A multi-layer covering includes a flexible fabric layer. The fabric layer may be a fluffy blanket or a mesh. Where the fabric layer is a blanket it has a thickness of 2mm to 5mm, and is in the form of a batt or weave or spun bonded layer, and defining gaps between the strands of in the blanket. Where the fabric layer is a mesh the spacing between adjacent strands of the mesh is 3mm to 20mm. The multi-layer covering further includes a metallic reflective foil (or paper) support layer, and a layer of adhesive protected by a peel-off backing layer for ease of applying the covering to a surface. When covering a wall, the covering is stuck to the wall and one or more protective coatings of paint render such as acrylic are applied to the blanket with a brush or roller or spray. Acrylic render paints typically includes a relatively thick mixture of cement, sand and acrylic polymer. The coarse sand and cement particles penetrate into the gaps between the fibres of the blanket or the holes in the batt as far as the face of the wall and saturate the blanket with acrylic render paint. The blanket provides an even surface when coated with render paint and avoids the need for extensive preparation of the wall. The covering may also be applied to floors, ceilings and roofs and covered with differing coatings, including acrylic render, plaster, paint, glue, and other surface treatments. The covering may be used to cover cracks and undulations in buildings and other structures.