UKFR - ROOFING AND INSULATION SPECIALISTS

Celotex vs Ecotherm – Which is better?

Ecotherm and Celotex are two of the biggest insulation brands in the UK, both with a wide range of insulation boards to help you reduce your energy bills every year.

Both brands are used and trusted all across the country, but which is better? They offer very similar insulation products, which makes the answer to this less straightforward than other comparisons. So, to answer this, we’ll compare like-for-like boards and focus on their specifications and suitable applications.

Brief Overview

Celotex	Ecotherm
✅ More affordable	❌ Generally more expensive
✅ Good thermal performance	✅ Good thermal efficiency
✅ Suitable for general use	✅ Suitable for general use
❌ Limited resistance	❌ Limited resistance (depending on board)
❌ Not suitable for warm deck flat roofs*	✅ Suitable for warm deck flat roofs
✅ PIR insulation	✅ PIR insulation
✅ Easy to install	✅ Easy to install

Insulated Plasterboard – Celotex PL4000 vs Ecotherm Eco-Liner

There are two options for insulated plasterboard – Celotex PL4000, and Ecotherm Eco-Liner, both of which are made from PIR.

Criteria	Celotex PL4000 (PIR)	EcoTherm Eco-Liner (PIR)
Thermal Performance	0.022 W/mK	0.022 W/mK
Material Composition	PIR	PIR
Moisture Resistance	Good	Good
Durability	Rigid and durable	Rigid and durable
Fire Ratings	Good fire resistance — Euroclass B-s1, d0	Good fire resistance — Euroclass B-s1, d0
Environmental Impact	Contains thermoset plastics; limited recyclability	Similar PIR-based environmental impact; limited recyclability
Costs	Slightly cheaper than Ecotherm	Slightly more expensive than Celotex
Dimensions	1200 x 2400mm	1200 x 2400mm
Thickness	37.5mm – 77.5mm (12.5mm tapered edge plasterboard)	37.5mm – 82.5mm (including 12.5mm tapered edge plasterboard)

Shop Celotex PL4000 →Shop Kingspan K118 →

What is the best insulated plasterboard?

Both boards offer nearly identical specifications, with the only differences being in cost and thickness.

Ecotherm is a slightly more expensive option between the two, so if you’re working with a tight budget, Celotex will be the better option.

Ecotherm does offer slightly thicker boards, so if you require a board thicker than 77.5mm, Ecotherm will be the better option.

Full-Fill Cavity Boards – Celotex Thermaclass 21 vs Ecotherm Eco-Cavity

There are two options for full-fill cavity wall applications: Celotex Thermaclass 21, and Ecotherm Eco-Cavity Full-Fill, both of which are made from PIR.

Criteria	Thermaclass 21	EcoTherm Eco-Cavity Full Fill
Thermal Conductivity (λ-value)	0.021 W/mK	0.022 W/mK
Material Composition	Rigid PIR with low-emissivity foil facings	Rigid PIR with foil facings on both facings
Moisture Resistance	Tongue & groove edges help resist wind-driven rain	Full-fill PIR core with foil facings for moisture protection
Durability	Long-lasting rigid foam	Long-lasting rigid foam
Installation	Lightweight boards with tongue & groove edges for easy fitting	Designed for full-fill cavity walls (up to 10mm residual cavity)
Cost	More budget-friendly	Slightly higher cost
Thickness	90mm – 140mm	90mm – 140mm

Shop Thermaclass 21 →Shop Cavity Wall Insulation →

Which is the best full-fill cavity wall insulation board?

Celotex and Ecotherm offer similar boards for full-fill cavity wall applications, with the only difference being that Celotex has a slightly better thermal performance. Therefore, Celotex Thermaclass 21 will be the better choice as it allows you to achieve target U-values with less insulation.

Partial-fill Cavity Boards – Celotex CW4000 vs EcoTherm EcoCavity Partial Fill

There are two options for partial-fill cavity wall applications: Celotex CW4000, and Ecotherm Eco-Cavity Partial-Fill, both of which are made from PIR

Criteria	CW4000	Eco-Cavity Partial Fill
Thermal Conductivity (λ-value)	0.022 W/mK	0.022 W/mK
Material Composition	Rigid PIR with low-emissivity foil facings	Rigid PIR with foil facings on both facings
Moisture Resistance	PIR core with foil facings for moisture protection	PIR core with foil facings for moisture protection
Durability	Long-lasting rigid foam	Long-lasting rigid foam
Installation	Lightweight, easy-to-install boards designed to fit standard wall tie spacing.	Lightweight, easy-to-install boards designed to fit standard wall tie spacing.
Cost	Slightly cheaper	Slightly more expensive
Thickness	40mm – 100mm	50mm – 100mm

Which is the best partial-fill cavity wall insulation board?

Similar to full-fill insulation boards, both brands offer great boards for partial-fill applications. The only difference between the two is cost and thickness, and in both instances, Celotex comes out on top.

Therefore, if you require a slightly thinner board (40mm), Celotex will be the better option. And if you’re looking for the most cost-effective board, Celotex will again be the better option.

Multipurpose Insulation – Celotex TB, GA & XR vs EcoTherm Eco-Versal

Celotex and EcoTherm both offer a range of multipurpose insulation boards. Celotex offers TB, GA and XR, and Ecotherm has Eco-Versal. The difference between Celotex’s multipurpose insulation is board thickness.

Criteria	Celotex TB, GA, XR	Ecotherm Eco-Versal
Thermal Conductivity	0.022 W/mK	0.022 W/mK
Material Composition	PIR foam core with low emissivity foil facings on both sides	PIR foam core with low emissivity foil facings on both sides
Durability	Good – Not designed for high-compression areas like warm deck flat roofs, however, excellent for use in floors, walls, pitched roofs and cold deck flat roofs	Good – Not designed for high-compression areas like warm deck flat roofs however, excellent for use in floors, walls, pitched roofs and cold deck flat roofs. Ecotherm offers specialist boards for flat roofs: Eco-Fix, Eco-Bond & Eco-Torch.
Cost	Lower	Slightly higher
Application	Celotex TB: Thin board, suitable for reducing thermal bridging. Celotex GA: Walls, floors and roofs Celotex XR: Where thicker insulation is required.	Suitable for floors, walls, roofs, dormer cheeks and ceilings.
Thickness	20mm – 200mm, depending on the board	25mm – 150mm, depending on the board

Shop Celotex TB4000 →Shop Celotex GA4000 →Shop Celotex XR4000 →

Which is the best multipurpose insulation?

Celotex and Ecotherm multipurpose insulation options are virtually identical, offering the same thermal performance, material composition and facings.

The difference between the two lies in affordability and thickness: Celotex is more cost-effective and offers a wider range of thickness, which makes it the clear winner for multipurpose insulation.

However, it’s important to note that if you require boards with higher compressive strength suitable for warm-deck insulation applications, Celotex will not be suitable. In these more-specialist applications, Ecotherm will be the only choice to consider due to their range of flat roof boards (Eco-Fix, Eco-Bond & Eco-Torch).

Celotex vs Ecotherm – Which is cheaper

Money is likely to be the biggest driving factor when it comes to insulation; however, it shouldn’t be the only factor you consider. Whilst upfront costs are essential, you also need to consider the long-term costs and potential energy savings down the line.

Upfront costs – Price per Square Meter

Celotex typically ranges between £15-£30/m².
Ecotherm typically ranges between £15-£30/m².

Long-term costs – Energy Efficiency & Savings

Regardless of whether you choose Celotex or Ecotherm, insulating your home will help you save a lot of money, potentially reducing your energy costs up to 50% saving between £300 to £500 a year.

Celotex vs Ecotherm – which is right for your project?

The choice between Celotex and Ecotherm depends on your budget and the application.

Across standard insulation boards, Celotex is often the more cost-effective option. As both brands offer PIR boards with comparable, and in most cases identical, thermal conductivity ratings, you’ll be able to achieve target U-values while spending less with Celotex.

However, if your project involves a specialist application, particularly flat roofing, EcoTherm is the only choice to consider. This is because they offer a full range of flat roof boards (Eco-Fix, Eco-Bond & Eco-Torch), whereas Celotex do not.

Both brands are easy to install and provide excellent thermal efficiency, helping you create a warmer, more energy-efficient home regardless of which brand you select.

If you need any help with your insulation project, please don’t hesitate to reach out to us today. UKFR is a family-run business, and with extensive knowledge of insulation and flat roofing, we’re here to help you find what you need for your project.

Speak To Us Today →

Celotex vs Ecotherm – Which is better?

Brief Overview

Insulated Plasterboard – Celotex PL4000 vs Ecotherm Eco-Liner

Full-Fill Cavity Boards – Celotex Thermaclass 21 vs Ecotherm Eco-Cavity

Which is the best full-fill cavity wall insulation board?

Partial-fill Cavity Boards – Celotex CW4000 vs EcoTherm EcoCavity Partial Fill

Which is the best partial-fill cavity wall insulation board?

Multipurpose Insulation – Celotex TB, GA & XR vs EcoTherm Eco-Versal

Which is the best multipurpose insulation?

Celotex vs Ecotherm – Which is cheaper

Celotex vs Ecotherm – which is right for your project?

Customer Reviews

Celotex vs Ecotherm – Which is better?

Brief Overview

Insulated Plasterboard – Celotex PL4000 vs Ecotherm Eco-Liner

Full-Fill Cavity Boards – Celotex Thermaclass 21 vs Ecotherm Eco-Cavity

Which is the best full-fill cavity wall insulation board?

Partial-fill Cavity Boards – Celotex CW4000 vs EcoTherm EcoCavity Partial Fill

Which is the best partial-fill cavity wall insulation board?

Multipurpose Insulation – Celotex TB, GA & XR vs EcoTherm Eco-Versal

Which is the best multipurpose insulation?

Celotex vs Ecotherm – Which is cheaper

Celotex vs Ecotherm – which is right for your project?

Customer Reviews

Celotex vs Ecotherm – Which is better?

Brief Overview

Insulated Plasterboard – Celotex PL4000 vs Ecotherm Eco-Liner

Full-Fill Cavity Boards – Celotex Thermaclass 21 vs Ecotherm Eco-Cavity

Which is the best full-fill cavity wall insulation board?

Partial-fill Cavity Boards – Celotex CW4000 vs EcoTherm EcoCavity Partial Fill

Which is the best partial-fill cavity wall insulation board?

Multipurpose Insulation – Celotex TB, GA & XR vs EcoTherm Eco-Versal

Which is the best multipurpose insulation?

Celotex vs Ecotherm – Which is cheaper

Celotex vs Ecotherm – which is right for your project?

Learn More about Celotex & Ecotherm

Celotex vs Kingspan - Which is better?

Recticel vs Celotex

Rockwool vs Celotex

Ecotherm vs Kingspan

Warm Deck Flat Roofing

Customer Reviews

Celotex vs Ecotherm – Which is better?

Brief Overview

Insulated Plasterboard – Celotex PL4000 vs Ecotherm Eco-Liner

Full-Fill Cavity Boards – Celotex Thermaclass 21 vs Ecotherm Eco-Cavity

Which is the best full-fill cavity wall insulation board?

Partial-fill Cavity Boards – Celotex CW4000 vs EcoTherm EcoCavity Partial Fill

Which is the best partial-fill cavity wall insulation board?

Multipurpose Insulation – Celotex TB, GA & XR vs EcoTherm Eco-Versal

Which is the best multipurpose insulation?

Celotex vs Ecotherm – Which is cheaper

Celotex vs Ecotherm – which is right for your project?

Learn More about Celotex & Ecotherm

Celotex vs Kingspan - Which is better?

Recticel vs Celotex

Rockwool vs Celotex

Ecotherm vs Kingspan

Warm Deck Flat Roofing

Customer Reviews