As Duffman said there can be varying degrees of what builder's finish is.
Last year I was involved with a house build project which came in at €95/sqft.
This year we are just finishing a house which is coming in at €168/sqft fully finished. There a lot of factors which can govern the cost per sqft measure. House designs which move away from 4 square walls and incorporate more angles and wall joins, this has significant impacts throughout the build. Difficult ground and large amounts of excavation work. Through in heat pumps, hi spec bathrooms and kitchen and finishes into the mix and your developer's standard 100/sqft is well left behind.
As an example take a look at this breakdown and see where costs can go north.
Fees: Legal/Surveyor/Engineer/QS/ € 7,000
Site Foreman € 19,000
Insurances € 3,200
ESB € 1,800
Well € 3,000
Waste Treatment unit € 3,500
Plant & tool hire, scaffolding,container,security fencing, + misc € 13,000
Groundworks (Excavation, removal, trenching, plant) € 27,000
Foundations to finished slab € 27,000
Timberframe € 58,000
Labour
- Blocklaying € 4,500
- Stonework € 7,700
- Slating & roof leadwork € 4,500
- Cedar cladding, soffit & fascia € 7,000
- General labour € 5,500
- Fermacell boarding € 8,000
- Fermacell finishing (excludes a load of work I did on this) € 4,000
- Ceiling skim € 2,500
- External plastering € 3,000
- Tiling € 12,000
- Floor levelling € 4,000
- Carpentry € 3,200
- Painting € 3,500
- Ext. works (retaining wall, fencing, ...) € 5,000
GS Heat Pump, UFH, 500L cyl with own heat pump € 20,000
Plumber € 8,000
4 Bathrooms fit out € 15,500
Electrical & lights € 11,400
Material Costs
- Windows & ext doors € 40,000
- Internal doors € 5,800
- Slates, Cedar, Stone, cills, misc building supplies external € 38,700
- Insulation € 7,000
- Internal doors, arch, skirting € 5,700
- Fermacell € 7,000
- Central vac € 1,200
- Kitchen € 37,500
- Inset stove € 1,600
- Tiles € 10,000
- Wood floors (supply & fit) € 7,600
TOTAL €453,900
Size 2700 sqft (€168/sqft)
Take out Kitchen, tiles, floors, bathroom fittings ... it is more like 137/sqft.
AndyH