Door step replacement - Victorian Terrace

[ladybird4]

Hello,

I'm hoping for some advice

My doorstep is crumbling and needs replacing. See image attached.
I've found a replacement that looks similar to the original but have two tradesmen with two different approaches.
A, will only cut the original step up to the point when the tread meets the riser. (Red arrow) He was concerned about removing the back of the step. Don't know why.

B, will remove the entire original step so that the step/tread goes underneath the riser into the recess.

I believe (may be wrong) that the step at each side goes inside the brickwork of the house wall as opposed to being cut around it.

Any advice would be much appreciated.

Also whatever the riser is made from/or covered in is also crumbling. Sounds hollow if I tap it. I'm assuming the loose parts need to be chipped away and re finished with something?? Preferably a sandy colour to colour match what is already there.

Any help would be much appreciated.
Thanks

 

[DAZB]

The riser will be a thinner Sandstone than the step and will be sat on the tread so just cutting up to it will weaken it to some degree. You can get resin and epoxy repair compounds now that could be used to reinstate the nosing and may be a cheaper option for you.