Patent Application
20180112411
The present disclosure relates to retrofit roofing systems that are installed over existing metal roofs. More particularly, the present disclosure relates to the structure and installation of the support frame that supports the retrofit roof above the existing roof.
Metal roof decking is a building envelope system made from metal decking panels or sections. Each metal decking panel is secured by fasteners to the support structure (typically made of steel) of the building on which the roof is located. Metal roof decking is inherently strong and lightweight, and thus offers several advantages over other types of roofing (i.e., asphalt shingles, etc.), such as increased durability, energy efficiency, resistance to weather damage, and ease of installation, as well as being comparatively economical and having low maintenance requirements. Also, metal roof decking may be designed for use with pitched, flat, or arched construction, and may be applied to nearly all types of buildings.
Standing seam metal roofs are also popular on virtually all types of buildings due to their weather-tightness, durability, and flexible design. Additionally, standing seam metal roofs are more energy efficient and cost effective than many non-metal counterparts, and have an additional desired characteristic of allowing for thermal movement within the roof system.
Metal roof decking products have a number of shapes, materials, and aesthetic variations that can be used in constructing roof decking for buildings. One common type of metal roof decking is known as a fluted, or ribbed, roof decking. Ribbed metal roof decking includes a plurality of ribbed metal roof decking panels, each panel characterized by a sequence of alternating upper and lower surfaces that extend the length of the panel. The upper surfaces, or ribs, are found substantially in an upper plane, and are substantially parallel to each other. Likewise, the lower surfaces, or valleys, are found substantially in a lower plane, one that is generally parallel to and spaced vertically apart from the upper plane. The upper and lower surfaces are connected by a series of vertical or sloped walls which also extend the length of the panel. The upper, lower and vertical or sloped walls define flutes, or channels. When installed to form metal roof decking, the ribbed metal roof decking panels typically overlap one another, and span over and are secured by fasteners to underlying support structures, sometimes referred to as purlins. In this configuration, the ribbed metal roof decking panels are connected to form a continuous span to create the roof envelope of a building.
For various reasons, the metal roof decking of a building, in part or whole, may be in need of repair, replacement, upgrade, or a general retrofit. Due to the lightweight qualities of some metal roof decking, an existing roof may be retrofit by installing a system of subframes over the original roof decking, and securing the new roof decking to the subframe system. The use of subframe systems in this manner provides additional support and points of attachment for the new metal roof decking panels. In some instances, however, conventional subframe systems cannot be used to transition from an older roof configuration in need of retrofit to a new metal roof decking that complies with new construction practices and roof uplift requirements. Additionally, conventional subframe systems may not provide the necessary strength over a long roof span, and may require inefficient production and time-consuming installation processes.
Two subframe configurations from U.S. Pat. No. 7,861,480 are identified generally by reference numeral 100 in PRIOR ART
First and second walls 106, 108 are coupled to and interconnected by base 107. As shown, base 107 is the lowermost portion of subframe 100 and extends horizontally between respective ends of first and second walls 106, 108. A channel is formed by first wall 106, base 107, and second wall 108. A void, or punch out 109, is created in subframe 100. Punch out 109 extends along a central axis “C” that is generally perpendicular to the longitudinal axis “L” of subframe 100. Punch out 109 passes through corresponding sections of first wall 106, second wall 108, and base 107. When subframe 100 is installed over an existing roof panel, punch out 109 is configured to matingly receive or fit over a rib 230 of the existing roof panel. In the embodiment shown in
To couple subframe 100 to the existing roof system 200, subframe 100 is positioned over a section 220 in alignment with a purlin support 210 such that longitudinal flanges 102, 104 extend generally perpendicular to the direction of ribs 230 of existing roof system 200. When aligned with purlin support 210, base 107 of subframe 100 rests on valley 240 of existing roof section 220 with punch out 109 positioned over a rib 230, Fasteners 300 are then inserted through base 107 and valley 240 and into purlin support 210 at intervals along the length of subframe 100 to couple subframe 100 to top flange 212 of purlin support 210. In some embodiments, the respective heights of subframe 100 and ribs 230 may be chosen such that first and second lips 103, 105 extend so as to rest in contact with an upper surface of ribs 230, as shown in
Subframe 100 may be created by a roll formed manufacturing process. With this process, the length of subframe 100 can easily be controlled and tailored to the desired span of existing metal roof decking to be retrofit. Moreover, with roll formed manufacturing, any length of subframe 100 is obtainable, allowing subframe 100 to be used on any span of existing roof decking.
The disclosure provides a subframe configuration for a retrofit roof wherein the subframe is connected to the upper surface of the rib and to the valley/purlin of the existing roof. The connection can be a mechanical interference connection or one that is formed by a mechanical connector.
The subframe of the disclosure includes a rib flange that extends from the bottom of the lip. The rib flange is disposed substantially parallel to the base of the subframe. When installed, a connector extends through the rib flange into a rib of the existing roof. Rib flange can be continuous or provided only at each or just some of the ribs.
In one configuration, the subframe includes a base that is secured to the purlin through the metal roof deck sections. The base can define openings for the connectors. A wall extends up from the base. The height of the wall is at least the height of the rib but is typically higher to provide space to receive insulation. These can be up to twenty-four inches tall. A longitudinal flange extends from the top of the wall and is substantially parallel to the base. A lip extends down from the outer edge of the flange with the rib flange extending from the bottom of the lip.
An advantage of the rib flange is that the height of the wall can be increased to provide room for insulation.
This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This summary is not intended to identify key features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.
Similar numbers refer to similar parts throughout the specification.
The exemplary subframe of the disclosure is indicated generally by the reference number 2 in
Subframe 2 includes base 7 that is secured to purlin flange 212 through roof 220 with a fastener such as a screw or bolt. Wall 8 extends up substantially vertically from base 7 and can extend up from an edge of base 7. Wall 8 can also extend at a non-vertical angle. In either configuration, wall 8 taller than rib 230. Wall 8 also may extend substantially above the top of rib 230 to provide space for insulation. For example, wall 8 can be six, nine, twelve, fifteen, twenty or twenty four inches tall with rib 230 being one to three inches.
A top flange 4 extends from the top of wall 8. In the exemplary configuration, top flange 4 extends in a direction opposite to base 7 to define an “S” shape in cross section. In another configuration, flange 4 can extend in the same direction as base 7 to define a “C” shape in cross section.
Lip 5 extends down from the outer edge of flange 4 to engage the top of rib 230. Lip 5 can be vertical or disposed at a non-vertical angle.
In the configuration of subframe 2 depicted in
A rib flange 10 extends outwardly from the lower edge of lip 5. Rib flange 10 is substantially parallel to base 7. Rib flange 10 can be continuous as shown in
Subframe 2 is thus connected to the existing roof with a pair of spaced connections which allows subframe 2 to resist lateral forces and torque forces. A retrofit roof 400 is connected to the subframes 2
In the foregoing description, certain terms have been used for brevity, clearness, and understanding. No unnecessary limitations are to be implied therefrom beyond the requirement of the prior art because such terms are used for descriptive purposes and are intended to be broadly construed. Moreover, the descriptions and illustrations of the exemplary configurations are examples and the claimed invention is not limited to the exact details shown or described. Throughout the description and claims of this specification the words “comprise” and “include” as well as variations of those words, such as “comprises,” “includes,” “comprising,” and “including” are not intended to exclude additives, components, integers, or steps.
This application claims the benefit of U.S. Provisional Patent Application Ser. No. 62/412,924 filed Oct. 26, 2016; the disclosures of which are incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| 62412924 | Oct 2016 | US |
