Background of Invention

The invention is directed to renovating wet rooms in buildings and especially to renovating bathrooms of apartment buildings. Presently two methods are commonly used when renovating the sewerage in old houses, such as in apartment buildings. A faster and cleaner method is lining the inner surface of the existing sewerage pipes; then the piping and the structures do not need to be dismantled at all or only to a small extent. The drawback in this method is that some of the pipes may have a small diameter and lining reduces the internal diameter further.

A slower method, which also causes more disturbance to residents during the renovation, is to build a completely new sewerage to replace the existing one. Then the existing pipes remain in the building structure, but they are taken out of use. When using this method, the new piping can be freely designed and constructed to meet the requirements, but at the same time all the wet rooms and toilets need to be renovated even though they would be flawless. This must be done because the renovation of the floor drain breaks the water insulation and thus causes a significant risk of water damage. Therefore, the water insulation of the room must be rebuild.

The publication JP-A-2004316422 discloses a method where an opening is drilled through an existing floor drain, in which a new sewerage pipe is installed. The new sewerage pipe is pasted in the thus formed opening. Figure 12 shows an arrangement where the water insulation (F) remains outside the floor drain (10). Then the moisture in the floor structure cannot pass into the floor drain (10) along the water insulation.

Summary of the Invention

The present invention is a method for renovating the sewerage of a water- insulated room, where the sewerage comprises an original floor drain and an original drain pipe, the method comprising: (i) forming an opening through the floor structure from the bottom of the original floor drain without damaging the water insulation; (ii) inserting a new water trap in the thus formed opening, which new water trap is connected from its lower part to a new drain pipe; (iii) mounting the new water trap to the opening; (iv) sealing the gap between the original floor drain and the new water trap with water-insulating paste; (v) connecting the new drain pipe to a main drain pipe thus forming a water-proof new sewerage; and (vi) plugging the original drain pipe, and where the new water trap is mounted to the formed opening mechanically. A benefit of the method according to the invention is that it causes only a minor disadvantage with a short duration to the residents. Further, the floor and walls of the wet room are left intact. Further still, the sewerage is completely rebuild.

Short Description of the Figures

The preferred embodiments of the invention are now disclosed with the help of the attached drawings where:

Figures 1 and 2 present cross-sectional views of the starting point for the present invention;

Figures 3 and 4 present cross-sectional views of examples how the opening is drilled;

Figures 5 and 6 present cross-sectional views of example situations after the new water trap and drain pipe have been installed and the sewerage has been rebuild.

Detailed Description of the Invention

According to the invention an opening is drilled through an original floor drain, where the opening has a substantially smaller diameter than the original floor drain. The opening is drilled so that the original water insulation and structure is not damaged. The opening is formed through the whole floor structure and a flanged pipe is inserted into the opening. The gap may be filled with fire-proof paste. The pipe is fastened by tightening a nut into a threaded sleeve attached to the pipe. A part having a shape of an upside-down turned bowl is fixed to the upper part of the pipe to form a new water trap. A new drain pipe pipe connecting the new water trap to the existing vertical main drain pipe is fastened to the downstairs ceiling structure. The original drain outlet in the original floor drain is plugged tight.

Occasionally it is preferred to make a new opening having a smaller diameter than the largest diameter of the existing floor drain through the original floor drain without damaging the water insulation. The opening can be formed through the floor slab or alternatively by cutting the slab and leaving enough slab structure to allow mounting by a threaded connection. Then a new opening for the bushing of the new water trap is drilled through the bottom of the opening so that the new opening has a smaller diameter than the original opening. The new water trap is mounted by using a threaded connection, as explained above, and sealed with sealant, paste or glue.

An installation is exemplified in Figure 5. Fire-proof paste may be used in the opening. The tightness of the pipe connections may be monitored by using a leak detector. If the opening is formed through the floor or ceiling structures, then a nut connection may be arranged by means of a mounting disk or by casting.

Other drain outlets may be renovated with the same method, but instead of a new floor drain a pipe or a sleeve is installed into the drilled hole.

The numbers of the figures:

1 original floor drain

2 water insulation

3 frame of the floor drain

4 cover of the floor drain

5 original drain outlet 6 opening made through the floor structure

7 opening made through the bottom of the floor drain

8 cover of the water trap

9 flange

10 new water trap

11 leak detector

12 threaded sleeve

13 nut

14 original water trap

15 mounting disk for fastening the new water trap

16 new floor drain

17 new drain pipe

18 floor tiles

19 fire-proof paste

20 gasket

21 plug for plugging the original drain outlet

22 discharge pipe of a washing machine

Figure 1 describes the starting situation where the floor drain 1 is in contact with the water insulation 2. The floor drain contains the frame 3 and the cover 4. The top of the floor is formed, for example, by floor tiles 18 fastened by mortar. In some cases, the floor drain 1 has been embedded into a load-bearing concrete slab. Alternatively, the load-bearing concrete slab may be covered by an optional insulation layer, further covered by a top layer, in which the floor drain is embedded. In case of smaller houses, the floor drain may also be in a wooden floor structure. Then the top layer of the floor structure is typically made of board, and the water insulation and the floor tiles have been fastened into the top surface of the board. In addition, a discharge pipe 22 of a washing machine is connected to the floor drain. The original drain outlet 5 of the floor drain 1 is typically nearly horizontal in the floor structure, being slightly tilted towards the main sewerage pipe. The floor drain typically comprises a water trap 14, which has a purpose of maintaining a sufficient amount of water in the floor drain.

Figure 2 shows a different starting position where the floor drain 1 , water insulation 2, the frame of the floor drain 3, the cover 4, the original drain outlet 5 and the floor tiles 18 are as shown in Figure 1. In this case the discharge pipe 22 of the washing machine is not present.

Figure 3 describes the procedure for the renovation of the sewerage of the floor drain. The cover of the floor drain is removed and a vertical or at least

substantially vertical opening is formed through the floor drain 1 to the shaded area 6, which extends through the whole floor structure. At the same time the original water trap is removed.

Figure 4 shows an alternative method. Then an opening, with a diameter which is smaller than the largest diameter of the floor drain, is formed by drilling, so that the water insulation 2 is not damaged. Alternatively, the opening can be made by cutting so that its diameter is smaller than the largest diameter of the floor drain. A part of the floor structure is left for mounting and tightening the new water trap. For instance, drilling a hole having a diameter of 10 to 20 cm in a load-beating concrete slab is a fast and routine process by using a diamond drill. In an embodiment the hole can be formed by drilling multiple small holes and/or by using a spike.

Figure 5 shows the situation after the renovation where a vertical new water trap 10 has been installed in the original floor drain 1. The water trap 10 has been mounted to the bottom of the floor drain by using a flange 9. The flange 9 can be either fixed or movable. The water trap 10 is mounted so that the distance of the cover 8 from the bottom of the floor drain is within a desired range. The gasket 20 ensures that water cannot penetrate from the joint between the floor drain 1 and the water trap 10 into the building structure.

The gap between the water trap 10 and the wall structure is preferably sealed by using fire-proof paste 19, thereby preventing possible fire from propagating from one store to another.

A leak detector 11 has been attached to the water trap 10 for detecting a possible leak. The leak detector 11 has been mounted by using a threaded sleeve 12 and a nut 13 to form a tight and compact unit. The leak detector 11 has been tightened against the ceiling by using the gasket 20.

A new drain pipe 17 is connected to the drain output of the new water trap 10, which leads the water to the main drain pipe. The main drain pipe is typically a vertical pipe to which the drain pipes from all the stores are connected. The new drain pipe 17 is in a space below the renovated space, for instance, in a corresponding downstairs space in an apartment building, or in a cellar.

Preferably the new drain pipe is attached to the ceiling of the downstairs apartment by using brackets. The pipe is insulated and a new, lowered ceiling is build below the pipe. The pipe is thus hidden from sight.

The original drain outlet 5 of the original floor drain is plugged with a plug 21.

If the original main drain pipe was installed in a duct it is preferred and

environmentally friendly to leave the original piping in place and build the new vertical pipeline in a suitable space. The pipes are soundproofed and

encapsulated in factory-made casings. Then massive demolition work and possible exposure to asbestos can be avoided. The visible original drain pipes, for instance in cellar space, can be removed and replaced with new ones.

The new water trap 10 and the new drain pipe 17 are preferably made of non- oxidizing material, such as stainless steel, aluminium, brass or plastics, such as polypropylene.

Figure 6 shows a situation where a new floor drain 16 has been installed inside of the original floor drain 1.

The new floor drain 16 is sealed into the opening by using fire-proof and waterproof paste 19, for instance waterproofing paste or preferably epoxy-containing resin or epoxy resin which cures after it has been applied in its place by brushing, extruding, or other suitable means. After the installation the water insulation remains intact from the new floor drain through the entire floor area and the floor tiles need not to be removed. The join of the new floor drain is ready and the original floor drain cover 4 can be reinstalled and the renovated wet room looks the same as it was before the renovation. It is often beneficial that the new floor drain has such dimensions that the new floor drain is supported by the floor, the bottom or both the floor and the bottom of the original floor drain.

Figure 6 shows that the edge of the water insulation 2 remains outside the new floor drain 16 in the original floor drain 1. However, it is beneficial to install the new floor drain 16 so that the edge of the water insulation 2 extends inside the new floor drain. Alternatively, the upper edge of the new floor drain 16 is lower than the upper edge of the original floor drain 1 and the water is arranged to flow from the upper edge of the original floor drain to the new floor drain 16.

Water is led from the new floor drain to the main drain pipe, which is typically vertical and to which the drain pipes from all the stores are connected, along the new drain pipe 17, which is connected to the drain outlet of the new water trap 10. This new drain pipe is installed in a space below the renovated space, for instance, in a corresponding downstairs space in an apartment building, or in a cellar. Preferably, the new drain pipe is attached to the ceiling of the downstairs apartment by using brackets. The pipe is insulated and a new, lowered ceiling is build below the pipe. The pipe is thus hidden from sight.

The water trap 10 is in this case fixed to the floor structure by using a mounting disk 15. The leak detector 11 can be attached to the mounting disk 15 for detecting possible leaks and for sealing the structure. The water trap 10 is tightened against the mounting disk 15 by using the nut 13.

It is possible to fill the gap with fire-proof paste 19 for improving the fire safety.

If the original main drain pipe was installed in a duct it is preferred and

environmentally friendly to leave the original piping in place and build the new vertical pipeline in a suitable space. The pipes are soundproofed and

encapsulated in factory-made casings. Then massive demolition work and possible exposure to asbestos can be avoided. The visible original drain pipes, for instance in cellar space, can be removed and replaced with new ones.

The other possible drain outlets, such as those of washbasins and toilets, in wet S

rooms and also other rooms, can be renovated accordingly. An opening is formed from the existing outlet, for instance, by drilling through the floor structure without damaging the water insulation. In this case a pipe or a sleeve is mounted in the opening which, if needed, is sealed to the original water insulation. The said pipe or sleeve is connected to the main drain pipe with a new drain pipe in the space below the floor structure.

By using the above-mentioned method the drain pipes of the wet rooms and, if needed, of the whole apartment can be renovated without damaging the original water insulation and the floor tiles. A!so, other modifications are small and inexpensive. In addition, the renovation can be done quickly and the residents do not need to move during the renovation to a temporary residence.

Another advantage of the invention is that when the floor drain or the water trap are renovated according to the invention, the water is led from the floor of the wet room to the floor drain and cannot accumulate. The original water insulation is left intact. The maintenance is also easy: for instance, if needed, the water trap can be replaced by a new one without touching the remaining structure.

When the new water trap is mounted by using a movable flange, the water level in the floor drain can be adjusted, if needed, by changing the height to which the water trap extends from the bottom of the floor drain.

The method according to the invention can be used for renovating floor drains of all forms. The location of the floor drain is not limiting, either. If the bottom of the floor drain is not smooth, it can be smoothened by using, for instance, a suitable paste.

A further advantage of the invention is that the existing structure needs not be demolished. This avoids a money- and time-consuming demolition step. The method is useful especially, if the original structure includes asbestos, because asbestos demolition work is not needed.

When using the method according to the invention the upstairs and downstairs floors can be insulated as separate compartments by plugging the opening with fire-proof paste. In addition, the leak detector may be used to insulate the opening made for the new water trap or the new floor drain from the downstairs compartment.

In the method according to the invention the new water trap of floor drain is preferably supported by existing floor or wall structures, or the floor and wall structures of the original floor drain. New support structure is not needed. This helps saving time and expenses.

The method according to the invention uses preferably mechanical fastening, such as by flange or screw. Also, the plugs are preferably mechanical, for example rubber plugs, and they are suitably fastened by screws and nuts. This makes the new structure easy to maintain and replace.

The new water trap used in the method according to the invention is substantially vertical, making it easy to mount to the vertical opening. The water trap comprises a pipe whose upper end comprises a generally cylindrical dome with a solid upper end. The diameter of the dome is greater than the diameter of the pipe so that a channel forms between the outer surface of the pipe and the inner surface of the dome, along which water can flow into the pipe. By manipulating the height of the dome from the bottom of the floor drain the water level in the floor drain can be adjusted. The floor drain is mounted to the structure

mechanically, for instance by a flange or a thread connection. A movable flange is especially preferred because then the height of the dome can be easily controlled. The leak detector used in the method according to the present invention comprises advantageously an annular disk or plate which is mounted around the external surface of the water trap. The inner surface of the disk settles tightly against the external surface of the water trap. The disk or plate comprises a groove with a width of about 5 mm adjacent to the external surface of the pipe, so that water possibly leaking from the water trap collects into the groove. A moisture analyser is in contact with the groove giving an alarm if water collets in the groove. If the new water trap or its drain pipe is lead through the ceiling structure, then it is often advantageous to tighten the leak detector around the water trap or its drain pipe against the ceiling structure, as shown in Figure 5. Then the leak detector contributes in insulating the upstairs space from the downstairs space and an additional insulation is not necessary.

The person skilled in the art understands that when the related technology develops further the principal idea of the invention can be reduced to practise in a number of ways. The invention and the related embodiments are not limited to the examples described above but can vary within the scope of the claims.