PHENOLIC INSULATION BOARDS

PF phenolic insulation boards (Phenolic Foam) are lightweight but strong thermosetting plastics and are considered to be one of the best rigid, closed-cell structure materials for thermal insulation at present being up to 50% more effective than other common insulation materials such as PIR. Closed cell content makes it highly resistant to water penetration. In fact, it is non-wicking material. This means that if water enters the insulation system due to the vapour barrier becoming punctured, any moisture ingress is limited and confined to the punctured area. This ensures moisture does not build up and compromise the whole system. Any moisture ingress is limited and confined to the punctured area. As they’re closed cells they shouldn’t absorb moisture or water vapour, unlike open cell products. Phenolic insulation achieves a lambda value of just 0.018 W/mK across all thicknesses. High density boards have a good compressive strength and are suitable even for floors. Phenolic foams are produced with densities in the range of 35 kg/m³ to 160 kg/m³ and are often used in particularly damp environments such as bathrooms and toilets. Phenolic boards will likely be the most expensive of all the rigid foam insulation options available on market, however being low thermal conductivity insulation enables high levels of thermal performance to be achieved utilising thinner sections of insulation. The exceptionally low thermal conductivity of closed cell phenolic foam boards means that appropriate insulation efficiency can be achieved with the thinnest possible material. Phenolic foam is typically made in 80kg/m3, 120kg/m3 and 160kg/m3 densities. It is produced in board form in various sizes and thicknesses. The most popular thicknesses are 25mm, 50mm and 100mm. 1m2 of the product is capable of supporting the weights: 80 kg/m3 64 tonnes, 120 kg/m3 112 tonnes and 160 kg/m3 225 tonnes. The boards achieve a thermal conductivity (λ–value) of: 0.023 W/m.K (15–24 mm), 0.021 W/m.K (25–44 mm) and 0.020 W/m.K (≥ 45 mm).

SHORT HISTORY OF PHENOLIC INSULATION

Phenolic insulation became popular in the 1980s as a thin board that could meet the increased energy saving demands of the day and fit within the constrained spaces older buildings offered for insulation. Kingspan, an Irish company has been producing and selling Kooltherm in Europe since 1992, introducing it in the USA in 2016. It was a response to the energy crisis, which called for greater insulation efficiency. As regulations required higher R-value insulation in roofs, a demand arose for material which offered both fire resistance and high R-value, while not requiring a full roofing re-build to accommodate its thickness.

WHAT IS PHENOLIC INSULATION MADE OF?

A wet foam mix is added directly to the bottom layer of facing. It then expands to meet the top layer. This is then cooked under pressure and cured in a second oven. When it’s ready, the phenolic insulation boards are cut to the right size and packaged up. It means that PF board is manufactured by a process in which a plastic foam forms an insulating core between two flexible tissue faced layers. It has a high closed cell content and fine cell structure.

PHENOLIC INSULATION APPLICATION

Phenolic foam is a uniquely versatile material being suitable for a large range of applications. It can be used in a variety of roof, wall and floor applications, which makes it a great solution for a range of constructions. Used extensively in the building industry for a number of application areas including roofing (Xtratherm Safe-R SR/PR), cavity board (Xtratherm SR/CW), external wall board (Kingspan K5), plasterboard dry linings systems (Xtratherm Safe-R SR/TB or Kingspan K118) and floor insulation (Kingspan K103 or Xtratherm SR/UF Safe-R). Phenolic foam is also used in a number of highly specialised applications including fire doors, highly fire resistant panels and for insulation in surface ships, off-shore installations and submarines. It has also been used in heating, ventilating and air conditioning applications for many years.

PHENOLIC INSULATION FIRE RATINGS

Phenolic insulation boards have the highest fire rating among many organic insulation materials. It can, in an appropriate form, achieve all the European fire certifications - UK Class O and Dutch NEN 6065/6066 Class 1. Generally speaking, the board is fire-resistant, flame-retardant, non-combustible in case of open flame, smoke-free, non-toxic, and non-dropping. In fact, phenolic foam used as composite panels can achieve up to 2 hours fire resistance rating in the 3m furnace test. The fire performance of phenolic foam is exceptional. It combines zero or very low flame spread with negligible smoke emission and a very low level of toxic gas emission. Foam evolves exceptionally low smoke when exposed to fire and is capable of meeting or exceeding all international building regulation requirements. Toxic gas emission from phenolic foam is generally limited to carbon dioxide and carbon monoxide with very low levels of other gases. Phenolic foams can achieve very low toxic gas ratings in tests such as UK Naval Engineering Standard NES 713. The superior fire performance of phenolic foam is being recognised and this is leading to increased market share in these areas.

PHENOLIC INSULATION VS PIR

Phenolic boards have a slightly higher R-value and a slightly thinner profile than PIR boards due to the manufacturing process. While PIR offers the lambda value of 0.022 W/mK, phenolic closed cell foam offers 0.018W/mK. For comparison, Celotex makes polyisocyanurate rigid foam, so perhaps phenolic is only 10% better then PIR. Moreover, PF boards rasp beautifully, where PIR crumbles. However phenolic boards do tend to be more expensive but on other hand offer the thinnest insulation boards for a given specific u-value. As they’re closed cells they shouldn’t absorb moisture or water vapour, unlike open cell products. PIR insulation boards combine thermal efficiency with an economical price point, although the slightly better thermal performance of phenolic foam may justify the increased cost if depth in the floor construction is at a premium.

PHENOLIC INSULATION PROBLEMS

Phenolic should always be installed above the damp proof membrane (DPM). It is never recommended to lay them exposed directly to the ground. Long term exposure to moisture can result in facings – particularly composite ones featuring kraft paper layers – breaking down, to the detriment of the product. Phenolic insulation is susceptible to decay and causes pipework corrosion when it gets wet. Therefore, measures should be taken to prevent water ingress. Pipework should be properly installed to avoid leaks and all welds should be painted with corrosion resistant paint prior to joint insulation and casing work. Phenolic insulation systems were put in place that the industry realized it creates sulfonic acid when exposed to humidity or direct moisture, like when a roof leaks. In a short time, the acid begins to eat holes in standard painted deck and/or galvanized decks. Phenolic insulation also has a history of crumbling and easily crushes when walked on, leaving a residue on the decking. In order to prevent corrosion in this application, we would need to remove all the residue, which is not practical. But corrosion can’t form without oxygen, moisture and a catalyst. In this case, the catalyst is the Phenolic insulation residue and the sulfonic acid. So the easiest way to prevent corrosion is to use a high-build barrier type coating to stop moisture from contacting the sulfonic residue and steel.

PHENOLIC INSULATION KINGSPAN AND XTRATHERM MANUFACTURERS

There are only a few main players on the market - Kingspan® followed by Xtratherm®. Two of them started their activities in Ireland. Perhaps because many houses in Ireland, particularly those built prior to 1980, were not energy efficient and poorly insulated. While Kingspan offers only Kooltherm K-range, Xtratherm seems to offer a bit more. Xtratherm has products for specific projects. Depending on the application, you can choose between:

Soffit phenolic boards | Drylining  | Cavity wall phenolic boards | Florring phenolic boards | Rainscreen  phenolic boards | Roofing phenolic boards | Steel and timber frame

XTRATHERM®

Xtratherm SR/CW Cavity Wall Insulation Board Xtratherm Safe-R - is a top-class phenolic foam rigid cavity insulation board with a low emissivity foil facings designed for use in traditional masonry walls.

Xtratherm Safe-R SR/TB Insulated Plasterboard is a combination of premium phenolic insulation core with a composite foil facing bonded to 12.5mm tapered edge plasterboard for drylining internal walls.

Xtratherm SR/UF Safe-R Phenolic Foam Underfloor Insulation Board – is a top-class rigid phenolic foam insulation board with a low emissivity aluminium foil facings designed for ground supported floors, suspended floors and underfloor heating (UFH).

Xtratherm Rainscreen Cladding Xtratherm Safe-R SR/RS is a high-class rigid phenolic insulation board with a low emissivity foil facings designed for ventilated rainscreen cladding applications in new build and refurbishment projects.

Xtratherm Safe-R SR/PR is a high-class rigid phenolic foam insulation board with a low emissivity foil facings designed for pitched roofs, sloped roofs, ventilated roofs, hybrid roofs and warm roofs.

Xtratherm Soffit Insulation Board Xtratherm Safe-R SR/ST is a high-class rigid phenolic insulation board with a low emissivity foil facings designed for structural ceiling applications.

Xtratherm Soffit Plus Insulation Panel Xtratherm Safe-R SR/STP  is a top-class two-in-one composite insulation board which provides an effective thermal and fire performance solution in structural ceiling applications for commercial and residential buildings.

Xtratherm Framing Board Xtratherm Safe-R SR/FB is a top-class rigid foam insulation board with a low emissivity foil facings designed for use with steel and timber frame applications up to 18m in height.

KINGSPAN®

The Kingspan Kooltherm K-range comprises the thinnest commonly used insulation products for any specific U-value. With a fibre-free rigid thermoset phenolic core, and a thermal conductivity of 0.018 - 0.023 W/mK, these are the most thermally efficient insulation products commonly used.

K103 Kingspan Kooltherm Floor - is an exceptional performance rigid phenolic foam floor insulation board with a glass tissue facings designed for suspended floors, ground supported floors and underfloor heating systems (UFH).

Kingspan Kooltherm K118 Insulated Plasterboard - Dry Lining Insulated Board is a top-class three-in-one product for internal wall insulation used as mechanically fixed and adhesively bonded 'dot and dab' insulated plasterboard.

Kingspan Kooltherm K5 Phenolic External Wall Insulation Board -  is a high-performance rigid thermal insulation board designed for external wall insulation behind traditional and lightweight polymer modified renders and dry cladding systems.

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

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