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Kingspan K18 Mechanically Fixed Insulated Plasterboard

High performance Kingspan product, available in most popular thickness’s from the manufacturer, therefore short lead-times apply. This Kooltherm Range includes the following readily available product thickness's 20mm, 25mm, 30mm, 40mm, 50mm and 60mm. Manufactured to order are the following thickness's 70mm, 80mm, 100mm and 120mm

Product Functions

Kingspan K18 / Kooltherm K18 Insulated Wallboards Dry Wall Phenolic Thermal Laminates for Mechanical Fixing

Combining insulation, dry-lining and vapour control in one board, Kooltherm K18 is ideal for use in timber frame constructions or on any dry masonry walls that can support and retain the battens/furrings and associated fixings.

Used when fixing to solid wall constructions that are susceptible to moisture penetration.

Product Description

The Front Facings

The front facing of K18 Insulated Plaster Board is a tapered edge gypsum based plasterboard which readily accepts dry–jointing materials, plaster skim or direct decoration.

The Reverse Face

Kingspan K18 Kooltherm K18 phenolic foam laminated to plasterboard offer highest thermal performance in this board for mechanical fixing

The reverse facing of K18 Insulated wallboard is a Composite foil facing autohesively bonded to the insulation core during manufacture.

The Core

The core of K18 Insulated Wallboard is a premium performance CFC/HCFC free rigid thermoset phenolic insulant of typical density 35 kg/m3.


K18 Insulated Dry-lining Board is manufactured without the use of CFCs/HCFCs and has zero Ozone Depletion Potential (ODP).

Compressive Strength

Typically exceeds 100 kPa at 10% compression when tested to BS EN 826: 1996 (Thermal insulating products for building applications. Determination of compression behaviour).

Water Vapour Resistance

Modified to include board facings, the boards achieve a resistance far greater than 100 MN.s/g, when tested in accordance with BS 4370–2: 1993 (Methods of test for rigid cellular materials. Methods 7 to 9)
Where additional vapour control is required an appropriate surface treatment should be applied over the completed insulated wall area (see ‘Water Vapour Control’)


K18 Insulated Dry–lining Board has a gypsum plasterboard face. It should, therefore, not be used to isolate dampness nor be used in continuously damp or humid conditions.


If correctly applied, K18 Insulated Wall Board has an indefinite life. Its durability depends on the supporting structure and the conditions of its use.

Resistance to Solvents, Fungi & Rodents

The insulation core is resistant to short–term contact with petrol and with most dilute acids, alkalis and mineral oils.
However, it is recommended that any spills be cleaned off fully before the boards are installed. Ensure that safe methods of cleaning are used, as recommended by the suppliers of the spilt liquid.
The insulation core is not resistant to some solvent–based adhesive systems, particularly those containing methyl ethyl ketone. Adhesives containing such solvents should not be used in association with this product.
Damaged boards or boards that have been in contact with harsh solvents or acids should not be used.
The insulation core and facings used in the manufacture of K18 Insulated Plaster Board resist attack by mould and microbial growth and do not provide any food value to vermin.

Product Benefits

    Premium performance rigid phenolic insulation thermal conductivity as low as 0.021 W/m.K
    Suitable for use in rainscreen cladding systems
    Clear cavity is maintained resists moisture penetration
    Unaffected by air movement
    Resistant to the passage of water vapour
    Easy to handle and install
    Ideal for new build and refurbishment
    Non deleterious material
    CFC/HCFC free with zero Ozone Depletion Potential (ODP)

Product availability indicators

K18 - Price and Availability Advisory:

Presently there are no availability restrictions, apart from manufacturing lead-times and minimum quantity order levels on the 70mm, 80mm, 100mm and 120mm boards

Excellent = Product Availability Excellent Good = Product Availability Good Fair = Product Availability Fair Poor =  Product Availability Poor Undetermined = Product Availability Undetermined
Availability relies on stock levels at closest depots and upon transport logistics to effect deliveries

Technical Data

Kingspan K18 Phenolic Thermal Laminate Insulated Plasterboards

Product Code

Board dimensions

Thickness (mm)

λ Value (w/mK)

R-value (m²K/W)

U Value (W/m²K)

Weight (kg/m²)

Unit weight (kg)

Kingspan K18 32.5mm 24 x 1.2m x 2.4m = 69.12m² 20 0.023 0.90 1.12 9.17 633.84
Kingspan K18 37.5mm 21 x 1.2m x 2.4m = 60.48m² 25 0.021 1.25 0.80 9.35 565.53
Kingspan K18 42.5mm 18 x 1.2m x 2.4m = 51.84m² 30 0.021 1.45 0.69 9.52 493.56
Kingspan K18 52.5mm 15 x 1.2m x 2.4m = 43.2m² 40 0.021 1.95 0.52 9.87 426.45
Kingspan K18 62.5mm 12 x 1.2m x 2.4m = 34.56m² 50 0.020 2.55 0.40 10.22 353.28
Kingspan K18 72.5mm 11 x 1.2m x 2.4m = 31.68m² 60 0.020 3.05 0.33 10.57 334.95
Kingspan K18 82.5mm 9 x 1.2m x 2.4m = 25.92m² 70 0.020 3.55 0.29 10.92 283.05
Kingspan K18 92.5mm 8 x 1.2m x 2.4m = 23.04m² 80 0.020 4.05 0.25 11.27 259.68
Kingspan K18 112.5mm 7 x 1.2m x 2.4m = 20.16m² 100 0.020 5.05 0.20 11.97 241.36
Kingspan K18 132.5mm 6 x 1.2m x 2.4m = 17.28m² 120 0.020 6.05 0.17 12.67 218.94
Thermal conductivity / Lambda value (W/mK) = 0.023 to 0.020 plus 0.190 | Compressive Strength (kPa) = > 100 | Water vapour resistance (MNs/g) = > 100 | Fire Performance = Class 0 | Please Note: R-Value = Thermal Resistance; U-Value = Thermal Transmittance Co-efficient; Compressive Strength = kiloPascals; Vapour resistance = MegaNewton second gram

Product Information and Certification

Links to manufacturer's information. Click to download in a separate browser window.

Kingspan K118 Datasheet

Kingspan Kooltherm® K18 Range - Certification

K18 Wall Framing Board insulation is manufactured to the highest standards under a management system certified to BS / I.S. EN ISO 9001: 2008 (Quality management systems. Requirements), BS / I.S. EN ISO 14001 : 2004 (Environmental Management Systems. Requirements) and BS / I.S. OHSAS 18001: 2007 (Health and Safety Management Systems. Requirements).

CE Marking - Kingspan has provided Decelerations of Performance for its products. CE marking is the visible sign, that the product has met the requirements of the European Norms (ENs) and is therefore compliant with the Construction Products Regulation (CPR).

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Product Installation - Kingspan K18

Fixing the Dry Lining Boards

Depending on the specified fixing method; traditional plaster dab bonding, proprietary adhesive bonding, nailing / screwing to vertical timber framing or battens, screwing to adhesive bonded metal furring systems, nailing / screwing to timber joists or rafters or mechanical fixing directly to masonry substrates, fixing should proceed as follows:–


The ceiling lining should be in position before wall lining commences. Wall mounted fittings such as electrical sockets should be fitted so as to take into account the additional wall thickness.
Heavy surface mounted fittings will require provision for the fixing load to be applied direct to the supporting wall and not to the K18 Insulated Wallboard in isolation. On existing constructions all surfaces should be clean and free of loose or flaking materials. Wallpaper should be stripped and surface mounted fittings removed.

Window / Door Reveals and SoffitsKingspan K18 Insulated plasterboard in wooden stud wall application

Narrow widths of board should be cut and rebated to allow a plasterboard / plasterboard joint at the angle. Fixing should employ the same method as is used for the plain wall areas.
Care should be taken to ensure that the cavity in cavity wall constructions is not bridged by the board or fixing medium in such a manner that would allow the passage of water through to the inner leaf. Where adhesives are employed, soffit boards and boards at window heads should be temporarily supported.

Mechanical Fixing to Vertical Timber Framing / Battens

This method may be used on timber frame constructions or on any dry masonry walls that will support and retain the battens and associated fixings. K18 Insulated Wallboard should be fixed to timber framing / battens set at maximum 600 mm centres and positioned horizontally at floor and ceiling level. The timbers should run vertically and be wide enough to offer a minimum 20 mm support to all four edges of the board.
Drywall screws or, alternatively, galvanised clout nails, long enough to allow a minimum 25 mm penetration of the timber, should be placed at 150 mm centres and not less than 10 mm from the edges of the board. They should be driven straight with the heads embedded just below the surface of the board. Care should be taken not to overdrive nails / screws. Timbers should be treated where appropriate.

Mechanical Fixing to Metal Furring Systems

Kooltherm K18 Insulated plasterboard in metal stud wall applicationK18 Insulated Wallboard can be fixed by the use of proprietary metal framing systems to brick, block or concrete walls. The metal frame should be fixed to the masonry or concrete wall in accordance with the manufacturer’s instructions to provide a true and level base for the board.
The frame should be set vertically at a maximum of 600 mm centres to coincide with board joints and midpoint of board. Short lengths of metal framing should be fixed horizontally between the vertical pieces at skirting level, at the midpoint of the board and just below the ceiling or soffit level.
Provision for horizontal services behind the board can be made by the use of two pieces of metal framing set no more than 300 mm apart. K18 Insulated Wallboard should be screw fixed to each metal framing section with self drilling and tapping, countersunk, surface coated (to avoid corrosion), screws placed at 150 mm centres.
Screws should not be sited less than 10 mm from the edges of the board. The screws should be driven straight until the heads are slightly below the paper surface of the plasterboard facing. Care should be taken not to overdrive screws.

Mechanical Fixing to Timber Joists or Rafters

Kingspan K18 Kooltherm K18 Insulated plasterboard in a ceiling applicationK18 Insulated Wallboard may be used to line ceilings. Installation is similar to that of standard plasterboard.

Boards must always be placed with the long edge running across the joists, rafters or battens and all edges must be supported.

Timbers must offer a minimum 20 mm support to all four edges of the board. This will necessitate the use of noggings placed between the joists to coincide with the long edges of the board.

Drywall screws or, alternatively, large–headed galvanized / sheradised clout nails should be used to fix the board. These must be long enough to allow a minimum 25 mm penetration of the supporting timber, and be placed not less than 10 mm from the edges of the board and be spaced at 150 mm intervals along all supporting timbers.

Mechanical Fixing Directly to Masonry Substrates

This method is for application to fair finished brick, block and concrete cavity walls where K18 Insulated Wallboard is to be finished with gypsum plaster. The wall should be sound, dry and level (as surface irregularities may impede fixing of the board). The board should be fully restrained using mechanical fixings. The number and type of such fixings should be in accordance with the fixing supplier’s recommendations, and should be evenly distributed over the whole area of the board. Fixings should not overlap board edges.


Tapered edged boards allow the employment of standard dry–lining techniques. A plaster skim finish can also be applied to the boards. The finishing should be carried out in accordance with the specified manufacturer’s instructions, particularly in relation to the need to allow thorough drying of the plaster prior to decoration.

Fire Stops

Current Building Regulations / Standards should be considered with regard to the requirements for and provision of fire stops.

Contact Manufacturer

Kingspan Limited

Kingspan Kooltherm Phenolic Foam, Therma PIR, and Styrozone Polystyrene range of rigid insulation boards

Pembridge, Leominster, Herefordshire, HR6 9LA

Kingspan Technical Advisory Service.

Telephone: 01544 388 601 - Fax: 01544 388 888
Email:  /
Web sites: Kingspan Home Page / Kingspan U-Value Calculator.

Contact us

Insulation Online Limited

Sales Office only:

39 Normandy Road, Worthing, West Sussex, BN14 7DX, UK

Telephone: 0333 8000 828