There has been lively debate in recent years on the relative fire performances of foam-filled composite panels versus mineral-wool built-up systems.
Composite-panel manufacturer Kingspan feels that when it comes to insulated roof and wall systems, the tougher line taken by insurers regarding industrial and commercial property business risk is based on misconceptions. The company points out that, of 149 fires in the 10 years to 2002, PUR/PIR insulated roof and wall systems were present in only two buildings, while in the same period, 124 fires occurred in traditionally constructed buildings and a further 22 in those with polystyrene sandwich composite systems.
Kingspan's Architectural Wall Systems offer the crisp, modular look currently in vogue for commercial and retail applications. These can be enhanced by roof panels curved to a 150mm minimum radius. The prefabricated panels minimise the potential for thermal defects, while the closed-cell insulants, being thinner than their mineralwool counterparts, result in thinner constructions.
Fire resistance is a topical issue and it was a theme many exhibitors were keen to discuss. This included Isothane, manufacturer of Pithan 0, which not only allows fast-track upgrades to Part L requirements, but is also Class 0 fire-rated and suited to a host of building interiors.
Isothane manufactures a variety of urethane systems, including Technitherm, a structural PUR foam that can be injected into cavities both to insulate and to strengthen a wall with failing wall ties. The product is claimed to make a property three times stronger in gale-force winds than when wall ties have been used. This is broadly similar to Isofoam CRF, a PUR cavity-reinforcement foam exhibited by Baxenden Chemicals. Used to treat wall-tie failure, Isofoam CRF bonds together the inner and outer cavity leaves over their whole surface area. Such systems are particularly useful where the masonry or mortar joints of either leaf are in poor condition. A typical U-value of 0.3W/m 2infinityC can be obtained with a 60mm cavity.
Exhibitions can provide the ideal opportunity to launch new products, although this was not the case at BRUFMA. However, a relatively innovative roof adhesive, called Insta-Stik, was exhibited by the Dow Chemical Company. Dispensed from a pressurised container, the single-component, polyurethane roof adhesive is used to fix compatible roof insulation boards to a variety of substrates, including other insulation boards. This eliminates metal fasteners, which is useful where the integrity of wood decks needs to be maintained, or on metal decks, where thermal bridging through fasteners is eradicated. Pre-drilling of concrete decks for fasteners is also eliminated.
Also present was Eurobond Laminates, a company that specialises in the design and manufacture of insulated panels, particularly for food-processing facilities, cold stores and distribution centres. Eurobond recently announced that its new Eurofoam PIR panel has passed Loss Prevention Council Standard Test LPS 1181(Reaction to Fire). The polyisocyanurate core is deemed to offer better fire performance than modified polyurethanes.
Furthermore, because the panel requires no intermediate fixings, it is quicker and easier to install than conventional LPS 1181 panels, the company claims.
Recent years have seen healthy growth in the use of foam-filled composite panels, particularly as an initiative-obsessed construction industry shifts the focus onto prefabrication, time/cost savings and better site quality. However, detailed generic information on composite panels has been sparse. Redressing the balance, Huntsman Polyurethanes exhibited a new publication called Sandwich Panel Construction (ISBN 3-433-01617-8). Written by Rolf Koschade, the well-illustrated, 400-page book forms a complete reference source to planning and installing composite panels and should be of interest to the entire building team, including building owners.
Steadmans is a company that has experienced phenomenal growth since its early beginnings as an agricultural blacksmith.
Today, it supplies cladding materials throughout the UK and Ireland. In addition to profiled metal sheets, purlins and flashings for roofing and cladding, the company manufactures the AS composite panel system. Faced with a Plastisol- or polyester-coated alu-zinc sheet, the rigid PUR foam-filled panels come in various colours and thicknesses and are available in any length compatible with transport constraints.
No tangible products were displayed by BOC Gases, although its blowing agents are used in the manufacture of PUR insulation.
The company is developing more environmentally acceptable alternatives to HCFCs which, due to their significant ODP, are to be phased out under the Montreal Protocol. In contrast, the zero ODP of pentanes and pentane blends - such as Cyclo-plus and Iso-plus launched recently by BOC - makes them suitable alternatives to satisfy the growing demand for polyurethane foam blowing agents.