Typical Industrial Building - Part 2
Flat roofing is most commonly found on industrial structures. The term flat is misleading, as flat roofs have some degree of slope for water drainage. Slope refers to the degree of rise. For example, a 4” by 12” slope means that the rood rise four inches in every 12 inches of horizontal run. Industrial flat roofs have a very low slope, as compared to higher slopes in residential property. Residential roofs are not watertight, but rather shed water given the high slope.
The industrial flat roof must be watertight, along with all associated joints and seams. Typically, roof decking in newer building is steel or concrete. Wooden decking can be found in older structures. A typical, new industrial roof has (from bottom to top) a steel decking and a vapour barrier to prevent interior moisture from penetrating insulation placed above it. Above the insulation, a roof surface is applied. Several roof surfaces are available, with a built up roof (or a variation of it) being very common. The built up roof (BUR roof) consists of asphalt, felts and gravel. Successive layers of felt and asphalt are layered over the entire roof (e.g., four-ply roof has four layers of felt and asphalt). The final coat of asphalt is then covered with a granule-based layer of mineral aggregate.
BUR roof life is dependent on many factors such as weather conditions, quality of materials used, number of plys installed and amount of roof foot traffic. A properly installed, high quality 4-ply roof should last about 15 to 20 years. In recent years, other types of roofing have been introduced such as rubber and vinyl waterproof membranes that are laid directly over the insulation and then held down by aggregate. These membranes are made in large sheets with any season properly sealed on-site.
Floor load refers to the ability of a floor to support a live load. A live load generally consists of three components:
· The eight arising from the assembly of persons;
· The weight of the accumulation of equipments and furnishings; and
· The weight of stored materials.
Live load should be clearly differentiated from a dead load. Dead load refers to the weight of the structural member itself; i.e. the materials incorporated in the structural member and permanent equipment.
The Ontario Building Code sets out live load requirements according to use and occupancy that are normally expressed in terms of pounds per square foot (or the metric equivalent) for various types of uses. The minimum specifications are typically stated as a uniformly distributed live load on an area of floor in relation to its particular use. The building code will set out differing minimum specifications are typically stated as a uniformly distributed live load on an area of floor in relation to its particular use. The building code will set out differing minimum specifications for equipment, service, assembly, office, garage, factory and corridor areas. Live loads requirements apply to both residential and commercial structures. Load requirements apply to both residential and commercial structures. Load requirements also apply to other building components such as roofs, balconies, elevated walkways and footbridges.
Heating ventilation and air conditioning (HVAC) applies to all commercial buildings, but warrants highlighting when discussing industrial buildings features/characteristics. This is particularly vital with certain industrial uses that must maintain continuous air quality, along with temperature. Industrial HVAC mechanical unit(s) regulate the even distribution of heating, cooling and fresh air throughout a building. A broad range of HVAC systems are used in the marketplace. Industrial HVAC systems are often roof mounted with supply air diffusers strategically placed within that ceiling, along with return air ducts. Following are selected components:
Air handler: the blower or series of fans within an HVAC system used to love heated or conditioned air through the structure, normally by means of duct work.
Condensing unit: Normally situated outside the structure, the condensing unit contains a compressor that compresses coolant, thereby providing the cooling effect within an air-conditioning unit.
Ductwork: A series of ducts used for the distribution of warm or cool air throughout a structure to various rooms, offices and work areas. The ducted system permits the return flow of air back from various portions of the structure to the HVAC unit.
Roof Top HVAC: A large HVAC unit mounted on the roof of a structure that provides cooling and heating for the structure.
Unit heater: A large interior, roof-hung unit that heats open areas.
A loading dock is an area found primarily in commercial and industrial structures designed for the on-loading and off-loading of products, usually at truck level height. Common dock features are itemized.
· Shelters are flexible, enclosed canopies designed to reduce wind drafts between trucks and interior areas.
· Levellers provide an adjustable platform between trucks and the permanent docking areas. Levellers are rated in terms of lift capacity and are normally driven by hydraulic motors.
· Wells service inclined dock areas for structures built at grade level. The inclined areas require storm drains and, therefore, are not as popular in modern buildings.
· Dock high loading offering direct loading has become more popular. The dock height will depend on the type of facility being serviced; e.g., a courier company will have lower dock levels to accommodate package vans, while a food distribution terminal will have higher docks for tractor-trailer units.
· Grade level loading for areas that are level with surrounding parking and related areas permit direct access to and from the structure by forklifts and other vehicles. Various big box retailers provide grade level loading areas for customer pickup; e.g., electronic, building materials and furniture stores.
Sprinkler systems are common in all commercial buildings, but warrant emphasis when discussing industrial uses. This system of interconnected popes throughout all or a portion of an industrial building provides water as a fire protection system. Most sprinkler system can be manually operated or automatically controlled by smoke alarms or other head sensitive detectors. The term sprinklered (often used in building codes) means that a building is equipped with a system of automatic sprinklers.
The sprinkler system consists of various pipes, risers, mains and sprinkler heads. Five types of sprinkler systems are typically found in the marketplace.
Wet pipe: Filled with water under pressure. A plug will melt at high temperatures and release water immediately
Dry pipe: Contains compressed air extending from a sprinkler head to a dry pipe valve. When the plug melts, the air pressure drops and water flows through the sprinkler head.
Pre-action: Contains air that may or may not be under pressure. The water is held back by the automatic valve operated by a head-activated device and is generally more sensitive than a normal automatic sprinkler.
Deluge: Used where unusual fire hazards exist and large quantities of water are needed quickly over large areas. Valves can be co-ordinated to open either manually or automatically by heat-activated devices.
Combined Dry Pipe and Pre-Action: Employs automatic sprinklers attached to a piping system containing air under pressure
Nearly all automatic sprinkler alarm systems include a trigger operated by a flow of water that sets off a water or electric alarm. Both systems can be connected to a local fire alarm. The release of carbon dioxide, a colourless, odourless, heavier-than- air chemical, has been a valuable system for extinguishing fires in electrical equipment, gasoline, oil, grease and paints. Since carbon dioxide leaves no residue, the area can be entered immediately.
A transformer is an electrical device that changes voltage through the transferal of electricity by means of electromagnetic induction, commonly associated with industrial property. Registrants will normally encounter three primary types of transformers.
· The pole transformer service (resembling a large pot) is located on a pole near the street and is generally used to provide relatively small size services (under 600 amps) to industrial, retail, office and investment properties.
· The mat transformer service is a larger cabinet style unit located on the ground, often directly adjacent to the building.
· The pad transformer service involves several mat transformers located on a pad.