Roofing Systems For Commercial and Residential
We are a team of roofing experts in St. George Utah that have passion for our work. Taking care of our customers is our #1 Priority. We use the best quality products for a long lasting roof for your home. We are one of the premier St. George Roofing Companies. If you want your roof done right we are the right choice.
Flat Roofing Systems
A flat roof is a roof which is almost level in contrast to the many types of sloped roofs. The slope of a roof is properly known as its pitch and flat roofs have up to approximately 10°. Flat roofs are an ancient form mostly used in arid climates and allow the roof space to be used as a living space or a living roof. Flat roofs, or “low-slope” roofs, are also commonly found on commercial buildings throughout the world. The National Roofing Contractors Association defines a low-slope roof as having a slope of 3-in-12 or less.
is a type of roofing system for buildings and tanks. It is used to move water off the roof. Membrane roofs are most commonly made from synthetic rubber, thermoplastic (PVC or similar material), or modified bitumen. Membrane roofs are most commonly used in commercial application, though they are becoming increasingly more common in residential application.
Synthetic Rubber (Thermoset) – This type of membrane roof is made of large, flat pieces of synthetic rubber or similar materials. These pieces are bonded together at the seams to form one continuous membrane. The finished roof’s thickness is usually between 30 and 60 mils(thousandths of an inch) (0.75 mm to 1.50 mm). The most commonly used thermoset membrane is EDPM. Other types of related materials are CSPE, CR, and ECR. Thermosets are widely used roofing materials due to their ability to withstand damaging effects of sun-rays and chemicals found on roofs.
Thermoplastic Membrane – This is similar to synthetic rubber, but the seams are typically heat-fused (welded) to form a continuous membrane. The ‘lap’ seams can also be fused with solvents instead of heat, and can be as strong as the rest of the membrane. Other related materials are CPA, CPE, EIP, NBP, PIB, and TPO. Thermoplastic membranes include a reinforcement layer that provides more strength and stability. The most common thermoplastic membranes are PVC (polyvinyl chloride) and TPO (thermoplastic polyolefin).
Modified Bitumen – This type of roofing is an evolution of asphalt roofing. It is made from asphalt and a variety of rubber modifiers and solvents. There are several ways of connecting pieces of this material. In a heat application process the seams are heated to melt the asphalt together and create a seal. There is also hot-mopped application, similar to how conventional built-up roofs are installed. Cold-applied adhesives and self-adhesive membranes are two of the more recent options. This material is also referred to as APP, SBS, and SEBS.
Advantages Over Asphalt Flat Roofing Systems
These three application types of membrane roofing show distinct advantages over the previously more common flat roofing method of asphalt and gravel. In asphalt and gravel application, it can be very difficult to create a proper seal at all seams and connection points. This can cause many roofs to leak early in its lifespan, and require much more maintenance. When installed correctly, newer materials are either seamless, or have seams as strong as the body. This eliminates much of the leakage concerns associated with flat roofing systems. Repairs for asphalt and gravel roofs can be hard, mainly because it is difficult to locate the exact point of a leak. Newer systems can be patched relatively easily, and breaks and leaks are easier to locate. Originally asphalt roofing required a layer of gravel above it for two reasons. First, asphalt with direct exposure to sunlight degrades much faster, mainly due to the expansion and contraction throughout a day, and also the damage created by UV rays. Second, asphalt needs weight above to hold it down, because it sits on the top of a building, instead of being attached to it. Each of the three newer types of membrane roofing systems contain materials that resist expansion and contraction, as well as reflect much of the UV rays. Also, because these membranes either lack seams or have strong seams, what expansion and contraction does occur does not create leaks and breaks at these seams. These newer roofing systems are also attached directly to the top of a building, which eliminates the need for excess weight above.
Roof Coating Systems For Commercial and Residential
A roof coating is a monolithic, fully adhered, fluid applied roofing membrane. It has elastic properties that allows it to stretch and return to their original shape without damage.
Typical roof coating dry film thickness vary from paint film thickness (plus or minus 3 dry mils) to more than 40 dry mils. This means a roof coating actually becomes the top layer of a composite roof membrane and underlying system. As such, the roof coating is the topmost layer of protection for the membrane, receiving the impact of sunlight (both infrared and ultraviolet (UV), rain, hail and physical damage.
Roof Coatings should not be confused with deck coatings. Deck coatings are traffic bearing – designed for waterproofing areas where pedestrian (and in some cases vehicular) traffic is expected. Roof coatings will only waterproof the substrates but will not withstand any kind of on going use by people or vehicles (such as walkways, patios, sundecks, restaurants, etc.).
Roof coatings are seamless and when installed correctly, can solve roof leaks on almost any type of roofing material.
There are exceptions: “professionals do not recommend using cool coatings over existing shingles. This technique can cause moisture problems and water damage because the coating can inhibit normal shingle drying after rain or dew accumulation, allowing water to condense and collect under the shingles.”
Field-applied reflective roof coatings can extend the useful life of nearly every roof substrate keeping a roof surface cool and providing a level of protection from the sun and weather.
However, coating asphalt shingles and built-up composition roofs requires more caution. The National Roofing Contractors Association’s (NRCA) director of technical services has stated “The roofing industry is aware of a number of issues that could have negative consequences for field application of coatings over asphalt shingle roof systems. Anyone considering this type of application should be aware of the concerns so they can weigh them against the benefits claimed in coating product promotional materials.”
Roof coatings can add 25 years to the service life of a roof and reduce the amount of discarded roofing materials that end up in landfills. The infrared image on the right shows 175 °F (79 °C) on the uncoated (black) section of the modified bitumen roof. The coated (white) section is 79 °F (26 °C). Field studies have shown that cool roof coatings can lower rooftop temperatures and reduce air conditioning bills.
Roof Tile Systems For Commercial and Residential
Roof tiles are designed mainly to keep out rain, and are traditionally made from locally available materials such as terracotta or slate. Modern materials such as concrete and plastic are also used and some clay tiles have a waterproof glaze.
Roof tiles are ‘hung’ from the framework of a roof by fixing them with nails. The tiles are usually hung in parallel rows, with each row overlapping the row below it to exclude rainwater and to cover the nails that hold the row below. There are also roof tiles for special positions, particularly where the planes of the several pitches meet. They include ridge, hip and valley tiles. These can either be bedded and pointed in cement mortar or mechanically fixed.
Similarly to roof tiling, tiling has been used to provide a protective weather envelope to the sides of timber frame buildings. These are hung on laths nailed to wall timbers, with tiles specially molded to cover corners and jambs. Often these tiles are shaped at the exposed end to give a decorative effect. Another form of this is the so-called mathematical tile, which was hung on laths, nailed and then grouted. This form of tiling gives an imitation of brickwork and was developed to give the appearance of brick, but avoided the brick taxes of the 18th century.
Slate roof tiles were traditional in some areas near sources of supply, and gave thin and light tiles when the slate was split into its natural layers. It is no longer a cheap material, however, and is now less common.
A large number of shapes (or “profiles”) of roof tiles have evolved. These include:
- Flat tiles – the simplest type, which are laid in regular overlapping rows. An example of this is the clay-made “beaver-tail” tile (German Biberschwanz), common in Southern Germany. Flat roof tiles are usually made of clay but also may be made of stone, wood, plastic, concrete, or solar cells.
- Imbrex and tegula – an ancient Roman pattern of curved and flat tiles that make rain channels on a roof.
- Roman tiles – flat in the middle, with a concave curve at one end at a convex curve at the other, to allow interlocking.
- Pantiles – with an S-shaped profile, allowing adjacent tiles to interlock. These result in a ridged pattern resembling a ploughed field. An example of this is the “double Roman” tile, dating from the late 19th century in England and US.
- Mission or barrel tiles – semi-cylindrical tiles laid in alternating columns of convex and concave tiles. Originally they were made by forming clay around a curved surface, often a log or the maker’s thigh. Today barrel tiles are mass-produced from clay, metal, concrete or plastic.
- Interlocking roof tiles – similar to pantiles with side and top locking to improve protection from water and wind.
- Antefixes – vertical blocks which terminate the covering tiles of a tiled roof
Roof Shingle Systems For Commercial and Residential
Roof shingles are a roof covering consisting of individual overlapping elements. These elements are typically flat, rectangular shapes laid in courses from the bottom edge of the roof up, with each successive course overlapping the joints below. Shingles are made of various materials such as wood, slate, flagstone, fibre cement, metal, plastic, and composite material such as asphalt shingles. Ceramic roof tiles, which still dominate in Europe and some parts of Asia, are still usually called tiles. Roof shingles are a very common roofing material in the United States, but may deteriorate faster and need to repel more water than wall shingles.
Roof shingles are almost always highly visible and so are an important aspect of a building’s aesthetics in patterns, textures and colors. Roof shingles, like other building materials on vernacular buildings, are typically of a material locally available. The type of shingle is taken into account before construction because the material affects the roof pitch and construction method: Some shingles can be installed on lath where others need solid sheathing (sheeting) on the roof deck. All shingle roofs are installed from the bottom upward beginning with a starter course and the edge seams offset to avoid leaks. Many shingle installations benefit from being placed on top of an underlayment material such as asphalt felt paper to prevent leaks even from wind driven rain and snow and ice dams in cold climates. At the ridge the shingles on one side of the roof simply extend past the ridge or there is a ridge cap consisting of boards, copper, or lead sheeting. An asphalt shingle roof has flexible asphalt shingles as the ridge cap. Some roof shingles are non-combustable or have a better fire rating than others which influence their use, some building codes do not allow the use of shingles with less than a class-A fire rating to be used on some types of buildings. Due to increased fire hazard, wood shingles and organic-based asphalt shingles have become less common than fiberglass-based asphalt shingles. No shingles are water-tight so the minimum recommended roof pitch is 4:12 without additional underlayment materials.
In the United States, fiberglass-based asphalt shingles are by far the most common roofing material used for residential roofing applications. In Europe they are called bitumen roof shingles or tile strips, and are much less common. They are easy to install, relatively affordable, last 20 to 50 years and are recyclable in some areas. Asphalt shingles come in a large number of styles and colors.
The protective nature of paper and fiberglass asphalt shingles primarily comes from the long-chain petroleum hydrocarbons, while wood shingles are protected by natural oils in the cellulose structure. Over time in the hot sun, these oils soften and when rain falls the oils are gradually washed out of the shingles. During rain, more water is channeled along eaves and complex rooflines, and these are subsequently more prone to erosion than other areas.
Eventually the loss of the oils causes asphalt shingle fibers to shrink and wood shingles to rot, exposing the nail heads under the shingles. Once the nail heads are exposed, water running down the roof can seep into the building around the nail shank, resulting in rotting of underlying roof building materials and causing moisture damage to ceilings and paint inside.
Heinola Rural Parish church, in Heinola, Finland. It was completed in 1755 and built most likely by August Sorsa. Close-up of the wooden shingle roof. The patterning is said to originate from Islamic architecture.
Two basic types of wood shingles are called shingles and shakes. The difference is in how they are made, the shingles are sawn and shakes are split. Wood shingles and shakes have long been known as a fire hazard and have been banned in various places, particularly in urban areas where exterior, combustible building materials contribute to devastating fires known as conflagrations.
The use of wooden roof shingles has existed in parts of the world with a long tradition of wooden buildings, especially Scandinavia, and Central and Eastern Europe. Nearly all the houses and buildings in colonial Chiloé were built with wood, and roof shingles were extensively employed in Chilota architecture.
Slate shingles are also called slate tiles, the usual name outside the US. Slate roof shingles are relatively expensive to install but can last 80 to 400 years depending on the quality of the slate used, and how well they are maintained. The material itself does not deteriorate, and may be recycled from one building to another.
The primary means of failure in a slate roof is when individual slates lose their peg attachment and begin to slide out of place. This can open up small gaps above each slate. A secondary mode of failure is when the slates themselves begin to break up. The lower parts of a slate may break loose, giving a gap below a slate. Commonly the small and stressed area above the nail hole may fail, allowing the slate to slip as before. In the worst cases, a slate may simply break in half and be lost altogether. A common repair to slate roofs is to apply ‘torching’, a mortar fillet underneath the slates, attaching them to the battens. This may applied as either a repair, to hold slipping slates, or pre-emptively on construction.
Where slates are particularly heavy, the roof may begin to split apart along the roof line. This usually follows rot developing and weakening the internal timbers, often as a result of poor ventilation within the roofspace. An important aspect to slate roofs is the use of a metal flashing which will last as long as the slates. Slate shingles may be cut in a variety of decorative patterns and are available in several colors.
Flagstone shingles are a traditional roofing material. Some stone shingles are fastened in place but some simply are held by gravity so the roof pitch cannot be too steep or the stones will slide off the roof. Sandstone has also been used to make shingles.
Metal Roofing Systems For Commercial and Residential
A metal roof is a roofing system made from metal pieces or tiles. It is a component of the building envelope.
Metal roofs can last up to 100 years, with installers providing 50 year warranties. Because of their longevity, most metal roofs are less expensive than asphalt shingles in the long term.
Metal roofing can consist of a high percentage of recycled material and is 100% recyclable. It does not get as hot as asphalt, a common roofing material, and it reflects heat away from the building underneath in summertime. On a larger scale, its use reduces the heat island effect of cities when compared to asphalt. Coupled with its better insulating abilities, metal roofs can offer not only a 40% reduction in energy costs in the summer, but also up to a 15% reduction in the energy costs in the winter according to a 2008 Study by Oak Ridge National Laboratory. This finding is based on the use of a strapping system of four inches between the plywood and “cool-color” metal on top, which provides an air gap between the plywood roof and the metal. Cool-color metals are light, reflective colors, like white. The study went on to say that re-sealing and insulating air ducts in the attic will save even more money.
Metal roofing is also lightweight, and can be installed on top of an existing roof. A lightweight roof is very useful for large and or old structures, as it helps to maintain the overall structural integrity of the building. Despite its light weight, metal roofing provides increased wind resistance when compared to other roofing materials. This is because metal roofing systems use interlocking panels.
Originally, metal roofs were made of corrugated galvanized steel: a wrought iron–steel sheet was coated with zinc and then roll-formed into corrugated sheets. Another approach is to blend zinc, aluminum, and silicon-coated steel. These products are sold under various trade names like “Zincalume” or “Galvalume”. The surface may display the raw zinc finish, or it may be used as a base metal under factory-coated colors. Another metal roofing product comes in a rolled form of various widths of so-called standing seam metal. The material is “seamed” together using a special seaming tool that is run vertically up the panel to seal the joints and prevent water intrusion.
Metal tile sheets can also be employed. These are usually painted or stone-coated steel. Stone coated steel roofing panels are made from zinc/aluminium-coated steel with an acrylic gel coating. The stones are usually a natural product with a colored ceramic coating. Stainless steel is another option. It is usually roll-formed into standing seam profiles for roofing; however, individual shingles are also available. Other metals used for roofing are lead, tin and aluminium and copper.
Copper is used for roofing because it offers corrosion resistance, durability, long life, low maintenance, radio frequency shielding, lightning protection, and sustainability benefits. Copper roofs are often one of the most architecturally distinguishable features of prominent buildings, including churches, government buildings, and universities. Today, copper is used in not only in roofing systems, but also for flashings and copings, rain gutters and downspouts, domes, spires, vaults, and various other architectural design elements. At the Lyle Center for Regenerative Studies in Pomona, California, copper was chosen for the roofing on regenerative principles: if the building were to be dismantled the copper could be reused because of its high value in recycling and its variety of potential uses. A vented copper roof assembly at Oak Ridge National Laboratories (U.S.) substantially reduced heat gain compared with stone-coated steel shingle (SR246E90) or asphalt shingle (SR093E89), resulting in lower energy costs.
Coating copper roof
Several different types of coatings are used on metal panels to prevent rust, provide waterproofing, or reflect heat. They are made of various materials such as epoxy and ceramic.
Ceramic coatings can be applied on metal roof materials to add heat-reflective properties. Most ceramic coatings are made from regular paint with ceramic beads mixed in as an additive.
Coatings are sometimes applied to copper. Clear coatings preserve the natural color, warmth, and metallic tone of copper alloys. Oils exclude moisture from copper roofs and flashings and simultaneously enhance their appearance by bringing out a rich luster and depth of color. The most popular oils are lemon oil, U.S.P., lemongrass oil, Native E.I., paraffin oils, linseed oil, and castor oil. On copper roofing or flashing, reapplication once every three years can effectively retard patina formation. In arid climates, the maximum span between oilings may be extended up to five years. Opaque paint coatings are primarily applied over copper when substrate integrity and longevity are desired but a specific color other than the naturally occurring copper hues is required. Lead-coated copper coatings are used when the appearance of exposed lead is desired or where water runoff from uncoated copper alloys would ordinarily stain lighter-colored building materials, such as marble, limestone, stucco, mortar, or concrete. Zinc-tin coatings are an alternative to lead coatings since they have approximately the same appearance and workability.