Tanked cellar

[SUNRAY]

We are being tasked with the wiring while a Tanked cellar is being re-tanked and refurbished.

Basically the studwork for the walls has rotted and some blame is being placed on the existing wiring touching the tanked surface and allowing moisture to bridge the gap...

Realistically it is just hanging in the void so may very well be guilty to some extent.

My suggestion is running plastic conduit on the new studs before the plasterboard is fitted and plasterboard back boxes.

Any better ideas?

 

[333rocky333]

We done some work in the cellar of a listed building, Number 1 London, a specialist firm glued surface wooden blocks on, then we screwed saddles and accessories on to them and used surface galv conduit.
May look a bit ugly (or even trendy) in someones house.

 

[SUNRAY]

We done some work in the cellar of a listed building, Number 1 London, a specialist firm glued surface wooden blocks on, then we screwed saddles and accessories on to them and used surface galv conduit.
May look a bit ugly (or even trendy) in someones house.

Did it stay in place and not rot? I have seen this method before but all the fixings had failed so fittings were hanging loose. It was a good number of years after installation.

This job is a very uneven flint wall and will be drylined and ventilated with nothing touching the walls and all services hidden.

 

[bernardgreen]

touching the tanked surface and allowing moisture to bridge the gap.

I may be missing something but where did the moisture come from....?

If it was ( is ) coming through the tanked wall then the tanking has failed and needs to be redone with impervious lining(s).

If it is condensation from water vapour in the air in the cellar then ventilation needs to be improved.

 

[SUNRAY]

I may be missing something but where did the moisture come from....?

If it was ( is ) coming through the tanked wall then the tanking has failed and needs to be redone with impervious lining(s).

If it is condensation from water vapour in the air in the cellar then ventilation needs to be improved.

I don't know but I suspect the rough flint wall was difficult to seal, however that is not our remit and it is being retanked.
The rotted lining was mounted snuggly between the floor and ceiling so effectively sealed, the replacement wall will be fitted with a gap at floor level and finish inside the new plenham ceiling to provide the ventilation. Nothing is to touch the flint wall, the only thing that could before was the loose fitted cables, hence the initial reference in the report.
Our remit is only the leccy and I'm looking for others thoughts on best practice.

Edited to correct auto correct.

 

[flameport]

looking for others thoughts on best practice.

Nothing is attached to the tanking at all, or even allowed to be in contact with it,
If items really have to be fixed to the tanked walls, those installing the tanking do the fixings for them.
Also keep good records including photos of exactly what was installed where, how and by who.

When these installations fail, the finger of blame will be pointed somewhere - make sure it isn't you.

 

[SUNRAY]

I don't know but I suspect the rough flint wall was difficult to deal, however that is not our remit and it is being retanked.
The rotted lining was mounted snuggly between the floor and ceiling so effectively sealed, the replacement wall will be fitted with a gap at floor level and finish inside the new plenham ceiling to provide the ventilation. Nothing is to touch the flint wall, the only thing that could before was the loose fitted cables, hence the initial reference in the report.
Our remit is only the leccy and I'm looking for others thoughts on best practice.

Nothing is attached to the tanking at all, or even allowed to be in contact with it,
If items really have to be fixed to the tanked walls, those installing the tanking do the fixings for them.
Also keep good records including photos of exactly what was installed where, how and by who.

When these installations fail, the finger of blame will be pointed somewhere - make sure it isn't you.

No nothing will touch the tanking at all, I have seen situations before where fixings have been drilled through the tanking and the water then drips from the fixed item.
The lining wall will be 4x2 timber and plasterboard, fixed only top and bottom. My thought is to fix plastic conduit to the studs which could help with any future alterations but this is surely not a rare situation and I wondered if others had a better idea.

 

[SUNRAY]

Thanks, I've received a PM suggesting using metal saddles for the conduit as the plastic versions can get brittle.

 

[bernardgreen]

With vertical conduit in the cold area between tanked wall and stud wall condensation in the conduit has to be considered.

The cold area cools air in the conduit and convection currents occur. In worse case situations drain holes at the bottom of the vertical conduit runs may be necessary

 

[SUNRAY]

I was thinking more about leaving the bottom of the tube open but that's a good point you've raised, any condensation in the tube would drip onto the bottom rail of the studwork.

Originally we were going to clip cables down the studs but I like the idea of the tube for future alterations/repairs.

 

[SUNRAY]

With vertical conduit in the cold area between tanked wall and stud wall condensation in the conduit has to be considered.

The cold area cools air in the conduit and convection currents occur. In worse case situations drain holes at the bottom of the vertical conduit runs may be necessaryView attachment 150837

Would pipe lagging be an idea?

 

[bernardgreen]

A friend living in a converted water mill tanked his cellar but included a gully around the room to catch any water from the wall ( leakage and condensation ) and take it to a sump from where it is pumped out.

 

[bernardgreen]

Would pipe lagging be an idea?

Lagging would reduce the effect but not eliminate it.

 

[SUNRAY]

A friend living in a converted water mill tanked his cellar but included a gully around the room to catch any water from the wall ( leakage and condensation ) and take it to a sump from where it is pumped out.

'They're' still debating about the pumped gulley, We're putting the circuit in regardless as it'll be minimal cost but a huge PITA to do it later.

 

[JohnW2]

A friend living in a converted water mill tanked his cellar but included a gully around the room to catch any water from the wall ( leakage and condensation ) and take it to a sump from where it is pumped out.

My (untanked) cellar is similar - a network of drainage pipes under the floor which take water to a sump from where it is pumped out. It usually works fine (which rather surprises me, since the floor is usually/often below the water table!), but I still occasionally need my wellies on down there after prolonged heavy rainfall!

Kind Regards, John