As a homeowner, local special trades contractors are very valuable assets you cannot afford to be ignorant about. These are people who are involved in particular construction activities like painting, plumbing and also electrical work. The work that they do involves alterations, repairs, maintenance, additions or new work. The construction jobs are usually performed at job sites but some may involve some prefabrication that is done in their shops. This category of contractors includes various contractors who specialize in specific areas of construction. A construction company usually has plumbing, air-conditioning and heating contractors who are involved in the installation, servicing and selling air-conditioning, heating, and plumbing equipment. The type of work can include duct fabrication, installing refrigerators, sprinklers and environmental controls. Wall covering and painting contractors will assist you when it comes to the painting of the interior and exteriors and covering of the interior surfaces in your home. They also work on bridges, ships and on roads. Masonry and stone contractors will perform any stone work you require. They construct foundations made of stone, brick, marble, glass, granite and slate. Electrical contractors will come in handy when you need to install or service any electrical equipment. There are also some contractors who specialize in installing floor tiles, carpets, linoleum and resilient floors.