Exterior car detailing across Hertfordshire

Town by town

What is bonded to the paint in each part of the county

Hatfield, Welwyn and the A1(M)

Iron. The towns along the motorway collect brake dust from it every day, and it lands on paint and alloys as particles that rust in place: orange specks on a white car, a brown shadow on the wheels that no brush shifts. The iron remover in the decontamination turns purple as it dissolves them. Hatfield's long stay car parks at the university add a term's worth of everything else.

St Albans and Harpenden

Honeydew and tar. The limes on the avenues drip through the summer and the sugar bakes into rings; the M1 and the A1081 throw tar onto the sills. The clay lifts the first and the tar remover dissolves the second, and on the county's newest cars this is the detail that keeps a lease car's paint honest to the end.

Letchworth, Hitchin and Baldock

Sap and chalk. The first garden city's trees are a century old and the Chiltern lanes out of Hitchin are white in a dry week; together they put a film on the paint that feels like fine sandpaper after a wash. The decontamination and clay take it back to smooth, and the wax means next summer's film rinses off.

Hertford and Ware

Salt and river. The Lea keeps a parked car damp all winter, the A10 adds spray, and salt on wet paint for months is what dulls it. The detail in April lifts the winter off; the wax afterwards means the next one beads away.

Knebworth and the lanes

Oak sap, mud and the occasional hedge. The sap hardens into lacquer under the village oaks and the clay is what lifts it; the restored plastics and the wax are what make a five year old estate car look sold. Hedge scratches are a correction, not a detail, and your washer will tell you which you need.

Across the county

Two seasons for a detail, and a dry day for either

Hertfordshire salts about 1,500 miles of priority roads from October to the end of April, which gives the detail its calendar. April, when a winter of salt, iron and tar has bonded to the paint and needs lifting before the summer; September, when the summer's sap, chalk and honeydew come off before the salt returns. For a car worth keeping for years the September detail is the preparation for a ceramic coating; for a car going on sale, the detail the week before the photographs is the cheapest thing you will do to its price.

The booking takes a minute: the postcode, which the page checks against the Network's coverage, then the Exterior Detail and a window. With the clocks gone back on 25 October the 10am window is the sensible one, because the washer needs two to three hours of daylight on a family car. A drive is best; a kerb space or a bay is fine so long as there is room all the way round. The one thing the day has to be is dry, or the wax will not bond, and the washer will move a booking rather than wax wet paint. Water and power arrive in the washer's van. The order on the day is wash, iron and tar removers, clay, wheels, plastics, windscreen, wax, and the before and after photographs land with the receipt.

The details we do across Hertfordshire

• A Hatfield commuter with brown wheels: Exterior Detail; the iron remover does what scrubbing cannot.
• A Harpenden car with honeydew rings after a summer under the limes: Exterior Detail, then a wax to stop next year's.
• A Hitchin car that feels like sandpaper after a wash: Exterior Detail for the chalk and sap film.
• A Hertford car after a wet winter: Exterior Detail in April, wax on for the summer.
• A village estate car with oak sap lacquered on: Exterior Detail, the clay lifts it.
• A car going on sale in St Albans: Exterior Detail the week before the photographs.

More on this: exterior detailing in Stevenage and ceramic coating across Hertfordshire.