The Hotham is made from natural pumice that come from the Hekla Volcano in Iceland, compressed into blocks that function as natural insulation. No matter how hot the fire gets, the outer blocks stay at the same temperature. This preserves the external render. This also means that you may stencil or paint on the external render if your creativity guides you to do so. Installation BriefWe recommend a minimum 100mm thick reinforced concrete slab to bed the Hotham onto. The size should be at least 150mm wider than the Hotham on all 4 sides. All the pumice components to be joined with jointing adhesive using the application bags provided. Use a spirit level to check and level as you go. The finished joints should be 2-3mm thick. The external surface of the fireplace can be coated with the enclosed external render mix supplied and or painted with breathable waterproof masonry paint. They can also be customised with feature stone to suit your decor. Base Firebricks to be laid first, followed by the back bricks then the sides. Please allow the Hotham 72 hours to dry before using. Please note 75mm distance is required to combustible material. SpecificationsDimensions 1090L x 640W x 2250mm HFireplace Opening 940L x 515W x 720mm HWeight 960kgAccessories Log Store, Cooking Grill, Rain Cap,Chimney Extension BlocksMaterial PumiceWarranty 5 yearsDelivery To door or commercial depot Note: These are non-refunded products