Gully question

[roblatus]

We are going to be having a small extension built to the rear of our property. We currently have a gully that the kitchen sink and washing machine drain into that will be inside the new extension. What would be the best way of leaving this gully with an inspection point/cover as it is going to be staying where it is. Ideally something that would be flush with the surrounding concrete floor would be excellent. I then intend to laminate over it.

Thanks in advance for any help/suggestions.

 

[HERTS P&D]

I then intend to laminate over it.

Don't laminate over it, when it blocks (which it will do) how are you going to clear it???

You will only know its block when the laminate is soaked with water.

Andy

 

[TicklyT]

The existing gulley will have to go, unless you particularly enjoy the fragrant perfume of Eau de Drain. No doubt your BCO and Environmental Health will say the same.

Sealing the existing pipes into the top of the existing gulley would leave the gulley trap inaccessible if, or more likely, when it gets blocked.

There's little purpose in fitting an internal inspection /rodding access point, and then making it inaccessible by covering it with laminate flooring.

That leaves the options of creating a new stub stack where it's needed, say, under the kitchen sink, or extending the waste pipes through the extension to a new external gulley.

 

[roblatus]

Could the existing gully be moved under the kitchen sink? Someone mentioned using something called a Hepworth Access manifold to me, i have no idea what one of these is tbh lol. One builder has indicated that the gully could be left where it is but one of these manifolds used??

If the gully is moved under the kitchen sink whats the difference between that and just leaving it in the extension in the first place?

Not sure if moving it out of the extension will be an option. The drain runs along the the back of the house and all of the new extension will be built over it. I have already had a camera survey done as advised by the people who drew our plans, and the drain is sound.

 

[TicklyT]

The top of a gulley is open to the atmosphere, and has a water trap at the base to stop sewer gases escaping. These trap, like all traps, are prone to blockages.

Sealing the top of a gulley is a nono. it traps a plug of air in the wastes between the sink and gulley traps, leading to unpredictable performance, slow draining and/or drawing of the water seal in the attached wastes.

A stub stack is just a pipe turned up through the floor, with the end plugged. The waste(s) are sealed into the sides or the end plug. There is no trap at the base of a stub stack, the pipe is (or should be) 'dry' when no waste is flowing, and vented via your soil vent pipe. The sink waste and appliance traps provide the seal. It is usually arranged so a plug in the side or end can be removed for inspection or rodding access.

Siting one, say, under the sink puts it in an inconspicuous place, does away with a selection of sink and appliance waste pipes penetrating the wall, and will still be accesible, even after laying your flooring.