Polystyrene Backed Plasterboard

EPS insulated plasterboards are 2-in-1 products. They are comprised of extruded polystyrene insulation (EPS) and a 9.5mm tapered edge plasterboard. Polystyrene insulated plasterboard is designed for installation on the internal side of blockwork walls to provide thermal insualtion. It is ideal for people who favour easy installation over thermal conductivity. The polystyrene insulated plasterboards in our range have a thermal conductivity of 0.038 W/mK, and come in thicknesses of 22mm, 30mm and 40mm.


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What Is Polystyrene Backed Plasterboard?

Plasterboard polystyrene insulation is sometimes called thermaline basic or even jablite plasterboard (after the popular manufacturer of EPS insulation). The term “basic” comes from the fact that these insulated plasterboards are the least thermally efficient out of phenolic, PIR and EPS insulated plasterboard, and offer a basic level thermal performance. As such, they should only be used where thermal values do not need to be lower than 0.038 W/mK.

These 2400mm by 1200mm boards offer an all-in-one solution to people who want to save time and money. Each board is comprised of a sheet of thermal insulation that is bonded to a 9.5mm tapered edge plasterboard. The plasterboard only covers one side of the insulation.

These boards are designed for installation on the internal side of blockwork walls. Drylining and insulation are built into the one product, which means that you can save time and money on installation. You never have to worry about poor construction practices when you choose pre-bonded thermaline basic insulated plasterboards. Each board is made to the same high standards, meaning you will always get a clean finish.

EPS Plasterboard

EPS insulated plasterboards contain a sheet of expanded polystyrene insulation (EPS). EPS is made from hydrocarbon compounds. Styrene creates the cellular structure of the material, and pentane acts as the blowing agent. EPS forms when small polystyrene foam beads are heated in a mould. The beads expand and fuse, but not all the beads touch. EPS does not have a closed-cell structure, meaning it is not a good thermal conductor.

The finished product is very lightweight. There are lots of pockets of air inside EPS sheets. Air is a poor conductor of heat, which is why EPS plasterboards have a relatively low thermal conductivity value. They have a thermal conductivity of 0.038 W/mK. Other insulation materials such as PIR have a much lower – and therefore better –  thermal value but are much more expensive.

Polystyrene Backed Plasterboard Thickness

We stock thermaline basic insulated plasterboard in different thicknesses. You can choose from 22mm, 30mm, and 40mm thicknesses. You can either install jablite plasterboards alone or as part of a build-up of other insulation materials. The thickness you choose will be determined by how much space you have available, and the required U-Value of the buildup.

Frequently Asked Polystyrene Backed Plasterboard Questions

Benefits of EPS Insulated Plasterboards?

●     All-in-one product – One of the biggest benefits of polystyrene plasterboards is that they save time. Each board is comprised of insulation and plasterboard drylining. You can simply install the board on the internal side of a blockwork wall. When you choose all-in-one boards, you do not have to spend time sourcing different materials and fitting them together.

●     Tapered edge – Each EPS insulated plasterboard in our range has a tapered edge. Boards that have tapered edges are best suited to walls that have a narrower edge profile. The tapered finish allows installers to achieve a seamless finish between sheets. We recommend these boards for people who want to create sturdy structures that will retain their effectiveness for years to come.

●     Thermal Performance – EPS has a thermal insulation conductivity value of 0.038 W/mK. It is often not the first choice for people who want to improve the thermal envelope of their homes, but it is far cheaper than more effective alternatives such as PIR insulation. EPS plasterboards are also very easy to handle and install.

●     Moisture-resistant – You do not have to worry about drylining when you invest in 2-in-1 plasterboards. There is a 9.5mm tapered edge gypsum plasterboard attached to each sheet of EPS insulation. It functions as a barrier against moisture. Moisture can lead to rot, which can threaten the longevity and effectiveness of your insulation.

Do Thermaline Basic Plasterboards Reduce Noise?

The sound-deadening qualities of EPS plasterboards are often overlooked. EPS is marketed as insulation that reduces heat loss and improves the thermal envelope of domestic and commercial spaces. This material contains thousands of pockets of air, which means that it also acts as a barrier for sound vibrations. When sound waves enter a material, they become sound vibrations. Sound vibrations dissipate when they hit pockets of still air.

Jablite plasterboards can reduce the volume of unwanted noise in your home. Lots of people install all-in-one plasterboards on the internal walls in their bedrooms and home offices.

Where Can I Install Polystyrene Plasterboards? 

Polystyrene backed plasterboards are designed for installation on the internal side of blockwork walls. They contain in-built tapered edge plasterboard on one side. Each board is built in accordance with industry standards. They are approved for use in both refurbishment and new build insulation projects.

How to Cut Insulated Polystyrene Plasterboards?

We stock 2400mm by 1200mm thermaline basic insulated boards. This standard size suits most insulation projects. In some situations, you might need to cut your insulated plasterboards down to size.

Cutting 2-in-1 plasterboard is easier than you might think. The plasterboard is the most rigid part of the product. You can cut through both the plasterboard and the insulation with a handheld saw, or even a very sharp knife. We encourage our customers to avoid Stanley knives, as they can become blunt very quickly.

Follow these steps for a clean, concise cut.

  1. Wear protective gear such as goggles and gloves.
  2. Use a ruler to mark the line that you want to cut. Run a knife down the line to create a guide for your saw.
  3. Use your saw to cut through the line. Make sure that your saw cuts through the plasterboard.

How to Install Plasterboard Polystyrene Insulation?

We recommend using mechanical fixings and/or the dot and dab technique to install EPS insulated plasterboards. Lots of people use both fixings and adhesive for extra security, but you can achieve the same result with one or the other.

The dot and dab technique is an alternative to the traditional wet plaster method. The wet plaster method involves covering the entire internal wall with plaster. It takes hours to dry, which is an unnecessary expense for people who are paying labourers by the hour. The dot and dab technique uses less adhesive and saves more time.