More Than Just A roofing Company
Need Metal Roof Repair Work on Your Commercial Building?
Origin Exteriors is a trusted commercial roofing contractor based in Lebanon and serving businesses throughout the Cincinnati and Dayon areas. Has your building suffered any storm damage this year? We are experts in metal roof repair work and the replacement of roofs of all types on commercial buildings like yours. If an inspection shows the damage is too extensive to allow for repairs, we can work with you to put a new roof on your building.
Full Service Exterior Contractor
We do a lot of metal roof repair work, as well as new commercial roof installation. But our team is highly trained and skilled at working on all aspects of the exterior of commercial buildings. If a storm has damaged your roof there is a good chance your gutter system has been compromised as well. We can inspect every inch of your gutters to be sure they are working properly before the next storm hits. The last thing you will want is gutters that are not functioning during heavy rains, allowing water to pool around the base of your building.
Commercial low sloped roofing systems have a variety of components that are used together to protect buildings against moisture, wind, fire, and heat transfer. There are different types of roof decks, vapor retarders, roof insulation, cover boards, attachment methods, and roofing membranes. It’s important to choose the right commercial roof system for your building so we will describe some of the components for your consideration.
THE ROOF DECK
A good low sloped roofing system begins with a dry, safe, and secure roof deck. The most common types found within commercial roof systems are wood, steel, and concrete.
- Wood roof decks consist of plywood, OSB, or wood planks. If any roof leaks have occurred for significant periods of time, deteriorated or damaged wood must be replaced when a new membrane roof system is installed.
- Steel decks are more common than wood decks and are also very durable. Steel decks can be attached to the framing with fasteners or it can be welded to the purlins.
- Structural concrete roof decks are also common in commercial and industrial buildings. It is important that the concrete is cured and dry before a new roof system is installed.
Vapor retarders are a good idea in cold climates such as Dayton and Cincinnati, especially when the interior of a building has relatively high levels of humidity. The laws of thermodynamics tell us that air pressure, heat, and moisture within our buildings attempt to equalize themselves. This means that air movement occurs in the following scenarios: hot air moves towards cold air and moist air moves to dry air. Air movement can be problematic within a roof assembly. If warm and moist air from the inside of a building is able to escape into a roof system, it will likely condense when it migrates all the way to the roof membrane during cold days.
Since the roof membrane itself is an excellent air retarder and it prevents moisture from entering (and exiting) the building, condensation will have a negative impact on the rest of the components within the roof system. Condensation will damage roof insulation such as polyisocyanurate as well as roof decks such as wood or steel. A vapor retarder placed beneath the warm side of the insulation will prevent moist air from entering the roofing system and is an excellent roof system component to prevent damage caused by condensation. Common types of vapor retarders include polyethylene and polymer modified bitumen.
Roof insulation is typically installed above the roof deck on most membrane systems and the most common products used are rigid foam insulation boards. Most building codes in the Cincinnati area require the roof system to have a minimum R-value of 25. Common types of rigid foam insulation are expanded polystyrene or EPS, extruded polystyrene or XPS, and polyisocyanurate.
The most widely used commercial and industrial roof insulation board today is polyisocyanurate. According to several polyisocyanurate manufacturers, the long-term thermal resistance (LTTR) of polyisocyanurate is R-5.7 per inch. When a new roof is installed and polyisocyanurate is used, approximately 4.5 inches of insulation is required to reach R-25.
To avoid thermal voids or gaps in the rigid insulation boards, a minimum of 2 layers of insulation should be installed with the seams staggered. If the roof deck is structurally sloped towards the roof drains or gutters, insulation with consistent board thickness can be installed. However, when the roof deck is flat or water needs to be diverted to roof drains or gutters, a tapered insulation system can be designed to ensure the roof has enough slope to provide positive drainage.
Cover boards are beneficial to a roof system in a number of different ways. They can provide fire protection, additional R-value, add compression strength, and provide impact resistance. Cover boards protect a roof system from foot traffic, other trades, and hail. They can also deliver greater wind uplift resistance and hide imperfections in the rigid insulation boards. Common types of cover boards that can be found on a roof system include perlite, gypsum, fiberglass, HD polyiso, and wood fiber.
The products in roof assembly can be attached in a number of different ways. The four most common attachment methods in commercial roof systems are adhered, ballasted, mechanically attached, and electromagnetic induction welded.
- Adhered systems perform better than any other roof system. The membrane can adhere directly to the roof insulation or a cover board.
- Mechanically attached membranes are loose-laid and then fastened through the roof insulation to the roof deck. The fastening pattern is determined by the manufacturer and occurs in a linear fashion.
- Ballasted roofs contain a loose laid membrane with at least 10 pounds per square foot of ballast (depending on the wind load) to hold the system in place. Ballast can consist of aggregate or paver systems.
- Electromagnetic induction welding is common for TPO and PVC roof membranes. The single-ply membrane is welded to special plates that are attached to the insulation with an induction tool. This system is commonly referred to as RhinoBond or InvsiWeld.
The most common roof coverings for low-sloped commercial and industrial roofs are BUR, modified bitumen, and single-ply membranes. The three most popular types of single-ply membranes are TPO, EPDM, and PVC.
- BUR or Built-up Roofs are typically applied with several plies of felt and asphalt. The asphalt is coated with an aggregate, cap sheet, or coating to protect the asphalt from UV degradation.
- Modified bitumen roof systems are also asphalt based but polymers are added to enhance performance and make the roof easier to install.
- TPO roof systems (thermoplastic polyolefin) make up the largest market share (by square footage under warranty) in the U.S. The membrane seams and flashings remain watertight as they are hot air welded.
- EPDM is a rubber membrane that has been a high performing roof system since the 1970s. The membrane is an excellent choice for cold-weather climates.
- PVC roof systems (polyvinyl chloride) have hot air welded seams similar to TPO roofs. Unlike EPDM, PVC is resistant to oils and grease which makes it an excellent choice for restaurants and other industrial applications.
Call us Today
Calling Origin Exteriors is the only call you will need to make for work around the exterior of your home or business. With experience in replacing siding, installing new gutters, metal roof repair work and roof replacement, we truly are a one-stop shop. Are you having a big event or sale at your business? Let us come power wash the exterior of your property to give it a nice clean look. Call today to schedule an inspection, or to get a free quote on any of our services. (513) 549-2123 .