Laying patio over existing cobble lock?

[quenching]

Could I ask some stupid questions please, ones which I'm getting varying answers to from different stone suppliers and installers, all of which are adding confusion to what I thought would be a simple project! Drawing here:

Diagram

I need to have a new patio installed to replace an existing wooden deck. The deck adjoins the house at floor level so you can walk straight out onto it, 13 years old so needs repair or replacement. Under the deck is mostly soil, with a small area of old cobblelock brick paving and a small concrete perimeter path (45cm wide) around the edge of the house, path and cobblelock brick paving installed when house was built 20 years ago.

1. Does the cobblelock paving need to be removed before laying the new patio?
2. Does the perimeter concrete path need to be removed before laying the new paving?
3. I know the new paving should be 150mm below the DPC but can anyone tell where the DPC is from this photo?
DPC Photo
4. I'm thinking of a yellow/buff coloured granite, limestone, or sandstone. Given that I'm happy to have it sealed (or not) and pressure wash it twice a year, are any of these NOT suitable for Dublin.

Please be gentle with your answers :laugh:

[seanandruby]

I think you could say at 20 years old that your existing concrete is 2 below dpc. Are there any air vents to confirm height? Yes take out existing paving before laying new. Glad your getting rid of that decking quench. Only problem i can see with it being Dublin is if you spill any guinness on the new flags :;):

[Tony McC]

As Sean says, get rid of all the old cobble lock (Irish for 'block paving') and concrete, then get a proper sub0base and your chosen flagstone laid as shown on the main website.

Can't say with any certainty just where the DPC is in your photie, but, my experience with Irish building techniques suggests it's *probably* 150mm below the render rail. It *should* be coincident (ish) with internal floor level.

Depending on where you are in Dublin, Tobermore Paving Centre up near Swords, Timmy Tuohy's Natural Stone Yard in Ashbourne, or Balgriffin Patio Centre in Malahide are usually good with advice, and the same with Cabinteely Patioo Centre on the south side.

[quenching]

Thank you both for your advice, its very much appreciated, the old brick paving shall be removed and the new paving below the DPC. I've had 2 similar quotes for the work so now it just depends on stone type and references.