Wall Insulation Board

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In the majority of conventional insulation systems, wall insulation boards are the first line of defence against heat loss. With winter fast approaching and energy bills soaring to record highs, protecting the thermal envelope of your property has never been more crucial. We stock premium phenolic wall insulation as well as partial and full-fill internal and external wall PIR insulation boards to help you make it through the season unscathed.

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What Are Wall Insulation Boards?

The term ‘wall insulation boards’ covers any insulation board that is intended for installation in a wall. Homeowners and contractors alike invest in wall insulation products to reduce the amount of energy they lose through their walls; the average percentage of heat loss through walls alone comes in at a brutal 35%.

As the weather outside gets frightful and we say goodbye to autumn, we also welcome the chances of bitter cold, blinding snowstorms, and howling winds.

By installing wall insulation, you prepare your property for whatever the season brings. By doing so, you can safeguard against heat loss, reducing heating bills and ensuring occupants are kept comfortable all winter long.

We stock insulation boards that are designed for both internal and cavity walls. Our customers can choose from general-purpose, partial-fill, and full-fill boards to meet all of their insulation needs.

Different Types of Wall Insulation Boards

There are two main materials that dominate the wall insulation board market: PIR and phenolic. These materials make for the best wall boards because of their low thermal conductivity values in comparison to other insulants.

Both PIR and phenolic are rigid thermoset foams that function as insulating cores between two facings. The main difference between them is the materials and the manufacturing process.

Both phenolic and PIR foam have combustible properties. However, they do deliver excellent protection against moisture and are ideal for areas with high rainfalls.

PIR, or polyisocyanurate, is a closed-set thermoset polymer; in short, PIR insulation board is a tough, durable, lightweight insulating board comprising two high-performance aluminium facings sandwiched between a rigid PIR insulation core. PIR insulation boards have a thermal conductivity value of 0.022 W/mK.

Kingspan phenolic insulation boards have a marginally lower thermal conductivity value of 0.018 W/mK, making them the go-to choice for people who are looking to make their property more energy efficient. Unaffected by air infiltration, the boards are water-resistant and resist both moisture and water vapour.

General Purpose Internal Wall Insulation Boards

General-purpose boards are designed for installation in internal walls. Celotex and EcoTherm are two of the most popular internal wall insulation board suppliers. Each board is 2400mm by 1200mm.

Celotex creates the best internal wall insulation products for people who want eco-friendly products that do not compromise on thermal performance. Celotex TB4000 boards are BBA-certified thermal insulation solutions purposed to combat thermal-bridging in a variety of floor, wall and roof applications. 

The 2.4m x 1.2m boards are manufactured using a blend of specially designed blowing agents that have zero ozone depletion potential (ODP) and low global warming potential (GWP). Not only do they promise environmental kindness but TB4000 boards also bring in maximum thermal efficiency with thermal conductivity of just 0.022 W/m.K.

They can be installed directly onto a wall. Alternatively, you can build a new stud wall and then attach thermal insulation boards to its interior face.

Cavity Wall Insulation Boards

Masonry walls are comprised of two walls with a space in between. The term 'cavity insulation' refers to insulation that is designed to slot in this designated space between masonry walls.

Given that homeowners lose around 35% of the heat in their homes through uninsulated walls, cavity insulation wall boards are a preventative measure against heat loss and ensure year-round temperature regulation, no matter the forecast.

We offer a comprehensive range of 1200mm by 450mm PIR and phenolic foam external wall insulation boards. From Kingspan Kooltherm K108 partial-fill cavity boards to full-fill cavity wall insulation. 

Full-fill boards are ideal for people who need to install insulation quickly. You can simply slot the boards in place, without having to leave the air gap required in partial-fill walls. The boards are held in place by the masonry walls, meaning you do not need to spend time and money securing them.


Drylining Internal Wall Insulation

Insulation can be applied to the wall surface immediately if there is no damp present and the plaster seems to be in good shape.


Boards can be composed of:

  • rigid foam boards (lightweight insulation sheets come with a waterproof coating to inhibit damp)
  • mineral wool insulation (excellent insulating and soundproofing properties, as well as being moisture-resistant and fire-resistant)


Where acoustic insulation counts, Rockwool 1200mm x 600mm slabs are the best soundproofing insulant on the market. 

Frequently Asked Wall Insulation Board Questions

Frequently Asked Wall Insulation Boards Questions

How to Fit Wall Insulation Boards?

Internal insulation is typically attached to interior walls with screws or bonding and usually extends from the bottom of the ground floor up to eaves level. It then continues and marries with the roof insulation.

External wall insulation involves putting an insulating material layer on the wall and then topping it with a specific sort of render (plasterwork) or cladding. When insulating exterior walls, a common method is to install rigid boards along with a vapour barrier.

Always consult with a professional for detailed guidance.

How to Fit Insulation Board to External Walls?

We discourage homeowners from insulating solid walls themselves. In most cases, homeowners employ professionals to install external solid wall insulation. This type of insulation can also change the outward appearance of your home, which may require planning permission. 

The installation process is complicated and involves lots of different steps. Professionals have to undertake render tests, remove pipework, and protect windows before they can even think about installing external wall insulation. When it comes to high-performance thermal materials, it pays to speak to the experts to ensure the work adheres to current building regulations.

Where To Install Internal Wall Insulation?

Insulating interior walls is an excellent choice for solid wall homes where external insulation isn't feasible or allowed, such as listed structures, conservation areas, or any other situation where you want to maintain the appearance of a property.

At Materials Market, we stock Kingspan K118 Insulated Plasterboard - one of the thinnest available Internal Wall Insulation (IWI) - solutions. These plasterboards are ideal for use in buildings that can’t be insulated on the outside.

Internal wall insulation should be considered in the following applications:

  • External walls that are insufficiently insulated
  • External walls that are either in a state of disrepair or do not provide sufficient defence against the weather, resulting in dampness, draughts and heat loss
  • Applications where external insulation would adversely affect building appearance
  • Retrofit projects and existing buildings


Benefits of Exterior Wall Insulation

  • Unlike internal insulation, it can be installed with minimal disruption
  • It won't encroach on a building's floor space - you don't want to lose valuable floor space by insulating internally 
  • Can be used to improve the aesthetic of your external walls - offering an improved and cleaner façade to the exterior of your home.
  • Protects the fabric of your property's brickwork, increasing its overall lifespan
  • Improves energy efficiency, reducing heating costs and carbon footprint


Where Can I Shop Online for Wall Insulation Boards?

You can buy insulation wall boards directly from our online shop. We have one of the widest ranges of general-purpose boards in the UK. You can buy general-purpose internal wall insulation boards from the EcoTherm Eco-Versal range. Kingspan Kooltherm K108 is ideal for cavity wall insulation and is available in a range of thicknesses from 50mm to 100mm.

Our online shop is an easier, quicker alternative to brick and mortar construction supply shops. We can deliver internal wall insulation and external boards straight to your home or commercial construction site.

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