Pointing problem - Pointing indian sandstone

[dilbert]

I have a patio done in grey indian sandstone. There are also some steps up to the house in the same stone. Problem is that under the step is void so any pointing just falls down. Looks like the builder has used little bits of black damp proof sheet wedged between slabs to gave something for mortar to sit on. This is not very good because the edges of the slabs are bevelled so the gap gets wider as it goes down.

Any suggestions?

[mike builder/landscaper]

didnt the builder point his own work to complete the job then get payed?

[dilbert]

Yes - but after the winter gaps started to appear. He is now 'uncooperative' - i.e. doesn't return my calls.

[mike builder/landscaper]

might be easier to use a hammer and chisel and break the bond between brick and step and fill the void with a little bit of type 1 or dryish conc mix.

[lutonlagerlout]

i think dibert is talking about the overhand on the steps?
is that so dilbert?
if so you need to use some gaffer tape on the undersise then fill with strong wettish mortar,strike it and leave to dry,then remove the gaffer tape 2 days later
cheers LLL

[dilbert]

Sadly, its the whole length of the join. The enclosed bit under the step is hollow!