How are location maps updated with accurate building structures?

[ey143]

Using these online mapping software, I notice that my PD outbuilding is correctly positioned on these ordnance survey maps despite me not lodging any application etc. Even the angle is shockingly correct and accurate.

How is this achieved?

 

[charliegolf]

Satellite imagery?

 

[ey143]

Yes that is what I thought, but who the heck is minded to look at every property in the land to see if there is a marginal change in the property and also if the side of an 5x3m outbuilding is slightly skewed along the boundary wall? That's nuts.

 

[Tigercubrider]

It's done by ordinance survey.
They have a small fleet of aircraft that used to photograph every inch of the uk on fil but it's probably more digital now.

Again, these days I assume that it's largely automated and comparisons are made with existing imagery
Even if the computer just flags up new discrepancies

 

[Swwils]

In most areas it's not from aerials.

OS get automatic updates on new planning consents from the LAs, and add them to the list.

Usually someone drives out with a mapping pole and a differential GPS, generally gets 2cm accuracy horizontal and 3cm vertical.

 

[Harry Bloomfield]

In most areas it's not from aerials.

OS get automatic updates on new planning consents from the LAs, and add them to the list.

Sorry, I disagree. The OS map shows my hut, garage and workshop - there was no planning application for them, no one has been on my land measuring. The only source aerial photos.

 

[^woody^]

Every now and again you might see or hear a small light aircraft flying back and forth overhead. And now you know what it's doing.