From bitter experience of a London Victorian terrace house’s kitchen the efficiency of a French drain may be compromised by you rear wall only having minimal footings (and possibly no damp course)
When the rear of our house was rebuilt with foundations we just went for a concrete plinth
From bitter experience of a London Victorian terrace house’s kitchen the efficiency of a French drain may be compromised by you rear wall only having minimal footings (and possibly no damp course)
When the rear of our house was rebuilt with foundations we just went for a concrete plinth