Flush mounted self-flashing dual pane skylight

A self flashing dual pane skylight for flush mounting on a roof having an inclined slope is disclosed. The skylight is preferably rectangular and is made up of upper and lower light transmitting panes having two mutually opposed side edges and opposed top and bottom edges. The upper pane preferably contains a convexly curved dome. The panes are separated by spacer means secured between them located parallel to the outer perimeter edges of the panes and spaced inwardly from these edges a predetermined distance. A dead airspace between the upper and lower panes is formed inwardly of the spacer means and a flashing channel is formed around the outer perimeter between the panes outwardly of the spacer means. Flashing means is secured in the flashing channel by a resilient sealing matrix. The flashing extends outwardly from the channel a predetermined distance to form a continuous flashing border for attaching the skylight to the roof. The flashing in the channel is surrounded by the sealing matrix and is separated from the spacer a small distance to allow for thermal expansion and contraction of the skylight relative to the flashing. The skylight is preferably made of an high impact plastic. Installation can be easily accomplished by placing the edges of the skylight over an opening in a roof, nailing the flashing to the roof structure and shingling over the flashing and perimeter edges of the skylight at the top and sides thereof.

BACKGROUND OF THE INVENTION AND DESCRIPTION OF PRIOR ART 
This invention relates to a flush mounted, self-flashing skylight to be 
mounted on a roof of inclined slope. More particularly, this invention 
relates to a flush mounted, self-flashing skylight for mounting on roofs 
of inclined slope where the skylight is free floating in the flashing to 
allow for thermal expansion and contraction of the skylight relative to 
the flashing when the flashing is permanently attached to the roof 
structure. 
There have been many designs for improving conventional skylights. Many of 
the problems have been associated with providing adequate sealing of the 
skylight structure to the roof without leaking. The configuration of 
conventional skylights is generally rectangular with the skylight itself 
being flat or convexly curved. Most skylights are made of a 
light-transmissive material which may be clear or translucent. Most are 
made of a high impact, thermally expandable, plastic such as acrylics, 
polycarbonates and the like. Some are also made of glass. Most skylights 
are mounted in a framework or curb that is to be inserted through the roof 
structure. Some units have been stated to be "self-flashing" in that the 
skylight unit contains outwardly extending flanges over which is laid the 
roofing material to provide a more waterproof joint between the skylight 
and the roof. However, because most skylights are domed structures, rain 
water is often deflected around and down the skylight toward the edges 
where the joints between the skylight and the roof may permit leakage. 
This is stated to be particularly troublesome at the bottoms of skylights 
since water running over the skylight may be directed under the roofing 
material. U.S. Pat. No. 4,548,006 attempts to overcome this problem by 
providing a self-flashing structure wherein the skylight has flanged side 
edges and a raised lower end. Rain water is directed down the skylight 
between the raised flanges and "ski jumps" over the raised end. However, 
this doesn't really solve the leaking problem since water that doesn't 
"ski-jump" off the end, falls directly at the juncture of the skylight and 
the roofing shingles. Since the shingles overlap the skylight flanges, 
water can still work its way under the shingles. 
Various methods of providing sealing around skylights are taught in the 
art. Conventionally, a skylight is secured to a roof with the use of 
roofing mastic consisting of an asphaltic or resinous material. A roof 
opening is made, the roofing mastic applied on the deck around the opening 
and the flange, surrounding the curb frame to which the skylight is 
attached, is placed over the mastic and firmly pressed to create a seal. 
The flange is nailed to the roof and additional mastic is applied. 
Shingling is then completed around the skylight curb frame. 
This method is messy and not very effective unless properly done. It is 
difficult for a "do it yourself" application because the seal between the 
mastic and the curb frame must be perfect if leakage is to be avoided. 
Various means to improve upon the conventional method are disclosed in 
U.S. Pat. Nos. 3,455,073; 4,527,368 and 4,589,238. However, none of these 
relate to flush mounted skylights in that all are contained on a curb 
frame that extends above the roof surface. 
A single pane skylight is disclosed in U.S. Pat. No. 4,173,854 which 
requires the use of bow members having convex upper edges over which is 
placed flashing which must be accurately bent at various angels to 
accommodate the convex upper surface and vertical side surface of the bow 
members and also the flat rafter or sheathing surface on which the bow 
members rest. Also, the light transmitting skylight cover itself must be 
oversized relative to the roof opening and secured to the roof surface 
with screws or other fastening means. Unless very accurately installed, 
the attachments of the skylight cover and flashing present numerous 
leakage problems. For example, the thermal expansion and contraction of 
the plastic skylight cover can cause the screws, with which it is secured 
to the roof, to work loose and cause leakage. 
Provisions for thermal expansion or contraction are not generally made in 
prior art devices. A rolling seal arrangement to provide for thermal 
expansion in skylights mounted in a curb frame is described in U.S. Pat. 
No. 3,455,073. 
Although there is considerable art in skylight technology, there has not 
heretofore been available a simple, inexpensive, self-flashing, 
water-tight, flush mountable dual pane skylight. 
OBJECTS AND BRIEF SUMMARY OF THE INVENTION 
It is therefore an object of the present invention to provide for a 
water-tight, self-flashing dual pane skylight which can be mounted flush 
with an inclined roof surface without requiring a curb frame. 
It is also an object of this invention to provide for a water-tight, 
self-flashing skylight wherein the skylight is free floating in the 
flashing to allow for thermal expansion or contraction of the light 
transmitting skylight material. 
Another object of this invention is to provide a self-flashing, dual pane 
skylight wherein the skylight is flush mounted in the roof in such a 
manner that the flashing is utilized as an extension of the shingles to 
allow for a water resistant installation. 
These and other objects may be realized by means of a dual pane structure 
generally consisting of upper and lower panes of light transmitting 
material having the same outside perimeter dimensions, (preferably 
rectangular) wherein the panes are separated by means of spacers 
sandwiched between the panes in generally parallel position relative to 
the outside edges of the panes but being located inwardly therefrom a 
predetermined distance. With the spacers being so located, they form a 
continuous seal between the two panes inwardly from their perimeters, 
thereby creating a dead air space between the panes inwardly of the 
spacers and a flashing channel outwardly thereof. 
The flashing channel is sufficiently deep that flat strips of flashing can 
be imbedded in the channel in a resilient sealing matrix and extend 
outwardly of the channel to form a flat flange surface which is attachable 
to the roof structure. The flashing extends into the channel almost to the 
spacers and is surrounded by the resilient sealing matrix which allows the 
flashing and skylight panes to float relative to each other within the 
channel as the panes thermally expand or contract. This allows the 
flashing to be permanently attached to the roofing and be covered at the 
top and sides of the skylight structure by shingles with the flashing 
serving as an extension of the shingles. The lower portion of the flashing 
also serves as an extension of the shingles and does not require that the 
lower flashing be covered by a row of shingles. Rather, the lower flashing 
overlaps the next lower shingle row. Thus, the skylight structure is flush 
mounted to the roof and water running down the skylight and around the 
sides is not backed up by the skylight structure nor is there any 
significant leakage. Of course, it may still be desirable to place a 
sealing material about, i.e. under, over or both, the flashing as an added 
precaution against leakage. 
The upper skylight pane will preferably be convex and various domed shapes 
will be presented in the detailed description that will hasten water flow 
off the skylight.

DETAILED DESCRIPTION OF THE INVENTION 
There is shown in FIGS. 1-4 one complete and preferred embodiment of the 
invention. FIGS. 1-3 show a skylight 10 consisting of upper pane 11 and a 
lower pane 12 separated by a continuous spacer 13. Panes 11 and 12 are 
generally rectangular in shape having opposing side edges and a top and 
bottom edge. Upper pane 11 contains a dome 14. The preferred dome shape, 
as shown in FIG. 1, generally has five sides 15a-e connected by rounded 
corners 16a-e. The dome 14 is formed by the central portion of pane 11 
depending upwardly and inwardly from the walls and corners. As shown in 
FIG. 1, a generally rounded forward corner 16a has sides 15a and 15b 
angling outwardly and backwardly therefrom toward the sides of the pane 
terminating at rounded corners 16b and 16c. From rounded corners 16b and 
16c, sides 15c and 15d depend backwardly and parallel to the side edges of 
upper pane 11 to corners 16d and 16e which, in turn are interconnected by 
backside 15e which is parallel to the lower edge of pane 11. Other dome 
shapes may be utilized. However, the shape just described is deemed to be 
the most functional as will be described below. 
The spacer 13 is located inwardly from the outside perimeters of panes 11 
and 12 a predetermined distance but must be located outwardly from dome 
14. Spacer 13 is located parallel to the side and end edges of the panes 
and forms a continuous barrier. Inside of the barrier between the upper 
and lower panes is a dead air space 17 and outside the barrier between the 
panes is a flashing channel 18. Spacer 13 may be made in the form of 
strips or may be one piece. It is sandwiched between the panes and fixed 
in place by adhesives or other suitable means to create a water tight 
seal. 
The distance spacer 13 is located inwardly from the outside edges of panes 
11 and 12 will be determined by the depth desired for flashing channel 18. 
Panes 11 and 12 and spacer 13 may be made of any suitable light 
transmitting material, and may be transparent or translucent. Preferably a 
high impact acrylic or polycarbonate type of translucent plastic will be 
used such as marketed under such tradenames as Lexan and Plexiglas. It is 
also preferable that both panes and the spacer be made from the same 
plastic material so they will have the same coefficient of thermal 
expansion. 
Flashing channel 18 runs around the entire outer perimeter of skylight 10 
defined by spacer 13 and the portions of panes 11 and 12 extending 
outwardly therefrom. Into this channel is inserted flat strips of flashing 
material 19 which may be made of any suitable material such as aluminum, 
steel, galvanized tin, plastic and the like. The flashing 19 is held in 
channel 18 by means of a resilient sealing matrix 20. This may be any 
suitable caulking or mastic type of substance made of plastic or asphaltic 
compositions. Flashing 19 is preferably not inserted into channel 18 at a 
depth to be in contact with spacer 13. Rather, a small space is left 
between the flashing 19 and spacer 13 and filled with the matrix to allow 
for thermal expansion and contraction of panes 11 and 12. 
FIG. 4 is more explicit in showing how flashing 19 is held in channel 18 
surrounded by matrix 20. 
Flashing 19 is preferably made of strips 19a-d as best shown in FIG. 5. 
Upper strip 19a overlaps side strips 19b and 19c which, in turn, overlap 
bottom strips 19d much in the same manner as roof shingles overlap each 
other on a downward slope. This prevents water running over the flashing 
from seeping under the various flashing strips on a downward course. 
However, in the alternative, flashing 19 could be made of a single 
continuous strip. In that case, to install the flashing, spacer 13 would 
have to be sealed to one pane, the flashing would then be inserted about 
the spacer and the second pane would then be sealed to the spacer. The 
matrix would be appropriately applied into the flashing channel at any 
suitable point of the joining operation. 
Flashing strips 19 extend outwardly from channel 18 a predetermined 
distance to provide for installation of the skylight 10 and the sealing of 
the same against leakage. 
FIGS. 1-3 also show the manner in which the skylight may be installed. 
Assuming one is starting with an existing roof, an appropriate sized 
opening is created by cutting through the shingles and sheathing. 
Preferably the skylight will be of a width that it will fit between 
adjacent rafters 21 and 22 as shown in FIG. 3 with the outer edges, from 
about the spacer 13 and out, resting on the sheathing 23 over the rafters. 
If desired, as shown in FIG. 2, an appropriate top header 24 and bottom 
header 25 may be secured between the rafters below the sheathing 23 for 
framing purposes. With the opening framed as described, the skylight shaft 
may be completed by the placement of drywall 26. 
Although not absolutely necessary, it is preferable to surround the opening 
with a metal frame before installing the skylight 10. An appropriately 
angled frame 27 is placed over the sheathing 23 and down the sides of the 
drywall 26. As shown in FIG. 3, the frame sides 27b and 27c are at a 
90.degree. or right angle. As shown in FIG. 2, the top frame end 27a is at 
an obtuse angle and the bottom frame end 27d is an acute angle. The angles 
will, of course, depend upon the pitch or slope of the roof. The frame may 
be made in strips or of a single piece and is appropriately secured around 
the opening by nails, adhesives and the like. 
Before placing the skylight 10 over the opening, a continuous bead of 
silicone or other appropriate sealant 29 is placed on the upper surface of 
frame 27. The outer edges of lower pane 12, from about spacer 13 and out, 
are then positioned over the silicone bead and the outer edges of the 
skylight are pressed to create a seal between the frame 27 and the lower 
pane 12. Some sealant 29 may extend out past the edge of the pane to 
underlie outwardly extending flashing 19. If desired, additional sealant 
29, or mastic, may be placed on the sheathing outside of frame 27 to 
provide a sealant under the flashing. The flashing 19, extending outwardly 
over the sheathing 23 is then secured to the roof by nails 28. Preferably 
the flashing 19 will be positioned over the rafters 21 and 22 and headers 
24 and 25 so that the nails 28 will be secured through the sheathing and 
into the framing. When secured in this position, the flashing will not 
move relative to the roof. However, the skylight is permitted to thermally 
expand and contract relative to the flashing 19 in the flashing channel 18 
as best shown in FIG. 4. The silicone seal 29 does not inhibit the small 
amount of thermal expansion or contraction which will take place. However, 
no leakage occurs between the flashing and skylight due to the sealing 
matrix 20 holding the flashing 19 in channel 18. 
When the flashing has been nailed to the roof, the installation can be 
completed by proper placement of shingles 30 around the skylight in the 
manner shown in FIGS. 1-3. Assuming, for purposes of illustration, the 
placement is of 12" shingles having a 7" overlap and 5" exposure. 
Preferably, the bottom edge of lower flashing 19d will be in alignment 
with the lower edge of a row of shingles as shown in FIG. 1. Each 
ascending row of shingles will extend over side flashing strips 19b and 
19c at the sides of the skylight nd also extend over the upper side 
perimeter surface of pane 11 in the manner shown in FIGS. 1 and 3. If 
desired, a mastic or other sealant can be placed over the flashing before 
shingling to create a tighter seal. 
As will be noted from FIGS. 1 and 2, the lower flashing 19d serves as part 
of the shingle structure in that it overlaps the lower row of shingles 
involved in the placement of the skylight and covers the nails used in 
securing that row of shingles. Hence, there is no need to cover the lower 
flashing 19d with shingles. 
As shown in FIGS. 1 and 2, when the upper involved row of shingles is 
reached, the lower edge of the shingles in that row will overlap the upper 
flashing 19a and also the upper perimeter edge of pane 11. Thus, when 
completely installed, the self-flashing skylight 10 will be flush mounted 
in the roof and water coursing down the roof will not meet any abutment, 
other than the skylight dome, to cause any water backup or seepage under 
any shingle or portion of the skylight. The shape of the dome shown in 
FIGS. 1-3 minimizes any impediment in water flow. Water will be diverted 
away from the dome at rounded front corner 16a, flow at an angle down 
sides 15a and 15b to corners 16b and 16c and off onto the roof. Water not 
flowing to the roof at the sides of the skylight will then flow down past 
sides 15c and 15d and off the lower portions of side flashing 19b and 19c 
and bottom flashing 19d onto the roof. 
Rain falling directly on doom 14 will drain by gravity and fall from the 
edges and bottom in the manner just described. 
Other dome shapes may also be utilized. FIG. 5 shows a skylight 10 having a 
dome 14 symmetrically shaped. Other shapes are shown in FIGS. 6a-c. 
FIG. 6a shows skylight 10 having a spherical dome 14. FIG. 6b illustrates a 
skylight 10 having downwardly sloping parallel prism shaped domes 14a and 
14b wherein the domes are formed from upwardly and inwardly sloping sides 
15f and 15g meeting at an apex and sloping ends 15h and 15j which are 
sealed to the sides to complete the dome. FIG. 6c shows a skylight 10 
having a cylindrical dome 14 with a pointed slanted front end 15k and an 
arcuate sloped back end 15m. 
Obviously other modifications may be made without departing from the scope 
of the invention. The bottom pane does not necessarily have to be flat and 
can parallel the shape of the dome in the upper pane. Also, while 
preferable to have a dome, the upper pane could be flat. Multiple 
skylights can be placed side by side with reinforcement between the 
skylights. These modifications and other functional equivalents are deemed 
to be part of the invention which is to be limited only in scope by the 
appended claims.