Items Tagged with: Div07

Roof decking pavers have created new opportunities for otherwise lost and unusable spaces.  Roofs and decks now have the ability to be functional, attractive exterior pedestrian plazas and living environments.  Pavers can be installed on roof decks and promenades, terraces, balconies, patios, plazas, arenas, roof gardens, and even on mechanical access walkways.  Roof decking pavers come in a wide variety of colors, finishes and textures.  Because of it's durability and strength, concrete is the primary material used to produce roof decking pavers.

Modified bituminous roofing systems are available in two materials which are commonly used today for low-sloped roofing applications: Atactic Polypropylene (APP) and Styrene-Butadiene-Styrene (SBS). The primary purpose for both of these materials is to provide the weatherproofing cover for the roof assembly. Crude bitumen is a hydrocarbon created naturally from petroleum, and modified bitumen is a blend of other organic materials with a polymer additive of either atactic polypropylene or styrene butadiene styrene. Atactic polypropylene is a plastic additive that gives rigidity and tear resistance to the final product, and styrene-butadiene-styrene is a rubber additive that gives more resilient benefits. These blends are then applied to a base material of polyester or fiberglass. Sheet asphalt paving (mastic asphalt concrete) makes up the majority of bituminous products used in the U.S. Even though bitumen is sometimes referred to as tar or tar-like in its consistency, it is not to be confused with tar. Tar is a product manufactured from coal and is not used as a part of this roofing system.

Bentonite is a type of clay having the unusual characteristics of cohesion, binding, sealing, and thickening. It is usually gray in color and when processed has the consistency of fine powder, similar to cement or flour. When bentonite is installed below grade as a waterproofing membrane, it becomes hydrated with the moisture that is naturally present in the soil and forms an impermeable barrier that absorbs and expels water and most chemicals, such as acids and salts (sodium bentonite). Bentonite can expand and contract an infinite number of times and is capable of absorbing seven to 10 times its own weight in water, swelling up to 18 times its dry volume. However, for bentonite to function properly as a waterproofing barrier, it is extremely important that this barrier remain under a constant minimum pressure of 30 to 60 pounds per square foot (PSF).

Slate is a very stable natural material.  It is thermally stable and not readily changed by chemical or biological reaction.  Slate comes in various colors, usually in shades of pale grey to dark grey, although it may also be purple, green or cyan depending on where it's mined.  Slate is quarried all over the world, either by open-pit mining or by tunneling. In the U.S., slate is extracted from eastern Pennsylvania, Virginia, New York, Vermont and Main. This fine grained material was originally composed of clay or volcanic ash in prehistoric ocean beds.  Through millions of years of pressure and extreme heat, known as metamorphism, it turned into what is known as slate. Because of the natural way in which slate can be split along its planer axis and yet still maintain its integrity, slate has been adapted very well to the building industry.

The purpose of roof and deck insulation is to provide resistance to thermal energy. When insulation can inhibit the flow of thermal energy, the result will be a greater capacity to conserve heating and cooling energy. Heat flows from hot to cold due to conduction, convection and radiation. Heat is measured using the British Thermal Unit (BTU) where a BTU is the energy required to raise the temperature of one pound of water by one degree Fahrenheit. Therefore, a material with a higher R-value will provide greater thermal resistance. The roof of a building can be the structure's largest surface area, and consequently the area in which heat has the greatest opportunity to escape. With the correct type of insulation specified as part of the roof system, it will meet energy performance requirements and codes and provide many years of fundamental performance.

Firestopping seals and protects openings and joints in fire rated wall, floor and ceiling assemblies.  It is a term used in the construction industry that includes several different components.  These components make up what is known as a Passive Fire Protection (PFP) system.  PFP are one of three systems that make up building fire safety;  Active Fire Protection (AFP) and Fire Prevention are the other two systems.  When there is an unprotected opening in a fire rated wall, floor, and/or ceiling assembly, the PFP system becomes compromised, allowing smoke, poisonous gases and fire to spread.  Due to the fact that any number of building materials can penetrate a fire rated assembly, including electrical, telecommunications, mechanical, plumbing and structural elements, there are a variety of firestopping materials specifically designed for each application.

Gutters and downspouts are an important part of any roof drainage system, used to control rainwater runoff. Gutters and downspouts protect a structure from serious damage, as moisture in the roof, walls and foundation of a building can lead to many problems, including mold and mildew issues. The gutter is the horizontal component designed to collect and channel rainwater away from the roof, directing it to the downspouts. The downspout is the vertical pipe used for carrying the collected rainwater away from the structure. The outlet of the downspout can terminate above or below ground. In above ground terminations, splash blocks are often used to direct rainwater away from the foundation of the building. Many buildings and sites utilize a network of underground piping which connects the downspouts to a city or municipal underground storm system.

Standing seam sheet metal roofing refers to a flat metal panel that is seamed or interlocked together along the edges of a turned up vertical leg.  There are four basic ways the vertical legs of adjoining panels can be secured or seamed. They can be mechanically seamed, or have snap together seams, tongue and groove seams, or hooked seams. Standing seam metal roofing panels can be custom fabricated in the shop or roll-formed on-site. Metal roof systems fall into two categories: structural and architectural.  A standing seam sheet metal roofs is an example of an architectural system. These roofs are designed to be a watershed system rather than a water barrier system, and require slopes of 3:12 (or 14 degrees) or greater.  Architectural roof panels generally have a flat surface with a ¾ inch to 1 ½ inch raised vertical seam running the length of the panel.

Ethylene Propylene Diene Monomer, better known as EPDM, is a common roofing material in the construction and building industry. In low slope roofing applications, EPDM is considered one of the three thermoset types of flexible single ply sheet materials. Chlorosulfonated Polyethylene (CSPE) and Polyisobutylene (PIB) are the other two types of roofing in the thermoset category.

Weather barriers keep outside weather out and conditioned interior air in.  A weather barrier is part of the wall assembly; it prevents the passage of moisture, rain and wind through critical areas of the walls and roof, and protects vulnerable building components from deterioration.