Please guys í and hubby av dis 4 bedrooms to roof, we planned to use slate but hubby is saying is kind of old versión dt he wants aluminium step tiles

From d carpenter estimate he said we are to use 170slates ,í want to knw ow many step tiles we wil use dt Will equivalent to 170slates

Secondly, most we do paravet (dunno if dt spelling is correct) if we want to use step tiles

Pls í nid urgent answer cos am meeting with the material seller today and all d money for the roofing is already wit him b4 hubby change mind to step tiles. TIA

Your write ups are conflicting, kindly call to get a professional advice on ur building needs.