[0001] This invention relates to an elongate air sealing member made from a flexible, compressible,
water repellant material having,
inter alia, thermal insulating properties. More particularly, this invention relates to an auxiliary
insulating profile for installation in a cavity wall.
[0002] In certain types of building construction, known as insulated, cavity wall construction,
it is customary to have a construction comprising an outer wall, an air gap or cavity
that is eventually vented, and an inner wall. Such a construction usually includes
insulation boards or insulation materials applied to the inside cavity wall in such
a manner that a venting space remains between the insulating boards and the outer
wall. It has been shown that natural convection, meaning thermal air circulation,
causes substantial heat losses around insulation layers and/or insulation boards,
as compared to calculated theoretical values.
[0003] Thus, in order to obtain a proper thermal insulated cavity wall, adequate steps must
be taken to prevent natural convection from occurring. This requires that the insulation
boards fit tightly together so as to form an airtight shield. Openings of only a few
millimeters in width can create natural convection currents with corresponding substantial
heat losses.
[0004] Even more important, however, is to be able to seal all openings around the top and
bottom edges of insulation layers, around wall openings and vertical corner connections
of cavity walls, so as to prevent normal air infiltration and thermal convection from
occurring.
[0005] In practice, the inner wall is normally not smooth at its cavity side, i.e. there
are projecting cement residues and brick dimensional tolerances which prevent insulating
boards from coming to rest perfectly against the inner-wall. Furthermore, the top
and bottom edges of insulation layers are normally not sealed in an airtight manner
with other building parts. Therefore, it is clear that in order to obtain proper thermal
insulation, it is necessary to take extra precautions and work very accurately, which
is time-consuming and hence an expensive way of building an insulated, cavity wall
construction.
[0006] It is an object of this invention to provide an auxiliary member or cavity sealing
profile for use in insulated cavity wall construction that is simple to use, and that
prevents the circulation of air via natural convection around the insulating layer.
It is a further object of this invention to provide a method of insulating cavity
walls, which utilizes the cavity sealing profile of this invention.
[0007] The auxiliary member comprises essentially an L-shaped cross section of a flexible,
compressible, water repellant material having thermal insulation properties. Such
a profile is adapted to fit against the butt edge of an insulating board. Other types
of L-shaped profiles can be employed to accommodate insulating boards having tongue-and-groove
edges, or ship-lapped edges. L-shaped profiles containing various other minor modifications
can also be employed to accommodate the edges of specially formed insulating boards,
and these are contemplated as falling within the scope of the present invention.
[0008] It is clear that any flexible, compressible, water repellant material having thermal
insulating properties can be employed in the practice of this invention. Such materials
include, for example, synthetic foams made from polyethylene, polypropylene, polyurethane,
ethylene vinyl acetate, polyvinyl chloride, polystyrene and the like, both extruded
and expanded. Preferably, elastic, closed-cell, crosslinked and non-crosslinked polyolefin
foams are employed.
[0009] Still more particularly, cavity sealing profiles comprising closed-cell, non-crosslinked
polyethylene foam or mixtures containing such foams are utilized in the present invention.
These materials have very good thermal insulating properties, are not susceptible
to hydrolysis and absorb practically no water. Moreover, such polyethylene foam materials
are resilient and can absorb the tensile and compressive stresses arising from temperature
fluctuations or load pressures. Due to their resilience they are able to deform under
stress and pressure and thereby fit tightly into a cavity wall without cracking. Thus,
cavity sealing profiles made from such materials form a tight compression fit within
the cavity that effectively prevents any heat losses from occurring via thermal convection.
[0010] The desired profiles can be milled to shape from block foam, molded to shape, or
extruded to shape through special dies. However prepared, the cavity sealing profile
is adapted to be placed in the cavity of the wall in such a manner that the outer
longitudinal face of the vertical member of the L-shaped profile is adjacent to the
inner surface of the exterior wall, while the longitudinal edge of the horizontal
limb of the L-shaped cavity sealing profile is adjacent to the inner cavity surface
of the interior wall.
[0011] One advantage of the cavity sealing profile or auxiliary profile described herein
is in the construction of the cavity wall itself. In some countries, both inner and
outer cavity walls are progressively constructed at the same time. By seating the
auxiliary profile at the base of the cavity of the cavity wall, it forms a spacer
between the inner and outer walls, thereby providing and maintaining a proper cavity
width. At the same time, the auxiliary profile helps to prevent cold bridges from
occurring at connections between insulation surfaces and other construction parts.
Furthermore, as a construction aid, once the longitudinal surface of the horizontal
limb of the cavity sealing profile is plumb and level, insulation boards subsequently
added thereto will also automatically be level. Once the top of the cavity wall is
reached, a second cavity sealing profile is attached which is in opposition to the
base cavity sealing profile, thereby effectively sealing all air leaks both at the
bottom and at the top of the cavity. Obviously, additional cavity sealing profiles
can be installed at vertical corners and around wall openings, such as doors and windows.
[0012] In addition to the other functions previously mentioned, the cavity sealing profiles
of the present invention can serve to discharge any condensate or rain water that
may occur in the cavity between the insulating layer and the inner surface of the
exterior wall. In a preferred embodiment of the present invention, the top surface
of the cavity sealing profile, is sloped downwardly to the exterior wall. Thus, the
inclined top surface conducts any water or condensate towards the direction of the
external wall. The water and condensate can be easily discharged via openings provided
near the lowest point of the inclined top surface leading to the exterior of the outer
wall.
[0013] For an even more effective discharge of cavity wall condensate or rain water that
might collect within the cavity, a moisture-proof, tear resistant, flexible film can
be employed which serves as a condensate or water barrier. As a preferred embodiment
such a film is made to adhere to the sloping surface of the cavity sealing profile.
The top edge of this film is secured to the exterior surface of the insulation board,
whereas the bottom edge of this film leads to the outside of the exterior wall via
a horizontal joint in the outer wall. Such a film effectively serves as a water impermeable
barrier and conduit to the exterior surface of the outer wall for any rainwater or
condensate that finds its way inside the cavity wall. The top of this film can be
conveniently secured to the exterior surface of the insulation boards by passing the
film through a horizontal joint of the insulation layer in such a manner as not to
disturb the air tightness of the joint.
[0014] Any type of moisture proof film can be utilized in connection with this invention.
Due to the hard usage to which such a film is subjected during construction, it is
desirable to employ a film of sufficient thickness so as to be tear and puncture resistant,
but which still retains its flexibility. Cast or blown films made from linear low
density polyethylene resins are particularly useful in the practice of this invention.
They exhibit exceptional tear, toughness and puncture resistant properties and are
completely water resistant. The film can be so attached to the auxiliary profile that
it allows a horizontal overlap which can be either a loose-laid overlap or which can
be sealed together at the job site.
[0015] Some embodiments of the present invention will now be described, by way of example,
with reference to the accompanying drawings, in which:
Figure 1 is a perspective view of an elongate cavity sealing profile in combination
with a moisture-resistant sheet material;
Figure 2 is a cross-sectional view of a cavity wall construction, showing the placement
of an insulation member between two cavity sealing profiles of Figure 1;
Figures 3 and 4 represent vertical and horizontal cross-sections, respectively, of
a cavity wall located around a window or door, provided with an insulating member
contained by a cavity sealing profile of Figure 1;
Figure 5 is a horizontal cross-sectional view of a corner of a cavity wall, provided
with insulating members that are contained by a cavity sealing profile; and
Figures 6 and 7 show vertical cross-sections of two variations of the cavity sealing
profile of Figure 1.
[0016] One embodiment of an elongate cavity sealing profile (1) is shown in Figure 1, which
has a substantially L-shaped cross section, and which is made from a flexible, compressible
material having thermal insulating properties. The free end of the vertical limb (2)
of the L-shaped cavity sealing profile (1) has a top surface (3) extending obliquely
downwards from its inner longitudinal face (4) to the direction of its outer longitudinal
face (5). A moisture-resistant, film material (6) may be fixed to the top sloping
surface (3), said film being of sufficient length so as to substantially extend beyond
the top and bottom edges of the sloping surface (3).
[0017] As shown in Figure 2, the cavity sealing profile (1) is adapted to be a compression
fit in the base of the cavity (7) of a cavity wall (9,10). The bottom longitudinal
face (11) of said profile rests on the foundation (8) or the base of the cavity (7),
while the outer longitudinal face (5) is adjacent to the inner surface of the exterior
wall (10). The longitudinal edge (13) of the horizontal limb (12) rests adjacent to
the inner surface of the interior wall (9). Between the inner longitudinal face (4)
of the sealing profile (1) and the cavity side of the inner wall (9), a part of an
insulating board (14) is adapted to be confined therein. It is clear that the sealing
member (1) should be of such a length as to seal the entire length of the cavity wall.
[0018] The inclined top surface (3) of the cavity sealing profile (1) is designed so as
to collect any rain water or moisture condensate present in the cavity (7), and discharge
it to the outside of the exterior wall (10). Preferably, the sealing profile (1) is
positioned in such a manner that the lowest point of the top surface (3) is flush
with a horizontal joint (15) formed by two rows of bricks in the exterior wall (10).
[0019] For the effective discharge of water, the moisture-proof, tear resistant, flexible
film (6) is affixed to the top surface (3) of the cavity sealing profile (1). The
top edge of this film can be readily held in place by passing it through a joint (20)
formed between two insulation boards (14), care being taken not to disturb the air
tightness of the joint. The lower edge of the film can be sloped downward and led
to the exterior via the horizontal joint (15). The top of the cavity wall can be enclosed
by reversing the cavity sealing profile so that the longitudinal face (11) of said
profile (1) is adjacent to the ceiling (16).
[0020] Figures 3 and 4 show a vertical and horizontal cross-section of a cavity wall adjacent
to a window or door opening, and shows how the cavity sealing profile (1) can be mounted
in such a case. Figure 3 shows the use of a course of brick or stone laid on edge
(17), and the placement of the sealing profile (1) at the appropriate height against
the inner face of said course of brick or stone. Such techniques, can be utilized,
for example, when said edge (17) is a lintel or ornamental supporting structure of
natural stone, having a larger vertical dimension than the outer longitudinal face
(5) of the cavity sealing profile. Again the joints (15) between the lintel and superposed
brick function as an outlet channel for any moisture or water the cavity may receive.
The cavity formed between the frame (18) and the bottom longitudinal face (11) of
the sealing member (1) can be filled with an insulation member (14) and then with
an expandable foam or soft insulation material (19). In the vertical portion of the
wall (see Fig 4), the cavity sealing profile can be placed against the frame (18)
without objection, since its positioning near a joint is not necessary in the vertical
plane.
[0021] Figure 5 shows an embodiment of how a cavity sealing profile (1) can function as
a cavity sealer in the situation where the external walls are set at right angles
to each other. Such a positioning of the sealing profile results in effectively sealing
any gaps created by improperly fitting insulating boards. Since even small gaps of
one or two millimeters can create thermal convection with resulting heat loss, the
use of a cavity sealing profile to seal a corner joint is a further advantage of the
present invention.
[0022] Figures 6 and 7 show two cross sectional variations of the sealing profile (1). The
ridged horizontal limb ensures that the edges of the insulation board (14) having
a complementary profile, fit snugly and remain air tight. The fact that the cavity
sealing profile can be slightly deformed when the edge of the insulation board is
pressed against the L-shaped surface of the cavity sealing profile ensures a tight
fit. The result is that excellent sealing is obtained and no undesirable air circulation
or thermal convection occurs between the inner surface of the interior wall and the
insulation boards.
[0023] It is clear that, without departing from the scope of the present invention, modifications
can be made for instance as regards the profile of the sealing member. Likewise, the
sealing member can be used between any two spaced-apart walls to prevent undesirable
air circulation or convection from occurring.
1. An elongate cavity sealing profile made of flexible, thermally insulating, compressible
material, wherein said sealing profile (1) has a substantially L-shaped cross-section
and is adapted to be a compression fit in a cavity space (7), formed by opposing interior
and exterior walls (9,10), with said profile located in such a manner that the outer
longitudinal face (5) of its vertical limb (2) is adjacent to the inner surface of
the exterior wall (10), and the longitudinal edge (13) of its horizontal limb (12)
is adjacent to the cavity surface of the interior wall (9), said profile being of
such a configuration as to accommodate the edge of an insulating board (14).
2. A profile as claimed in Claim 1, wherein the top face (3) of said profile extends
obliquely downwards from its inner longitudinal face (4) to its outer longitudinal
face (5).
3. A profile as claimed in Claim 1 or Claim 2, wherein said profile (1) is provided
with a moisture-proof, tear resistant, flexible film (6), which is fastened to the
top face (3) of the vertical limb (2) of said profile, said film extending in both
directions beyond the top face (3) of said profile.
4. A profile as claimed in any one of Claims 1, 2 and 3, wherein the top surface of
the horizontal limb (12) of said profile is in the form of a tongue-and-groove joint.
5. A profile as claimed in any one of Claims 1, 2 and 3, wherein the top surface of
the horizontal limb (12) of said profile is in the form of a ship-lap joint.
6. A profile as claimed in any one of the preceding claims wherein the compressible
material is a closed-cell, non-cross-linked polyethylene foam.
7. A profile as claimed in any one of the preceding claims, wherein the profile is
as defined in Claim 3, characterized in that the said film is a linear low density
polyethylene resin film.
8. A method of constructing thermally insulated cavity walls characterized by inserting
at the base of the cavity (7) formed by said cavity walls (9, 10) an elongate cavity
sealing profile (1) made of a flexible, thermally insulating, compressible material
and having a substantially L-shaped cross-section, the profile being located with
the outer longitudinal face of its vertical limb adjacent to the inner surface of
the exterior wall and the longitudinal edge of its horizontal limb adjacent to the
cavity surface of the interior wall; inserting an edge of a thermal insulating board
(14) in the L-shaped portion of said profile (1); progressively constructing the inner
and outer cavity walls (9, 10) while adding additional insulating boards (14) until
the desired height is obtained; and capping the upper edge of the uppermost insulating
board (14) with a second said elongate sealing profile (1) which is placed in opposition
to the base profile (1).
9. A method as claimed in Claim 8, wherein said elongate sealing profile is a profile
as defined in any one of Claims 2 to 7.
10. A method as claimed in Claim 9, wherein a moisture-proof, tear resistant flexible
film (6) extends from the lowermost insulating board over the top surface (3) of the
profile (1) to a joint (15) in the exterior wall (10) to direct condensation or water
from the cavity (7).
11. A cavity wall comprising opposed interior and exterior walls and an insulating
board adjacent the cavity surface of the interior wall, characterized in that an elongate
cavity sealing profile (1) made of flexible, thermally insulating, compressible material
and having a substantially L-shaped cross-section extends across the cavity (7) with
the outer longitudinal face (5) of one limb (2) adjacent to the inner surface of the
exterior wall (10) and the longitudinal edge (13) of the other limb (12) adjacent
to the cavity surface of the interior wall (9) and an edge of the insulating board
(14) is located in the space defined between the profile (1) and the interior wall
(9).
12. A cavity wall as claimed in Claim 11, wherein the profile (1) is located at the
base of the cavity (7).
13. A cavity wall as claimed in Claim 12 wherein a second said profile (1) is similarly
located at the top of the cavity.
14. A cavity wall as claimed in any one of Claims 11 to 13, wherein the profile (1)
is as defined in any one of Claims 2 to 7.
15. A cavity wall as claimed in any one of Claims 11 to 14 wherein a moisture-proof,
tear resistant, flexible film (6) extends from the insulating board (14) over the
top surface (3) of the profile (1) to a joint (15) in the exterior wall (10) to direct
condensation or water from the cavity (7).