Steadmans - Roofing & Cladding Systems Slate Effect Details

Slate Effect Insulated Roofing Systems - Details - Performance

Thermal Bridging & Fixings

The strength of the panels minimises the number of supports and fixings required to restrain them, consequently, the fixings produce negligible heat loss, which is confirmed by thermographic imaging.

Air & Moisture

The thermal performance of an insulant can be significantly compromised by air movement and by moisture. Air currents around and through fibrous insulation will disturb the air in the pockets between the fibres and reduce performance. In some systems, air leakage can also transport water vapour into the roof or wall cladding, where it can condense on the underside of the weather sheet before being absorbed by the insulation. Liquid water can increase the rate of heat loss through insulation ten-fold: should the water freeze there will be an an even greater loss of heat.

The closed cell structure of the insulation core to Steadmans' AS35 Panels overcomes all of those problems. The core is not susceptible to air movement and is also resistant to water vapour, whether transported by air movement or by diffusion. When combined with the impervious panel linings that means there is no risk of condensation affecting the panels.

Environmental Performance

AS35 insulated panels provide high levels of sustainability and environmental performance compared with alternative solutions. The creation of a thermally efficient building envelope with low conductivity and minimal air leakage reduces energy usage and therefore CO2 emissions: it also contributes towards lower building running costs.

On a broader assessment, The BRE Green Guide to Specification and Life Cycle Assessment suggests the PIR insulation core as having a positive environmental impact, with a Zero Ozone Depletion Potential (ODP) and Low Global Warming Potential.

Twin Skin Roof & Wall Profiles

Steadmans AS twin skin roof and wall systems consist of coated steel sheets rolled to six different profiles for roofs and walls. They offer rapid coverage and swift completion to give a high performance building envelope.

The external weather sheets are 0.5 or 0.7mm thick, and the liner sheets 0.4 or 0.7mm thick. The panels can be used down to a roof slope of 4º (6º with rooflights), and will form a Class B non-fragile roof assembly. The twin skin system can deliver U-values down to 0.16 W/m2K (requires 280mm of insulation with a conductivity of 0.040 W/mK), with only a limited amount of thermal bridging at element junctions.

Twin skin systems have very little risk of surface condensation and, when the impermeable liner sheets are correctly sealed, have little risk of interstitial condensation.

Meta-Slate

Meta-Slate is a slate-effect roofing sheet manufactured from 0.7mm, hot-dip galvanised steel to BS EN 10143:2006, with 300mm cover width, and supplied in lengths of up to six metres. Meta-Slate is embossed with a regular slate pattern and has a slate blue matt Nova coated upper surface and a grey epoxy coated underside. Joints between units are formed with Steadmans' unique lap joint system which allows easy adjustment during installation and forms a strong weatherproof joint.

Meta-Slate can be fixed to timber trusses, traditional rafters or metal purlins (with Steadmans metal truss), with fixings at a maximum 1000mm centres (800mm centres recommended). Lengths of Meta-Slate can be joined with a concealed joining plate, which does not have to coincide with supports, and can be cut with a standard power circular saw or jigsaw. Alternating lengths of Meta-Slate should be staggered to give a full slating effect.

Meta-SlatePlus

Meta-SlatePlus consists of AS35 insulated panels overlaid with Meta-Slate slate patterned roofing, to give a natural slate appearance with high thermal performance (see diagram below). Meta-Slate is laid directly onto the AS35 Panels and fixed to the panel crowns with 5.5 x 25mm self-drilling screws.

Accessories

Steadmans manufactures and supplies a wide range of accessories and complementary products, including:

Gutters: Pre-galvanised and pre-coated steel in units up to 10m long and 3mm thick.

Rooflights: Both site assembled in-plane rooflights to match twin skin profiles with U-values down to 2.2 W/m2K, and factory-formed in-plane rooflights for use with AS35 Insulated Panels which give U-values down to 1.0 W/m2K.

Flashings: To match panel profiles in Plastisol leathergrain, polyester, Nova, HPS200 Ultra or galvanised finishes. They can be supplied in lengths up to 6m in traditional profiles, or shaped to meet customer requirements.

Sealants: NFRC Class A butyl sealants, profile foam fillers and expanding foams for sealing profiles and components.

Zed Purlins & C Sections: Galvanised steel supporting structure for the installation of insulated panels and twin skin panels.