Top side venting of lightweight concrete in roof systems
An assembly and method for venting a flat or low sloped roof system eliminates the need for a base sheet membrane and fasteners and provides a spaced arrangement of V-grooves formed in the top surface of a new or existing lightweight concrete deck. The V-grooves allow moisture to migrate to the perimeter of the roof and exit the roof system. Instead of attaching a base sheet membrane to the lightweight concrete deck using penetrating fasteners, the roof membrane plies are attached directly to the primed lightweight concrete deck by self-adhesion, heat welding or with the use of cold adhesives. This prevents damage to the structural integrity of the underlying lightweight concrete, while providing an improved roof venting system.
This non-provisional patent application is based on provisional patent application Ser. No. 60/778,204 filed on Mar. 2, 2006. Applicant claims the benefit of the provisional patent application filing date under Title 35, United States Code section 119(e).
BACKGROUND OF THE INVENTION1. Field of the Invention
This invention relates to roofing systems, and, more particularly, to roofing systems that use lightweight insulating concrete with an overly inter-ply sheet and cap membrane on flat or low sloped roof areas.
2. Discussion of the Related Art
Generally, roof systems that use lightweight concrete with or without insulation require a base sheet membrane to be mechanically installed to the lightweight concrete for the purpose of allowing moisture to migrate. Once the base sheet is mechanically attached to the lightweight concrete, additional layers of roofing membrane are attached to the base sheet by either self adhesive, heat weld or cold adhesive. This bonds the membranes together to make up the roof assembly. Despite the widespread use of the mechanically attached base sheet membrane, used in flat and low sloped roof systems, there are significant drawbacks associated with its use. In particular, the increased amount of penetrating fasteners that need to be installed in order to meet the wind uplift requirements actually damage the lightweight the concrete at corners and along the perimeter of the roof. The resultant damage to the lightweight concrete, caused by the closely spaced fasteners, eventually leads to deck failure. Furthermore, when the roof needs to be replaced, requiring removal of the base sheet and fasteners, holes are left in the lightweight concrete. Thereafter, a new base sheet membrane is installed, and new fasteners penetrate additional areas of the existing lightweight concrete deck. Consequently, further damage is caused to the lightweight concrete deck.
It should be noted that the benefit of using lightweight concrete in lieu of insulation is not only to provide a slope for the roof system, but also to provide the owner with an insulating system that will remain intact after re-roofing and continue to provide the owner the slope and insulating value for all future roof systems.
In view of these shortcomings of the traditional mechanically attached base sheet membrane, there exists an urgent need in the roofing industry for an alternative venting system for new and existing lightweight concrete deck structures which overcomes the above described problems. More specifically, there is a need for a venting system that will allow moisture to travel to the perimeter of the roof, where the moisture can exit the roof assembly thru an A.R.B.S. (Alternative Roof Blocking System) of the type disclosed in U.S. Pat. No. 6,237,293 B1. Further, there is a need for venting the top side of a new or existing lightweight concrete deck which will considerably reduce costs for labor and material by eliminating the installation of the base sheet membrane and fasteners that are currently required for attachment to the lightweight concrete deck.
OBJECTS AND ADVANTAGES OF THE INVENTIONA primary object of the present invention is to eliminate the use of the mechanically attached base sheet currently used in flat or low sloped roof systems and to provide the new or existing lightweight concrete with V-grooves on the top surface which replace the function of the base sheet and allow the venting of moisture to travel to the roof perimeter and exit the roof system.
It is a further object of the present invention to provide necessary top side venting of a new or existing lightweight concrete roof deck without compromising the structural integrity of the lightweight system that is presently caused by installation of the base sheet membrane with mechanical fasteners that penetrate the lightweight concrete.
It is still a further object of the present invention to provide venting means in a low-sloped roof system which will release heat and moisture through an arrangement of V-grooves formed in the top side of a lightweight concrete deck.
SUMMARY OF THE INVENTIONThe present invention is directed to an improved roof venting system that eliminates the need of a base sheet membrane that is presently used and that is mechanically attached with fasteners to new or existing lightweight concrete. An improved venting system is achieved by installing an arrangement of V-grooves during the installation of new lightweight concrete. The V-grooves are approximately ½ inch to 1 inch deep and are spaced at approximately 3 to 12 inches apart. The V-grooves are installed during the finishing of the top coat using a 4 inch wide by 4 foot long aluminum flat bar having V-groove forming blades welded to bottom side of the tool. The V-groove blades are installed 3 inches on center, 6 inches on center or 12 inches on center, depending on the individual venting needs on new lightweight concrete. On existing lightweight concrete, the V-grooves are cut into the top surface of the lightweight concrete deck with a carbine blade. The V-grooves allow heat and moisture to migrate to the perimeter of the roof and out the vent holes of an A.R.B.S. (Alternative Roof Blocking System) of the type disclosed in U.S. Pat. No. 6,237,293 B1.
For a fuller understanding of the nature of the present invention, reference should be made to the detailed description taken in conjunction with the accompanying drawings in which:
Like reference numerals refer to like parts throughout the several views of the drawings.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTThe improved venting system of the present invention is used in conjunction with a low sloped or flat roof system of the type which uses lightweight insulating concrete. Referring to
Once the V-grooves 30 are formed in the top side 26, one or more layers of roof membrane 58 are attached to the top side of the lightweight insulating concrete deck. The one or more roof membrane plies 58 are attached to the top side 26 by self adhesion, heat welding or with the use of cold adhesives.
The V-grooves 30 allow heat and moisture to migrate (i.e., within the grooves 30) to the perimeter of the low sloped roof and to release out through vent holes of an A.R.B.S. (Alternative Roof Blocking System) 60, as seen in
While the present invention has been shown and described in accordance with preferred and practical embodiments thereof, it is recognized that departures from the instant disclosure are contemplated within the spirit and scope of the invention.
Claims
1. A roof system for installation on a roof structure of a building comprising:
- a lightweight insulating concrete deck applied on the roof structure, and said lightweight insulating concrete deck including a top surface;
- an arrangement of grooves formed in said top surface of said lightweight insulating concrete deck, and said grooves being structured and disposed for directing moisture and liquid to the perimeter of the roof structure; and
- at least one layer of roof membrane attached to said top surface of said lightweight insulating concrete deck.
2. The roof system as recited in claim 1 wherein said grooves are arranged in spaced, parallel relation on said top surface of said lightweight insulating concrete deck.
3. The roof system as recited in claim 1 wherein said grooves are at least 0.5 inch deep.
4. The roof system as recited in claim 1 wherein said grooves are between a 0.5 inch and 1.0 inch deep.
5. The roof system as recited in claim 1 wherein said grooves are arranged at spaced, parallel intervals of between 3 inches and 12 inches apart.
6. The roof system as recited in claim 1 wherein said at least one layer of roof membrane is attached directly to said top surface of said lightweight insulating concrete deck by self adhesion.
7. The roof system as recited in claim 1 wherein said at least one layer of roof membrane is attached directly to said top surface of said lightweight insulating concrete deck by heat welding.
8. The roof system as recited in claim 1 wherein said at least one layer of roof membrane is attached directly to said top surface of said lightweight insulating concrete deck by a cold adhesive.
9. The roof system as recited in claim 1 further comprising:
- a plurality of layers of roof membrane attached directly to said top surface of said lightweight insulating concrete deck.
10. A roof system for installation on a roof structure of a building comprising:
- a lightweight insulating concrete deck applied on the roof structure, and said lightweight insulating concrete deck including a top surface;
- an arrangement of grooves formed in said top surface of said lightweight insulating concrete deck, each of said grooves having a V-shaped cross-sectional configuration and said grooves being structured and disposed for directing heat and moisture to the perimeter of the roof structure; and
- at least one layer of roof membrane attached to said top surface of said lightweight insulating concrete deck.
11. The roof system as recited in claim 10 wherein said grooves are between 0.5 inch and 1.0 inch deep.
12. The roof system as recited in claim 10 wherein said grooves are arranged at spaced intervals of between 3 inches and 12 inches apart.
13. The roof system as recited in claim 10 wherein said at least one layer of roof membrane is attached directly to said top surface of said lightweight insulating concrete deck by self adhesion.
14. The roof system as recited-in claim 10 wherein said at least one layer of roof membrane is attached directly to said top surface of said lightweight insulating concrete deck by heat welding.
15. The roof system as recited in claim 10 wherein said at least one layer of roof membrane is attached directly to said top surface of said lightweight insulating concrete deck by a cold adhesive.
16. The roof system as recited in claim 10 further comprising:
- a plurality of layers of roof membrane attached directly to said top surface of said lightweight insulating concrete deck.
17. A method for venting a flat or low sloped roof system comprising the steps of:
- applying a lightweight insulating concrete deck to the top roof deck structure on a building;
- forming an arrangement of grooves in a top surface of said lightweight insulating concrete deck; and
- attaching at least one layer of roof membrane directly to said top surface of said lightweight insulating concrete deck.
18. The method as recited in claim 17 wherein said step of forming said arrangement of grooves in said top surface further comprises:
- moving a rake having a plurality of groove forming blades over said top surface of said lightweight insulating concrete deck during a finishing step of applying said lightweight insulating concrete deck to the top roof deck structure.
19. The method as recited in claim 17 wherein said step of forming said arrangement of grooves in said top surface further comprises the step of:
- cutting said arrangement of grooves with a rotary saw.
20. The method as recited in claim 17 wherein in each of the grooves in said arrangement of grooves has a V-shaped cross-sectional configuration and a depth ranging between 0.5 inch and 1.0 inch.
Type: Application
Filed: Feb 27, 2007
Publication Date: Sep 6, 2007
Inventor: Henry Gembala (Boca Raton, FL)
Application Number: 11/712,251
International Classification: E04F 17/00 (20060101); E04B 1/70 (20060101);