SVP and BIG usage?

[Tipper]

I'm just beginning to refurbish 2 bathrooms in my 'new' bungalow that are side by side. So far I have stripped both out down to the concrete slab. Currently one has wc, bath, bidet and sink the other has bath and sink only. I intend to add a wc to that without and need to move some of the items to allow moving a wall to make the smaller, family bathroom, bigger than the en-suite. Moving the wall will transfer the single wc soil pipe to the other bathroom.

There is an inspection chamber directly outside. The existing wc is connected direct by a 100mm soil pipe, all other items drain via two 100mm soil pipes that are imbedded in the concrete slab. These two connections enter the system via two back inlet gulleys located somewhat randomly in the lawn but between the house and the inspection chamber. There are no other drains into the hoppers of the BIGs. There is also a separate svp connected direct to the inspection chamber.

Obviously I can't use the BIG connections for a wc (or can I?) but can I use the svp instead so as to avoid digging up all the bathroom floor as it runs under the bathroom and will still vent above roof level inboard of the bathroom?
Maybe taking out the BIGs and connecting direct could be done? It seems to me that the BIGs are not really necessary.

 

[Hugh Jaleak]

It could be feasible to use the gulley connections, provided the gulley(s) are removed. A WC must be directly connected to the drain. The gulley can be removed and the gap bridged by use of a couple of suitable connectors and a section of 4" pipe. Care must be ensure when making this connection that all pipe ends are carefully chamfered, you dont want any rough edges where material can catch causing a blockage.

The other gulley could be repositioned by the house wall for the wastes, or if you only propose to make one connection, remove the other gulley and fit a suitable cap to the redundant pipe, then seal it in concrete to prevent any possible exit by rats.

 

[Tipper]

Thanks.

I have the original 1975 design drawings and 'Hepsleve' is shown.

Is this clay or plastic?

 

[Hugh Jaleak]

Possibly even better for you then, Hepsleve is still made, it'll be 100mm vitrified clay. Available from any Builders Merchant and some bigger DIY sheds. It may, with care, be preferable to 'slot' a piece of Supersleve in to bridge the gap left by the removal of the gulley, and avoid any 'lips' in the run to the WC. It is fragile, and cut edges can be razor sharp, so take care, hower is a lot less likely to 'fall apart' as the older Salt Glazed pipes do.

If you prefer to use 110mm plastic, then the required 'rigid' connectors are available, (have a couple in the garage I think!), to connect from 100mm Hepsleve to 110mm plastic. I would think these maybe better (and cheaper) than the 'Flexseal' alternatives. Mark the plastic to correct depth for insertion of the plastic, before removing the plastic and knocking out the centre stop. (Makes it a slip coupling as i'm unsure if these are available otherwise.)

One point of note may be the connections into the existing manhole. For a gulley these are not so vital as only water is discharged, however depending on how they 'sweep' into the manhole, it may cause paper (etc) to splatter onto the benching opposite. At best this can cause an unsightly and smelly build up of waste, at worst should this build up collect then later fall off, it could potentially block the drain. Maybe worth keeping an eye on once WC is connected, if need be the benching could be built up to prevent such build up.

 

[Tipper]

Thanks again Hugh.

That all makes sense and good advice.

 

[Nige F]

What can I add to Hugh` replies just one thing in this case - check the actual diameter of the existing hepsleve against the brand new stuff - I have a feeling that they might have changed slightly back in the 70`s - I`d be pleased for Hugh to comment .

 

[Hugh Jaleak]

AFAIK Nige, the 'Supersleve' is all a standard size, but there may be a slight variation in dia between 'Supersleve' and the earlier (?) 'Hepsleve' pipes, for which I believe a suitable collar is made.

I've not yet been stumped on joining anything together, can always use a Flexseal if all else fails!

 

[Hugh Jaleak]

Have emailed Hepworth (now part of Wavin...) to clarify. Very prompt reply from Craig, the earlier 'HepSleve' range had an wall thickness of 16mm whereas the 'SuperSleve' has a thinner wall at 11mm. (100mm pipes).

The only stumbling block now is AFAIK, no rigid collar is made to connect Hepsleve directly to 110mm plastic. Tipper, you will need to either purchase HepSleve to SuperSleve collars, and use a piece of SuperSleve pipe, or a couple of Flexseals, which will adapt from HepSleve to 110mm plastic in one hit.