Concrete - Basic Material-I PDF

2.2 CONCRETE Basic Material- I Semester I, B.Voc Interior Design Module 2.2.3  Concrete What was once used in residential architectural design for foundations and subfloors has come from behind the walls and u...

2.2 CONCRETE Basic Material- I Semester I, B.Voc Interior Design Module 2.2.3  Concrete What was once used in residential architectural design for foundations and subfloors has come from behind the walls and under the house to become a pleasing and important part of modern interior design. Best remembered for its use in dreary utilitarian parking garages and unsightly apartment blocks, concrete has been transformed through the use of sophisticated colour and finishing techniques to be the main attraction in many residences around the globe. Avant-garde interior designers and architects began using exposed concrete as a final interior finish some decades ago, and most of them have never looked back. The bold, muscular look of concrete is what appealed to designers for use in pared-down minimalist interiors. The very energy it exudes gives new life and interest to otherwise empty and bland interiors. In the right setting, with the right finish, concrete countertops and work surfaces take on an almost monumental beauty, completing the interior design. With new techniques, concrete can be moulded to form bathtubs, sinks, and other vessels within the home. Floors and walls take on a new depth and a sense of the elemental with improved incising and casting techniques, and the lighter weight of today’s concrete makes it an easy-to-install alternative to stone. Concrete is cheap to produce, easily moulded into various shapes, and very strong. Like stone, it absorbs and releases heat slowly and is often used in areas for passive solar heat loss and gain. The many attributes of concrete are functions of the basic mix. Sand, water, gravel, and Portland cement are combined to achieve different densities, weights, performance characteristics, and appearances. Some environmentalists suggest using fy ash, a by-product of coal-powered factories, instead of Portland cement to reduce carbon dioxide emissions. Concrete is fireproof and virtually indestructible when properly fabricated. Although cold and hard, it is naturally moisture and insect resistant. If not sealed properly, it can stain easily, but otherwise requires little or no maintenance. Concrete can be laid on-site and is also available precast into slabs, blocks, tiles, and thin wall panels. Lighter concrete blocks have a better insulation quality than heavier blocks, and newer, translucent concrete allows light into otherwise dark interiors. Concrete should be mixed by professionals, and protective clothing should always be worn when working around fresh concrete as it can burn the skin if splashed. Concrete must cure fully before it can be used and should be treated if exposed to prevent it from continually shedding or breaking down into fine particles. The vast majority of concrete used in residential construction is cast on the site where the final product will be used. For new construction, the need for a spacious area in which to fabricate the concrete, move it to the site of the pour, and let it cure for up to four weeks is not a problem. When the material is to be used in an existing interior, the challenge of where and how to mix, move, and pour the material is exacerbated by close-in walls and existing finishes that need protection. A professional or very experienced do-it-yourself is the best choice to fabric the mix of sand, water aggregate, and cement. Too little sand or too much water and the concrete will be too dense and possibly not strong enough. Too much cement will cause cracking as the material dries. Different types and proportions of aggregate (sand and gravel) also affect the appearance. The more aggregate in the mix, the less dense the finished product. Standard concrete is grey; whiter concrete is made using white cement and white gravel. Qualities of concrete Concrete can be transformed into a structural material by pouring it over steel rods, wire, or mesh. It is used extensively for foundations and structural supports. Although concrete sets in hours, it takes up to a month to cure properly, and some areas might have to be out of bounds for a time. The temperatures in these areas must be stable and well over freezing at all times in the curing process. Concrete will not set if mixed on or near the freezing point. Concrete can be coloured by adding pigments to the base mix as it is manufactured. It also stains easily. Mixing cement with water causes a chemical reaction and the wet concrete, if splashed onto the skin, can burn.  Use of Concrete Concrete is used to create foundations and smooth subfloors for heavier materials such as stone and ceramic and can be used as the finished flooring, as well. Poured with mixed-in colour and a smooth finish surface, concrete creates warm and interesting flooring. Concrete is suitable for an underfoot-heating element. Concrete can be poured into moulds and allowed to set. The moulds, usually wooden or possibly metal, support the concrete while it sets and is then removed. Various patterns, shapes, and textures can be worked into the mould to create an imprint on the finished item. Concrete is used for countertops, floors, sinks, tubs, tables, and work surfaces. Finishing A smooth surface is achieved by finishing with a sand and cement layer. Elements of all kind’s stone, shell, and glass can be inserted into the wet cement and, when honed, become a feature of the final installation. This is used very effectively on counter-tops and in sinks and tubs. Special floor paints in a wide range of colour add to the design choices available for concrete finishing. Concrete is porous and should be sealed with a self-levelling acrylic or epoxy resin for a glossy, strong, and chemical- resistant finish. Concrete can be made nonslip with the application of industrial toppings applied by a professional. Concrete block is lighter in weight due to its honeycomb design. It is also higher in insulation properties and is well suited for exterior walls, partitions, and small structures. Concrete tiles can be textured to resemble stone, coloured to match any interior design, and come in various thicknesses. Large slabs for external use are thicker and weather resistant. Thinner tiles are used like ceramic and stone tiles, are thinner than exterior tiles, and are installed on a solid subfloor with mortar or grout between the joints. Panels of precast concrete come in a range of thicknesses and can be used for exterior and interior applications. Although thin tiles of concrete can be attached with adhesives, thicker panels must be secured in place by metal supports. Decorative concrete tiles are available in a wide range of colour and shape. They can be used outdoors for patios, pathways, and edging or indoors as flooring. Textures may be honed smooth or ribbed, and the grouting can be part of the overall colour or a contrast shade. With flooring, the subfloor must be strong enough to bear the weight of the concrete tiles or slabs and must be smooth, dry, and even. The addition of pattern or colour will enhance the rather bland and basic look of unadorned concrete flooring.