wall, floor, or ceiling? 

Since it combines the functions of plasterboard and insulation in one convenient product, insulated plasterboard can be a great choice for homes that need a time-saving, cost-effective, and energy-efficient heating solution.

However, the decision ultimately depends on your specific needs, your home’s existing conditions, and local building regulations in your area

If you’re looking for expert advice and a qualified installer to add insulated plasterboard to your walls, Insulation Advisor has precisely what you need! You can get started today with a free insulation quote.

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