TUB BOX FOR PLUMBING INSTALLATION

BOITE A TUYAUX POUR INSTALLATION DE PLOMBERIE

English Abstract

A tub box (20) for use in enclosing an end of a drain pipe (46) in a concrete slab floor of the type having a concrete slab (42) and a vapor barrier film (56), and permitting a plumbing connection to the drain pipe. The tub box comprises a container having side walls (22), a closed bottom (24) and a top edge (28) defining an open top (26), the top being adapted to receive a lid (32); and a radially outwardly-protruding flange (40) on the side walls, axially spaced below the top edge by a distance (D) approximately equal to the thickness of the concrete slab, for sealing attachment to the vapor barrier film. The tub box (20) is used by placing it in the ground (48) on which the concrete slab is to be poured, with the flange at the surface of the ground and the drain pipe extending into the container interior through the opening (44) in the side wall. The vapor barrier film (56) is laid on the ground surface and is sealed to the flange (40). The concrete slab is poured on the ground over the vapor barrier film to a thickness approximately equal to the axial distance between the flange and the top edge of the container.

French Abstract

Une boîte à tuyaux (20) est destinée à enfermer une extrémité dun tuyau de drain (46) dans un plancher à dalle de béton du type comportant une dalle de béton (42) et un pare-vapeur (56), et permettant un raccord de plomberie au tuyau de drain. La boîte à tuyaux comprend un contenant ayant des parois latérales (22), un fond fermé (24) et un bord supérieur (28) définissant un dessus ouvert (26), le dessus étant adapté pour recevoir un couvercle (32); et une bride en saillie se déployant radialement vers lextérieur (40) sur les parois latérales, espacée axialement sous le bord supérieur par une distance (D) approximativement égale à lépaisseur de la dalle de béton, pour étanchéiser laccessoire au pare-vapeur. La boîte à tuyaux (20) est utilisée en la plaçant dans le sol (48) sur lequel la dalle de béton doit être versée, la bride étant à la surface du sol et le tuyau de drain se prolongeant dans le contenant intérieur par louverture (44) dans la paroi latérale. Le pare-vapeur (56) est posé sur la surface du sol et scellé à la bride (40). La dalle de béton est versée sur le sol au-dessus du pare-vapeur à une épaisseur approximativement égale à la distance axiale entre la bride et le bord supérieur du contenant.

Claims

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Claims


1. A tub box for use in enclosing an end of a drain pipe in a concrete slab
floor of the type having a concrete slab and a vapor barrier film, and
permitting a plumbing connection to the drain pipe, comprising:

(a) a container having side walls, a closed bottom and a top edge
defining an open top, the top being adapted to receive a lid;

(b) a radially outwardly protruding flange on the side walls, axially
spaced below the top edge for sealing attachment to the vapor
barrier film.

2. A tub box according to claim 1, wherein the flange is axially spaced
below the top edge by a distance approximately equal to the thickness of
the concrete slab.

3. A tub box according to claim 1, wherein the container has an opening
therein to receive the drain pipe.

4. A tub box according to claim 3, wherein the opening is in the side wall,
axially spaced below the flange.

5. A tub box according to claim 1, further comprising a radially outwardly
extending ledge in the sidewalls at the top edge of the container adapted
to receive the lid.

6. A tub box according to claim 1, further comprising the lid.

7. An enclosed drain pipe structure in a concrete slab floor, comprising:
a concrete slab on a ground surface, with a vapor barrier film
between the concrete slab and the ground surface;



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a container having side walls, a closed bottom, a top edge defining
an open top, a removable lid covering the open top, and a radially
outwardly protruding flange on the side walls, axially spaced
below the lid;

the container being positioned with the container bottom in the
ground, an end of the drain pipe extending into the container
through an opening in the side wall, the vapor barrier film sealed to
the flange, and the lid adjacent to the upper surface of the concrete
slab.

8. A method of enclosing an end of a drain pipe in a concrete slab floor of
the type having a concrete slab and a vapor barrier film, and permitting a
plumbing connection to the drain pipe, comprising the steps of:

(a) providing a container having side walls, a closed bottom, a top
edge defining an open top, the top being adapted to receive a lid, an
opening in the container side wall or bottom to receive an end of
the drain pipe, and a radially outwardly protruding flange on the
side walls, axially spaced a distance below the top edge;

(b) placing the container in the ground on which the concrete slab is to
be poured, with the flange at the surface of the ground and the
drain pipe extending into the container interior through the
opening;

(c) laying the vapor barrier film on the ground surface;
(d) sealing the vapor barrier film to the flange;



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(e) pouring the concrete slab on the ground over the vapor barrier film

to a thickness approximately equal to the axial distance between
the flange and the top edge of the container; and

(f) placing a removable lid on the container.

Description

CA 02752360 2011-09-15
1
Tub Box for Plumbing Installation
Field of the Invention
The invention pertains to devices for use in plumbing installations.
.. Background of the Invention
In the residential construction industry, it is common practice to
rough in the drainage in the basement floor for use in the event that the
homeowner later wishes to install a plumbing fixture in the basement. This
roughing-in involves laying a drainpipe in the dirt floor connected to the
drainage system and affixing a vertically-extending pipe at its end before
pouring the concrete slab. In modern basement floor construction, a vapor
barrier film may be provided under the concrete slab to seal the floor and in
particular to prevent radon gas in the ground from entering the basement.
The vapor barrier film is laid on the dirt, is sealed to the vertically-
extending
.. pipe, and the concrete slab is poured on top of the film. The vertical pipe
protrudes above the concrete slab and shows the location of the drain pipe
when it is later needed. Although this marking of the location of the drain is

of assistance, in order to use the drain the plumber has to break up the
concrete slab around the vertical pipe, dig around the drain pipe and install
a
trap on the drain pipe before attaching a bathtub or other plumbing fixture to
the drain. This operation requires substantial labor and punctures the vapor
barrier film. It is difficult to re-seal the film, with the result that the
vapor
barrier seal may be broken and gases in the ground may leak into the
basement.
It is known in the construction industry that a tub box can be used to
enclose a drain trap in a concrete slab floor, in order to facilitate
connection

CA 02752360 2011-09-15
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of the plumbing fixture to a drainage line. Examples in the patent literature
are Logsdon, US 3,593,344, and King, US 6,264,056.
Summary of the Invention
The invention provides a tub box for use in enclosing an end of a
drain pipe in a concrete slab floor of the type having a concrete slab and a
vapor barrier film, and permitting a plumbing connection to the drain pipe
while maintaining a secure seal to the vapor barrier film. The tub box
comprises a container having side walls, a closed bottom and a top edge
defining an open top, the top being adapted to receive a removable lid, and a
radially outwardly-protruding flange on the side walls, axially spaced below
the top edge by a distance approximately equal to the thickness of the
concrete slab, for sealing attachment to the vapor barrier film.
The invention further provides a method of enclosing an end of a
drain pipe in a concrete slab floor of the type having a concrete slab and a
vapor barrier film, and permitting a plumbing connection to the drain pipe.
A container is provided having side walls, a closed bottom, a top edge
defining an open top, the top being adapted to receive a lid, an opening in
the container to receive an end of the drain pipe, and a radially outwardly-
protruding flange on the side walls, axially spaced a distance below the top
edge. The container is placed in the ground on which the concrete slab is to
be poured, with the flange at the surface of the ground and the drain pipe
extending into the container interior through the opening. The vapor barrier
film is laid on the ground surface and is sealed to the flange. The concrete
slab is poured on the ground over the vapor barrier film to a thickness
approximately equal to the axial distance between the flange and the top
edge of the container. A removable lid is placed on the container.

CA 02752360 2011-09-15
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Further aspects of the invention and features of specific embodiments
of the invention are described below.
Brief Description of the Drawings
Figure 1 is a vertical cross-sectional view through an embodiment of
the tub box as installed in a concrete slab floor.
Figure 2 is an isometric view of the tub box of Figure 1.
Detailed Description of the Preferred Embodiments
The tub box 20 is made for use with a concrete slab floor in which,
during building construction, a concrete slab is laid on the ground of the
basement, with a drain pipe buried in the ground under the slab and
connected to the drainage system, and a vapor barrier film is employed.
The tub box 20 comprises a container made of impermeable, high-
impact plastic, for example ABS, by injection or blow molding. It has four
side walls 22 and a bottom wall 24, and is open at the top 26. At the top
edge 28, a radially-outwardly extending ledge 30 is provided, to receive a
lid 32. The ledge has a horizontal section 34 to support the lid, and a
vertical section 36 which forms a perimeter within which the lid fits.
A flange 40 protrudes radially outwardly from the sidewalls. The
flange is spaced between the top edge and the bottom of the container, and
more specifically is positioned axially downward from the top edge by a
distance D which is approximately equal to the thickness of the concrete
slab 42 in which the container is to be embedded, as explained below.

CA 02752360 2011-09-15
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The container has an opening 44 in one side wall 22 below the level
of the flange 40, sized to receive the end of the drain pipe 46. The opening
44 may be made at the time of manufacture of the container or be drilled in
the side wall at the time of installation, for convenient alignment with the
drain pipe. Alternatively, the opening 44 may be in, or be made in, the
bottom of the container rather than the side wall, depending upon the
requirements and preferences for the installation.
The container may be of any size that is suitable for a particular
installation. An exemplary size is 16 inches (40.6 cm) high, 14 inches (35.6
cm) long and 12 inches (30.5 cm) wide, the length and width being
measured at the top of the side walls, tapering to 13 inches (33 cm) long and
11 inches (28 cm) at the bottom. The ledge may have a width of 5/8 inches
(1.6 cm) and a height of 5/8 inches (1.6 cm). The distance D may be about
4 inches (10 cm).
The container 20 is installed in the basement floor during building
construction in the following manner. The container is placed in a dug-out
hole in the dirt 48, with the end 50 of the drain pipe 46 extending through
the opening into the interior of the container. Dirt is filled in around the
container, to about the level of the flange. A rubber sealing boot 52 is put
over the pipe end 50, to form an impermeable seal between the side wall 22
of the box and the pipe 46. An end cap 54 is put on the end of the pipe. A
vapor barrier film 56 is laid on the dirt floor and is sealed to the box by
applying a bead of adhesive 58 to the upper surface 60 of the flange and
pressing the film against it. The lid 32 is put on the container and the
.. concrete slab 42 is then poured on top of the film to a thickness about
equal
to the distance D from the flange to the top edge of the container. The
installation thus provides a visual indication on the concrete slab floor,
namely the lid of the box, as to the location of the drain pipe, and provides
a

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complete seal with the film, i.e. by virtue of the seal to the flange and the
seal around the side wall opening. The seals are not broken when a
plumbing fixture is subsequently connected to the drain pipe.
To use the installation, the lid is lifted off, the end cap is removed,
and a conventional drain trap is attached to the open end of the drain pipe,
within the tub box 20. A plumbing fixture, such as a bathtub, is then
connected to the trap.
As will be apparent to those skilled in the art in the light of the
foregoing disclosure, many alterations and modifications are possible in the
practice of this invention without departing from the scope thereof. As one
example, the flange can be any shape which permits sealing attachment of
the vapor barrier film to the container. As another example, the top edge of
the container can be plain with no ledge, and the lid can be placed on top of
and overhanging the top edge. As a further example, the tub box may be
round in horizontal cross-section, rather than rectangular as illustrated.
CA 2752360 2018-02-21

Representative Drawing