In Heathrow and Harmondsworth (TW6) the split is 42% flats to 58% houses over 3,318 households, and the stock is post-war.
With 42% private renting against 41% owner-occupied, most TW6 bookings land on a move-in day rather than a weekend.
Heathrow and Harmondsworth substrates run to cavity brickwork outside — and timber stud partitions inside, which is what a 42% flat share across the ONS neighbourhood covering Heathrow and Harmondsworth actually produces. Nothing is drilled until the wall has been sounded, because a four-hole bracket with two screws in a stud and two in fresh air, as the Heathrow and Harmondsworth stock goes, the reality on the streets around Harmondsworth Great Barn is the mistake that costs a TW6 customer twice.
Heathrow and Harmondsworth is outside the Congestion Charge zone but inside ULEZ; our vehicles are compliant, so nothing is added for it. What shapes the job more is the neighbourhood itself — the airport itself plus the villages of Harmondsworth, Sipson and Longford beside it — which is why a TW6 quote is not a Hillingdon average.
On access, airport perimeter security, restricted vehicle zones and drop-off charges; the villages are quiet with driveways — one reason four crew and a supervisor on a standard floor clearance, scaled up for phased overnight work. Fitters travelling in use Heathrow Terminals 2 & 3 (Elizabeth line, Piccadilly).