Vented Radiant Barriers

Abstract

Structural ventilated radiant barrier roofing panels are disclosed. The radiant barrier roofing panels have panel with a first side formed with a plurality of channels and covered with a perforated radiant barrier to form a flow path. When installed on a structure, the radiant barrier roofing panels form a flow path from inside the attic, through the perforations, through the channels, and through abutment spaces between adjacent panels to allow for ventilation of the attic. Methods of ventilating an attic of a structure using radiant barrier roofing panels and of manufacturing radiant barrier roofing panels are also disclosed.

Description

TECHNICAL FIELD

This application is directed, in general, to residential construction, and more specifically, to vented radiant barriers for structural roof decking.

BACKGROUND

The following discussion of the background is intended to facilitate an understanding of the present disclosure only. It should be appreciated that the discussion is not an acknowledgement or admission that any of the material referred to was part of the common general knowledge at the priority date of the application.

Radiant barriers have been used in housing for many decades. The low emissivity barriers reduce radiant heat transfer from the underside of heated roofing materials to other aspects of the attic of a house. The radiant barriers reduce the cooling load of the house. While radiant barriers have been used, improvements remain desirable.

SUMMARY

According to an illustrative embodiment a radiant barrier roofing panel includes a panel having a first and a second side. The panel is formed with a plurality of channels on the first side of the panel. The radiant barrier roofing panel further includes a radiant barrier having a foil layer and may have a carrier layer. The foil layer has a first side and a second side, and the carrier layer has a first side and a second side. The second side of the foil layer is coupled to the first side of the carrier layer. The second side of the carrier layer of the radiant barrier is coupled to the first side of the panel, and the radiant barrier extends across the plurality of channels to form ventilation pathways. The radiant barrier is perforated at least over the plurality of channels. In some embodiments, the carrier may be omitted.

According to an illustrative embodiment, a method for ventilating an attic includes the steps of attaching a plurality of radiant barrier roofing panels to a plurality of rafters of an attic, wherein each of the plurality of radiant barrier roofing panels include a panel having a first and a second side. The panel is formed with a plurality of channels on the first side of the panel. The radiant barrier roofing panel further includes a radiant barrier having a foil layer and an optional carrier layer. The foil layer has a first side and a second side, and the carrier layer has a first side and a second side. The second side of the foil layer is coupled to the first side of the carrier layer. The second side of the carrier layer of the radiant barrier is coupled to the first side of the panel, and the radiant barrier extends across the plurality of channels to form ventilation pathways. The radiant barrier is perforated at least over the plurality of channels.

The method further includes installing roofing material over the second side of each of the plurality of radiant barrier panels. The plurality of radiant barrier roofing panels is installed with the radiant barrier facing the attic. At least two radiant barrier panels are installed adjacent to each other on the same rafter with an abutment gap between the two adjacent radiant barrier panels. For at least one radiant barrier panel, at least one perforation of the radiant barrier and at least one of the plurality of channels are in fluid communication with each other and the at least one of the plurality of channels is in fluid communication with the abutment gap, to form a flow path for vapors to travel from the attic to the second side of the panels.

According to an illustrative embodiment a method of applying a radiant barrier to a roof of a house includes coupling radiant barrier roofing panels, as described herein, to a plurality of rafters with a plurality of channels substantially in a panel of the radiant roofing barrier panel being perpendicular to the plurality of rafters and wherein ends of the plurality of the radiant barrier roofing panels have an abutment gap sufficient to allow venting from ends of at least some of the plurality of radiant barrier roofing panels.

According to an illustrative embodiment, a vented radiant barrier roofing panel includes a panel formed with a plurality of channels on one side running along a dimension of the panel and having a thickness of at least 0.25 inches. The vented radiant barrier roofing panel further includes a radiant barrier coupled over the plurality of channels of the panel to form a plurality of ventilation pathways. At least a portion the radiant barrier is perforated over the plurality of channels to provide fluid transfer through the plurality of channels.

Other embodiments and methods are disclosed herein.

DESCRIPTION OF THE DRAWINGS

Illustrative embodiments of the present invention are described in detail below with reference to the attached drawing figures, which are incorporated by reference herein and wherein:

FIG. 1A is a schematic elevation view of a house having a radiant barrier roofing panel according to an illustrative embodiment;

FIG. 1B is a detailed, cross-sectional view of a portion of the radiant barrier roofing panel of FIG. 1A;

FIG. 2 is a schematic, perspective view of a portion of a radiant barrier roofing panel shown in an assembled position according to an illustrative embodiment;

FIG. 3 is a schematic elevation end view of a portion of a radiant barrier roofing panel;

FIG. 4 is a schematic, perspective view of an attic of a house having radiant barrier roofing panels in an installed position according to an illustrative embodiment; and

FIG. 5 is a schematic cross-sectional view of an illustrative embodiment of radiant barrier roofing panels on a rafter of a house.

DETAILED DESCRIPTION

In the following detailed description of the preferred embodiments, reference is made to the accompanying drawings that form a part hereof, and in which is shown, by way of illustration, specific embodiments in which the invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention, and it is understood that other embodiments may be utilized and that logical structural, mechanical, electrical, and chemical changes may be made without departing from the spirit or scope of the invention. To avoid detail not necessary to enable those skilled in the art to practice the invention, the description may omit certain information known to those skilled in the art. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is defined only by the claims.

Unless otherwise indicated, as used throughout this document, “or” does not require mutual exclusivity.

One of the perceived issues with the application of radiant barriers in the residential housing market has to do with the possibility of condensation forming during seasonal changes. As a safeguard it is desirable to have any vapors or volatile organic compounds (VOCs) in the attic find a way to be released before condensation forms. According to an aspect of the present invention, a radiant barrier roofing panel is vented. A radiant barrier roofing panel is provided that includes channels that form ventilation pathways to help remove any such vapor or VOCs as will be described in more detail below.

Referring now to the figures and initially to FIG. 1, a radiant barrier roofing panel 100 is shown in hidden lines installed on a house 104 in FIG. 1A, and a detailed cross section of the portion of the radiant barrier roofing panel 100 is shown in FIG. 1B. In FIG. 1 B, the radiant barrier roofing panel 100 is shown with underlayment 108, such a felt or roofing paper, with shingles 112 thereon.

Referring now primarily to FIGS. 1B and 2, the radiant barrier roofing panel 100 includes a panel 116 having a first side 120 and a second side 124. As used herein designation of a first side and a second side is arbitrary and is provided for orientation as shown in the figures. In an installed position (shown in FIG. 1A and FIG. 1B), the first side 120 faces outward (i.e., toward sky) and the second side 124 faces towards an attic space (168 in FIG. 4) of the house 104. The panel 116 is formed with a plurality of channels 128 on the second side 124 of the panel 116 and running a length of the panel 116. In the installed position, the plurality of channels 128 are perpendicular to a plurality of rafters (172 in FIG. 4).

A foil layer 132, or a laminate, is coupled to the second side 124 of the panel 116 and extends across the plurality of channels 128 to form ventilation pathways 136. The foil layer 132 (and carrier 144—see FIG. 3) is perforated with perforations 138 at least at the channels 128 as shown in FIG. 2. In some embodiments, the foil layer 132 is perforated all over. As used herein “foil” may be a very thin sheet of metal, e.g., aluminum foil, that resists moisture content. In another embodiment, a “foil” can be any thin material that can cover the channel and not readily condensate or deteriorate, e.g., paper film. In some embodiments, the foil may be omitted, and the channels remain open; the open channels still remove VOCs but do not direct the fluid flow in the same manner. An aluminum foil is used in some embodiment to provide low E value for energy savings and to enhance the fire rating of the panel.

Referring now primarily to FIG. 3, a schematic end view of a portion the radiant barrier roofing panel 100 showing one member of the plurality of channels 128 is presented. In this view, one may see the foil layer 132 is coupled to a carrier 144. In one embodiment the carrier 144 is kraft paper. The carrier 144 however may be any suitable material that provides structural support for the foil layer 132. In some embodiments, the carrier 144 is a scrim fiber mesh. Those skilled in the art will appreciate that other materials may be used or no carrier material. The foil layer 132 and carrier 144 together form a radiant barrier 148. The radiant barrier 148 is coupled to the second side 124 of the panel 116 using an adhesive 152, such as a polyvinyl acetate (PVA) glue or other non-carcinogenic water based adhesive binder. In some embodiments, the radiant barrier 148 comprises only the foil layer.

The channel 128 has a depth 156 and a width of 160. In some embodiments, the depth 156 is as deep as possible while maintaining United States Department of Commerce Performance Standard-2 structural integrity of the panel 116 in terms of the span strength. The depth 156 of the channels 128 should not be so large that the structural integrity of the panel 116 is reduced to less than that needed for a structural roofing panel. In some embodiments, the depth 156 of the channels 128 is in the range of 30-55% of a thickness 164 of the panel 116, and in some embodiments is in the range of 35-45%. The thickness 164 of the panel 116 may be in the range of 1.5″ to 0.25″. In some embodiments, the thickness 164 of the panel 116 is in the range of 1.0″ to 0.375″. In some embodiments the thickness 164 of the panel 116 is about 0.75″. The channel 128 runs the longitudinal length of the panel 116, with each of the channels 128 being substantially parallel to each other as shown clearly in FIG. 2.

In other embodiments, the channels 128 may be formed in patterns other than running the longitudinal length of the panel 116 with the channels 128 substantially parallel to each other. For example, some or all of the channels 128 may run diagonally across the panel 116 or orthogonal to the longitudinal length of the panel 116. In addition, some channels 128 may not span the entire length or width of the panel 116. In addition, some channels 128 may bisect other channels 128 to create flow paths between bisecting channels 128.

The base for the panel 116 may be a United States Department of Commerce Performance Standard-2 structural wood-based panel 140, such veneered plywood, orientated strand board or other cross laminated structural wood panels.

Referring now primarily to FIGS. 3 and 4, and initially to FIG. 4, a portion of a house 104 is presented showing an interior of a portion of an attic 168. In this view, one may see a plurality of rafters 172. A plurality of the radiant barrier roofing panels 100 are coupled to the rafters 172. Shingles 112 (FIG. 1B) are placed on the first side 120 of the radiant barrier roofing panels 100 and the foil layer 132 faces the attic 168. A person skilled in the art will appreciate that other roofing materials may also be used to cover the radiant barrier roofing panels 100, such as underlayment materials, such as felt or tar paper underlayment, and other common roofing materials, such as tiles, shakes, metal roofing, wood, slate, PVC or synthetic materials, etc.

Referring now primarily to FIG. 5, a cross sectional view showing two radiant barrier roofing panels 100 meeting on a first side 176 of a rafter 172 is shown. A first radiant barrier roofing panel 184 has a first end 188 and second end 192. A second radiant barrier roofing panel 196 has a first end 200 and a second end 204. The second end 192 of the first radiant barrier roofing panel 184 is supported on the first side 176 of the rafter 172, and the first end 200 of the second radiant barrier roofing panel 196 rests on the same rafter 172 with an abutment gap 208 formed between the second end 192 and the first end 200. The ventilation pathways 136 from each of the radiant barrier roofing panels 184, 196 may line up or may not line up.

The abutment gap 208 may take different dimensions but is usually in the range of 0.5 to 0.3 inches and in one embodiment is a minimum ⅛ of an inch. The abutment gap 208 provides a flow path 212 for any gasses being carried by the ventilation pathways 136 to exit from the attic 168 by going from there through the assorted openings and flow paths through the natural air flow provided at the bottom laps of underlayment 108 and the shingles 112.

With references generally to FIGS. 1-5, when installed, any vapors or VOCs present in the attic space 168, or attic, that might otherwise cause condensation or other issues may enter the through the perforations 138 and flow horizontally (relative to gravity field) through the ventilation pathways 136 formed by the channels 128 and radiant barrier 148 to an edge at a rafter 172 and then by flow path 212 (FIG. 5) of the abutment gap 208 through the assorted openings and flow paths through the natural air flow provided at the bottom laps of underlayment 108 and the shingles 112. In this way, vapor is avoided in the attic 168 or at least additional confidence gained that condensation is less likely to form inside the building envelope

To manufacture the radiant barrier roofing panel 100 according to one illustrative embodiment, the panel 116, e.g., an OSB or plywood, is formed in the usual way as those skilled in the art will appreciate and then channels 128 are formed. In one embodiment, the channels 128 are formed using a specialty saw, which is like an industrial sized router, that cuts the grooves or channels 128. Other means known in the art to form channels 128 may be used. The depth 156 (FIG. 3) of the channel 128 is small enough that the depth 156 does not negatively impact the structural integrity the panel 116. In one embodiment in which the panel 116 is plywood the depth 156 of the channel 128 is 50% of the thickness 164 of the panel 116. In one illustrative embodiment in which the panel 116 is OSB with a thickness of 7/16″ (0.438″), a channel depth 156 of 19/32″ reaches into the center layer of the panel while maintaining the panel's span rating. In some embodiments, the depth 156 is just sized to keep Dept. of Commerce PS2 qualification span rating (dimension between rafters 172). Those skilled in the art will appreciate that other dimension may be used.

After the channels 128 are formed, the adhesive 152 (FIG. 3), or glue, is applied to the second side 124 of the panel 116. In some embodiments, the adhesive is omitted from the channels 128. Then, the radiant barrier 148 (e.g., foil 132 and carrier 144) is applied to the adhesive 152. In some embodiments, the adhesive 152 may be applied to the surface of the radiant barrier 148, namely the carrier 144, and then the radiant barrier 148 applied onto the second side of the panel 116. In other embodiments, the radiant barrier 148 may be formed in the process of forming the radiant barrier roofing panel 100 by adhering the carrier 144 to the panel 116 and then adhering the foil layer 132 to the carrier 144. If the radiant barrier 148 is formed in the process of forming the radiant barrier roofing panel 100 or the radiant barrier 148 is not pre-perforated, the radiant barrier 148 is then perforated at least at the locations where the radiant barrier 148 covers the channels 128.

According to an illustrative embodiment, a method of applying a radiant barrier to a roof of a house includes coupling radiant barrier roofing panels of the type described herein to a plurality of rafters with the plurality of channels perpendicular to the plurality of rafters and wherein ends of the plurality of panels have an abutment space, or gap (e.g., 208 in FIG. 5), sufficient to allowing venting from the ends of at least some of the plurality of panels.

According to an illustrative embodiment a method of ventilating an attic of a structure includes the steps of attaching a plurality of radiant barrier roofing panels of the type described herein to a plurality of rafters of an attic with the foil layer facing the attic, wherein an end of at least some of the radiant barrier roofing panels overlap a rafter of the attic. By this manner multiple radiant barrier roofing panels are installed over the span of the attic and adjacent ends of different radiant barrier roofing panels are located on the same rafter. When installed, the radiant barrier energy panels are spaced on the rafter to leave an abutment space or group, which defines a flow path between the edges adjacent radiant barrier roofing panels. The method may further include the step of covering the exterior side of the radiant barrier roofing panels with appropriate roofing material such as an underlayment or roofing shingles.

By installing the radiant barrier roofing panels in this or an analogous manner, a flow path is created for ventilation of the attic. Since the foil layer of the radiant barrier roofing panel is in contact with the atmosphere within the attic, vapors present in within the attic may flow first through the perforations of the radiant barrier and into the channels. Vapor within the channels may then flow through the channels to the ends of the radiant barrier roofing panels at which point the vapor flows into the abutment space or gap. Thereby, resulting in the ventilation of vapors from inside of the attic to the exterior side of the radiant barrier roofing panels. In the method that includes the step of covering the exterior side of the radiant barrier roofing panels with appropriate roofing material, the vapors are further ventilated to the exterior of the structure by a flow path under and between the components of the appropriate roofing material, for example, through openings between adjacent shingles applied to the radiant barrier roofing panels.

In some illustrative embodiments, the radiant barrier roofing panel 100 may help with ventilation when under-sheathing insulation is used. When installing foam plastic under-sheathing insulation, an illustrative radiant barrier roofing panel 100 is particularly useful since the radiant barrier roofing panel 100 includes vents or channels cut into the panel covered by the perforated radiant barrier. When the under sheathing open cell foam is placed proximate the attic-facing surface of the perforated radiant barrier 148, the perforations and channels allow moisture and volatile organic compounds to vent to the outside of the building envelope.

In some embodiments, the radiant barrier roofing panel 100 may be helpful with fire characteristics of the assembly. For example, where foam plastic components will be required to undergo flame and smoke testing methods, the radiant barrier roofing panels 100 may assist with the fire rating by increasing the fire rating of an assembly by including the radiant barrier roofing panel 100 in that assembly. As another aspect, venting the moisture content created in the building's envelope may improve human health and increase the life expectancy of the building's mechanicals systems. This is particularly the case in structures using foam plastics under sheathing because the mechanical systems of the building bare the total responsibility of venting moisture and other VOCs from the building envelope.

There are many examples of embodiment of the disclosure. Some examples follow.

Example 1. A radiant barrier roofing panel comprising:

• • a panel having a first and a second side, wherein in an installed position the second side of the panel faces an attic of a house;
  • wherein the panel is formed with a plurality of channels on the second side of the panel, wherein in the installed position the plurality of channels is perpendicular to a plurality of rafters; and
  • a foil layer coupled to the second side of the panel and extending across the plurality of channels to form ventilation pathways and wherein the foil layer is perforated at least over the plurality of channels in an assembled position.

Example 2. The radiant barrier roofing panel of Example 1, wherein the panels comprise structural wood-based panels.

Example 3. The radiant barrier roofing panel of Example 2, wherein the structural wood-based panel is plywood or OSB.

Example 4. The radiant barrier roofing panel of Examples 2 or 3, wherein the plurality of channels each have a depth in the ranges of 30-50% of a thickness of the panel.

Example 5. The radiant barrier roofing panel of Examples 2, 3, or 4, wherein the perforated foil layer is coupled to the second side of the panel by PVA glue.

Example 6. A method of applying a radiant barrier to a roof of a house, comprising coupling radiant barrier roofing panels of Example 1 to a plurality of rafters with the plurality of channels perpendicular to the plurality of rafters and wherein ends of the plurality of panels have an abutment space, or gap, sufficient to allowing venting from ends of at least some of the plurality of panels.

Although the present invention and its advantages have been disclosed in the context of certain illustrative, non-limiting embodiments, it should be understood that various changes, substitutions, permutations, and alterations can be made without departing from the scope of the invention as defined by the claims. It will be appreciated that any feature that is described in a connection to any one embodiment may also be applicable to any other embodiment.

Claims

1. A radiant barrier roofing panel comprising: a panel having a first and a second side, wherein the panel is formed with a plurality of channels on the first side of the panel;a radiant barrier comprising a foil layer, wherein the foil layer has a first side and a second side;wherein the second side of the foil layer of the radiant barrier is coupled to the first side of the panel and the radiant barrier extends across the plurality of channels to form ventilation pathways; andwherein the radiant barrier is perforated at least over the plurality of channels.

2. The radiant barrier roofing panel of claim 1, wherein the radiant barrier comprises the foil layer and a carrier layer;the carrier layer has a first side and a second side;the second side of the foil layer is coupled to the first side of the carrier layer; andthe second side of the foil layer of the radiant barrier is coupled to the first side of the panel.

3. The radiant barrier roofing panel of claim 1, wherein in an installed position the first side of the foil layer faces an attic of a house, and the second side of the panel faces a shingle layer of a roof of the house.

4. The radiant barrier roofing panel of claim 1, wherein the plurality of channels is formed along a longitudinal length of the panel and the plurality of channels are substantially parallel to each other.

5. The radiant barrier roofing panel of claim 1, wherein the panel comprises a structural wood-based panel.

6. The radiant barrier roofing panel of claim 5, wherein the structural wood-based panel is plywood or oriented strand board.

7. The radiant barrier roofing panel of claim 1, wherein at least one of the plurality of channels has a depth in the range of 30-50% of a thickness of the panel.

8. The radiant barrier roofing panel of claim 7, wherein the thickness of the panel is in the range of 1.0-0.375 inches.

9. The radiant barrier roofing panel of claim 1, wherein in an installed position the first side of the foil layer faces an attic of a house and the second side of the panel faces a shingle layer of a roof of the house;wherein each of channels of the plurality of channels is formed along a longitudinal length of the panel and each of the channels of the plurality of channels are substantially parallel to each other;wherein the panel is plywood or oriented strand board;wherein at least one of the plurality of channels has a depth in the range of 30-50% of a thickness of the panel; andwherein the thickness of the panel is in the range of 1.0-0.375 inches.

10. A method for ventilating an attic comprising the steps of: attaching a plurality of radiant barrier roofing panels to a plurality of rafters of an attic, wherein each of the plurality of radiant barrier roofing panels comprise:a panel having a first and a second side, wherein the panel is formed with a plurality of channels on the first side of the panel,a radiant barrier comprising a foil layer and a carrier layer, wherein the foil layer has a first side and a second side and the carrier layer has a first side and a second side, wherein the second side of the foil layer is coupled to the first side of the carrier layer,wherein the second side of the carrier layer of the radiant barrier is coupled to the first side of the panel and the radiant barrier extends across the plurality of channels to form ventilation pathways, andwherein the radiant barrier is perforated at least over the plurality of channels; andinstalling roofing material over the second side of each of the plurality of radiant barrier panels;wherein the plurality of radiant barrier roofing panels is installed with the radiant barrier facing the attic;wherein at least two radiant barrier panels are installed adjacent to each other on the same rafter with an abutment gap between the two adjacent radiant barrier panels;wherein for at least one radiant barrier panel at least one perforation of the radiant barrier and at least one of the plurality of channels are in fluid communication with each other and the at least one of the plurality of channels is in fluid communication with the abutment gap, to form a flow path for vapors to travel from the attic to the second side of the panels.

11. The method of claim 10, wherein the plurality of channels are formed along a longitudinal length of the panel and the plurality of channels are substantially parallel to each other.

12. The method of claim 10, wherein, when the radiant barrier roofing panel is in the installed position, the plurality of channels are perpendicular to a plurality of rafters.

13. The method of claim 10, wherein the panel comprises a structural wood-based panel.

14. The method of claim 13, wherein the structural wood-based panel is plywood or oriented strand board.

15. The method of claim 10, wherein at least one of the plurality of channels has a depth in the range of 30-50% of a thickness of the panel.

16. The method of claim 15, wherein the thickness of the panel is in the range of 1.0-0.375 inches.

17. The method of claim 10, wherein the plurality of channels are formed along a longitudinal length of the panel and the plurality of channels are substantially parallel to each other;wherein, when the radiant barrier roofing panel is in the installed position, the plurality of channels is substantially perpendicular to a plurality of rafters;wherein the panel is plywood or oriented strand board;wherein at least one of the plurality of channels has a depth in the range of 30-50% of a thickness of the panel; andwherein the thickness of the panel is in the range of 1.0-0.375 inches.

18. A vented radiant barrier roofing panel comprising: a panel formed with a plurality of channels on one side running along a dimension of the panel and having a thickness of at least 0.25 inches;a radiant barrier coupled over the plurality of channels of the panel to form a plurality of ventilation pathways; andwherein at least a portion the radiant barrier is perforated over the plurality of channels to provide fluid transfer through the plurality of channels.

19. The vented radiant barrier roofing panel of claim 18, wherein the radiant barrier comprises a foil layer and a carrier layer coupled to each other.