INSULATED PLASTERBOARD

Insulated plasterboard also called 'thermal' is a modern version of wallboard bonded to insulation core such as polystyrene EPS, Phenolic foam, or extruded XPS which is the best cost-effective solution to insulate your walls and ceiling without adding too much depth. They are also useful in roofs when it comes to flat roof windows or pitched roof windows. Thermal plasterboard is available in a variety of sizes and thicknesses ranging from 22mm, 25mm, 30mm up to 112.5mm. It can be fixed with plasterboard fixings known as a plasterboard screws or plasterboard wall plugs or even Knauf or British Gypsum plasterboard adhesive. The ability to install Insulation Plasterboard quickly as its a two in one solution is a huge advantage. It can also be plastered with MultiFinish plaster. Thermal wallboard goes by many names and is well known from Google search engine as Wickes or Kingspan insulated plasterboard. However, it can be quickly easily located near your postcode by driving down to the nearest B&Q or Screwfix store. Most common insulated plasterboard thicknesses are 25mm (24.5mm) and 50mm (49.5mm). For more information on how to install insulated plasterboard click here.

TYPES OF INSULATED PLASTERBOARD

When it comes to application you can choose from standard insulated plasterboard commonly used on walls and ceilings and moisture resistant insulated plasterboard for wet rooms, bathrooms and shower rooms. 

STANDARD INSULATED PLASTERBOARD

A standard insulated plasterboard comprises standard Drywall Plasterboard pre-bonded to thermal insulation core.

MOISTURE RESISTANT PLASTERBOARD

Moisture resistant insulated plasterboard is backed with rigid polyisocyanurate foam insulation and two vapour barriers which are specially designed to use in wall lining and internal wall partitions. These boards are mostly used where both high thermal performance and high moisture resistance is required.

When it comes to thermal plasterboard performance you can choose from Phenolic, EPS (Expanded PolyStyrene), XPS (EXtruded PolyStyrene) and PIR (PolyIsocyanuRate) insulation core.

PHENOLIC FOAM PLASTERBOARD

Phenolic plasterboard is a premium performance insulation with a fibre-free rigid thermoset phenolic core. It provides a level of performance that is unrivalled in the world of rigid thermoset insulation materials with a thermal conductivity of just 0.018 W/mK across all thicknesses. It is a top-class three-in-one product for internal wall insulation used as mechanically fixed and adhesively bonded 'dot and dab' insulated plasterboard. For example, Kingspan K118 range is a high-efficiency phenolic insulation core with a certified thermal conductivity (lambda value) of 0.018W/mK factory bonded to 12.5mm premium plasterboard. Kooltherm K118 (previously Kingspan K18 and K17) provides high-levels of insulation, dry-lining and vapour control layer in one easily applicable 2400mm x 1200mm (8x4) insulating sheets.

PIR INSULATED PLASTERBOARD

Pir core wall panel is an insulated plasterboard combined of polyisocyanurate (PIR) rigid insulation foam core bonded to 9.5mm or 12.5mm tapered edge plasterboard that is suitable for internal applications, fixed with adhesive dot and dab direct bonding.

EXPANDED POLYSTYRENE EPS INSULATED PLASTERBOARD

EPS Insulated Plasterboard is a cost-effective way of improving thermal efficiency in both wall and roof applications. Made from expanded polystyrene foam insulation bonded to 12.5mm thick plasterboard, this insulation solution can be used for both new build and refurbishment projects.

EXTRUDED POLYSTYRENE XPS INSULATED PLASTERBOARD

XPS Laminates are fabricated by bonding a sheet of XPS insulation, a close-celled extruded polystyrene board made from melting plastic resins that are then extruded through a die and expanded during the cooling process, to tapered edge plasterboard.

INSULATED PLASTERBOARD MANUFACTURERS ǀ THICKNESSES

Insulated plasterboards are produced by well known brands such as Kingspan, Celotex, Xtratherm, British Gypsum, Warmline and Knauf. All of the brands offer a variety of products and thicknesses. Moreover, boards are available either in standard or moisture resistant versions. The thickness of insulated plasterboard used will depend on the build-up of the wall and u-value which is being targeted.

PHENOLIC CORE

Kingspan Kooltherm K118 - 32.5mm, 37.5mm, 42.5mm, 52.5mm, 57.5mm, 62.5mm, 72.5mm, 82.5mm, 92.5mm.

Xtratherm SR/TB Safe - R Thermal Liner - 37.5mm, 52.5mm, 62.5mm, 72.5mm, 87.5mm, 92.5mm, 112.5mm.

PIR CORE

Xtratherm XT/TL Thermal Liner - 24.5mm, 27.5mm, 29.5mm, 32.5mm, 34.5mm, 37.5mm, 39.5mm, 42.5mm, 44.5mm, 47.5mm, 49.5mm, 52.5mm, 54.5mm, 57.5mm, 59.5mm, 62.5mm, 64.5mm, 67.5mm, 69.5mm, 72.5mm, 74.5mm, 77.5mm, 79.5mm, 82.5mm, 84.5mm, 87.5mm, 92.5mm, 99.5mm, 102.5mm, 109.5mm, 112.5mm, 119.5mm, 122.5mm.

Celotex PL4000 PIR Thermal Insulated Plasterboard - 27.5mm, 32.5mm, 37.5mm, 42.5mm, 47.5mm, 52.5mm, 57.5mm, 62.5mm, 67.5mm, 72.5mm, 77.5mm.

British Gypsum Gyproc Thermaline PIR Insulated Plasterboard - 38mm, 53mm, 63mm, 78mm, 93mm.

Knauf PIR Laminate - 35mm, 50mm, 65mm, 75mm.

Ecotherm Eco-Liner - 37.5mm, 42.5mm, 52.5mm, 62.5mm, 72.5mm, 82.5mm.

Speedline PIR Thermal Laminate Board - 37.5mm, 62.5mm, 72.5mm.

Warmline PIR Insulated Plasterboard - 27mm, 29mm, 35mm, 38mm, 48mm, 50mm, 60mm, 62.5mm, 70mm, 72.5mm, 80mm, 82.5mm, 90mm, 92.5mm, 102mm.

XPS CORE

Warmline XPS Insulated Plasterboard - 27mm, 35mm, 40mm, 45mm, 55mm.
Knauf XPS Laminate Plus - 27mm, 35mm, 40mm, 45mm, 55mm.

EPS CORE

Knauf EPS Thermal Laminate Insulation Board - 22mm, 30mm, 40mm, 50mm.
Gyproc Thermaline Basic Insulated Plasterboard - 22mm, 30mm, 40mm.

INSULATED PLASTERBOARD BUILDING REGULATIONS

Building Regulations are law and must be met when applied to any project over a certain size. Where 50 percent or more of the internal wall is being renovated building regulations would normally apply, and the thermal insulation of the wall would have to meet the standards required by building regulations approved documents. The regulation that refers to the thermal efficiency requirements when carrying out renovation or replacement work on an existing dwelling is explained in Approved Document L1B (ADL1B). For instance, to meet Part L when constructing an extension you need to meet a U-value of 0.28W/m2K. When new layers are added to a thermal element through being dry lined internally the U-value of 0.30W/m2K is required. If at least 50% of the element is being renovated then it should be upgraded to achieve the U-values as follow:

Pitched roof - insulation at ceiling level 0.16W/m2K.
Flat roof or roof with integral insulation 0.18W/m2K.
Pitched roof - insulation between rafters 0.18W/m2K.

Insulated plasterboard is not suitable for use on such walls where there is a risk of moisture penetration or on timber or steel frame construction. This method is only suitable for use on brick, blocks, concrete cavity or rendered solid walls which are dry, stable and most importantly free from moisture penetration. Where you don't have cavities in your wall you shouldn't adhesively bond because of the risk of moisture penetration from outside. In this particular situation you should always mechanically fix wooden battens and screw the plasterboard to battens.

INSULATED PLASTERBOARD PRICE

Because thermal plasterboard can be used in so many different situations, it is important to know you’re getting the best price, particularly if you’re working within a tight budget. If you are looking for the plaster-boarding cost per m2 you should be looking for £9.05 per m2 and £26.09 per sheet. This is based on British Gypsum Gyproc ThermaLine Basic insulated plasterboard. Here at InsulationGo we offer other top brands such as Kingspan, Xtratherm, Knauf and Warmline. We usually keep in stock our most favourite Kingspan K118 in 50mm thickness. 

In terms of performance all types of insulated plasterboards are classified in given order (based on 52.5mm thickness): 

1. Phenolic insulated plasterboard / Thermal Conductivity: 0.018 W/mK
2. PIR insulated plasterboard / Thermal Conductivity: 0.022 W/mk
3. XPS insulated plasterboard / Thermal Conductivity: 0.030 W/mk
4. EPS insulated plasterboard / Thermal Conductivity: 0.034 W/mk

In terms of prices, the insulated plasterboard list looks completely different (based on 32.5mm thickness). 

1. EPS insulated plasterboard / £38.03
2. XPS insulated plasterboard / £48.60
3. PIR insulated plasterboard / £57.08
4. Phenolic insulated plasterboard / £69.21

The cheapest product would be EPS bonded to plasterboard such as Warmline EPS Insulated Plasterboard, British Gypsum Gyproc Thermaline Basic or Knauf EPS Thermal Laminate. On the other hand, the most expensive insulated plasterboard would be phenolic insulated plasterboard such as Kingspan Kooltherm K118 or Xtratherm XT/TL Thermal Liner. Those boards are the most effective type of rigid phenolic insulation boards currently available in the UK.

Video credit:https://www.youtube.com/watch?v=fHX0QOV4e8U

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