Whilst the basic panel method described above can be engineered and manufactured either on a suitable platform on site or in a workshop from materials readily available from the timber merchant, insulated panels are usually manufactured in a factory and under a proprietary trade name. One such is made by Unilin Systems and this can be seen in Fig. 4.12. The product consists of conventional softwood rafters and a ceiling panel of various materials; between the rafters is a waterproof insulation filled to within 20 mm of the upper surface of the joist to allow a ventilation gap. There is no top sheathing. Each roof is individually engineered by the company using standard specifications and components. The panels can be up to 1210 mm wide and 8 m long. They require a gable and purlin type construction running as they do from ridge over purlin to wall plate. On long roofs of course the intermediate support for the purlins can be provided by a principal truss. The method can accommodate roof windows and dormers. In its most basic form, the ceiling panel can be moisture re-
Fig. 4.12 Insulated panel roof.
sistant plasterboard, progressing through a whole range of materials including pre-finished chipboard to tongue and groove boarding and acoustic panels. Thus it can be seen that the ceiling is part of the waterproof structure, the panels being sealed at their longitudinal and horizontal joints with waterproof foam during assembly. Final waterproofing is carried out with tiles and battens in the conventional manner. All fixing for panels to purlins and wall plate are specially developed and provided with the package. Again this method provides a completely free, triangular attic space with no ties, for the designer and occupants to use as they please. Unilin Systems panels are manufactured in Belgium and distributed in the UK by Milbank Roofs, full details of which can be found in the bibliography.
Was this article helpful?