How to fill a hole "upwards"

[rdn123]

I have an old coal hole underneath the pavement in front of my house. It is structurally sound, but the chute where the coal used to be delivered has not been sealed up. If I look up it, I can see the underside of the paving stone in the pavement.

My problem is rainwater flows around this pavement stone, and down the chute. I'd like to use this coal cellar for mostly-dry storage.

I can only access the chute from below. It is about 16 inches tall, perfectly vertical. How do I go about filling it up? I'd like to (mostly) stop the water ingress, so one of the water-proof "tanking" cements sounds like a good idea, but gravity is against me.

How do I go about cementing/mortaring/grouting/filling....upwards?

 

[JohnD]

I can think of no method that would be half as easy as lifting the paving slab. Why don't you want to do that?

 

[kbdiy]

If by pavement you mean the public footpath then clearly you cannot attack from above as that is the council's responsibility.

However I also cannot think of a way you can successfully seal this from below. To make an effective seal the area surrounding the chute would need tanking and sealing from surrounding ground water runoff which will be almost impossible if in the public footway.

 

[footprints]

Not perfect, but I would cut a bit of sturdy ply to the size of the chute butter it liberally with water resistant mortar and push it up into place then wedge a bit of timber as a temp "Acro prop" to hold it in place till it sets. Maybe leave the timber in and fit a couple of battens each side to give it extra support.

 

[rdn123]

Yes, sorry I wasn't more specific, but kbdiy is correct: I meant the public footpath when I said the pavement. I don't think the council would appreciate me lifting the stone!

I will try out a heavy buttering of cement on a hole-shaped board. I might end up doing it in layers like a beautiful cement wedding cake to mostly fill up the hole.

I also don't want the hole to be re-opened if the council ever re-lay the paving slabs!

 

[footprints]

Yes, sorry I wasn't more specific, but kbdiy is correct: I meant the public footpath when I said the pavement. I don't think the council would appreciate me lifting the stone!

I will try out a heavy buttering of cement on a hole-shaped board. I might end up doing it in layers like a beautiful cement wedding cake to mostly fill up the hole.

I also don't want the hole to be re-opened if the council ever re-lay the paving slabs!

Maybe get some tips from Mary Berry on BBC's Bake Off