Swift's nest in a cramped roof space

The subject of the space required by Swifts to nest successfully is an interesting and relevant topic. Here is another example indicating just how cramped a space they will tolerate. When Tanya & Edmund Hoare,  in Lowgill, near Sedbergh, Cumbria removed the tiles from their property, they found that the space beneath had been filled with rubble, giving a very irregular steep surface.

Spaces between the roof joists filled with rubble

Nevertheless, Swifts had found their way in to a suitable concave depression in the rubble on which to build their nest. The roof joists are thought to be 3 by 2's (roughly 75mm x 50mm). On top of these would be battens ~25mm thick to support the roof tiles. Thus the average distance between the rubble and the tiles looks quite small, maybe 75mm, though doubtless there is a route through the rubble with more headroom and above the nest site itself. There seems to be no large horizontal floor area. The pictures below show the story.

A Swift nest built on a depression in the rubble

Clearing out the rubble reveals an normous potential space for nesting Swifts

After removing the rubble, the builders then built Swift nests in the spaces vacated.

On top of this Tanya & Edmund also installed Schwegler Swift bricks in the gable end of her property.

Schwegler Swift bricks installed in the gable end