After builders cleaning in Pinner, HA5

Harrow's appraisal calls Pinner High Street a remarkable survival of a medieval village. The market was granted in 1336, the oldest houses (judging by their crown post roofs) are at 25-27, 33-35 and 4-6 High Street from the late fifteenth or very early sixteenth century, and the conservation area holds 26 listed buildings and 6 locally listed ones. It carries an Article 4 direction. Within 800 m of the middle of Pinner ward there are five more conservation areas (Waxwell Lane, Waxwell Close, Moss Lane, East End Farm and Tookes Green) and 47 listed buildings, four of them Grade II*.

A timber-framed house after building work needs a slower clean. Dust sits along the beams, in the joints of old panelling and on uneven boards, and the crew lifts it with a dry cloth and a vacuum before anything damp goes near the timber. Old glass and leaded lights are wiped by hand. Anything that looks loose or fragile is left alone and pointed out on the walk-round, and the crew does not wash walls or scrub old plaster.

Harrow charges £241 for a scaffolding licence for the first month, covering up to 10 metres of frontage, and £191 for every month after, plus a £759 refundable deposit for up to 15 metres and £135 if a highway officer has to meet on site. On some jobs the scaffold stays up for a while after the works are finished.

The crew can clean inside while the scaffold is still standing, as long as every trade, roofers included, has finished. The outside of the glass waits until the scaffold is down, because the crew only cleans exterior windows it can reach safely from inside or from the ground; outside window cleaning is priced by house size.