A long elevation (Dutch: langsgevel) is the long side of a rectangular building, running parallel to the ridge. With a pitched roof it is also the eaves elevation, because the gutter and the wall plate sit along it. Its counterpart is the gable end, at right angles to the ridge, which carries the gable in a pitched roof.
Structural role
- It carries the wall plate. The wall plate on which the rafters or frames land sits on the long elevation; through the purlins a large share of the roof load ends up on this wall.
- It sets the eaves height. The height of the long elevation fixes the eaves height — a dimension almost always regulated explicitly in a development plan.
- It provides stability. The long elevations take the wind that pushes on the gable ends, and vice versa. A building with two long, largely solid elevations is stable in the length direction without further measures.
Application
In farmhouses the choice of access side determines the type: put all the entrances in the long elevation and you have a long-facade farmhouse. In terraced housing the long elevations are the front and rear walls, while the gable ends are the party walls.
Points to watch
- Large openings cost stability. Opening a long elevation up with wide glazed screens removes exactly the plane that carries wind load off the gables. The remaining piers between the openings then have to take those forces. Have it checked; “there’s a lintel over it anyway” is not an answer.
- Lintel and bearing. Above a new opening sits not only masonry but often the wall plate carrying the whole roof load. The bearing of the lintel is then at least as critical as the lintel itself.
- Eaves height is a planning matter. Raising the long elevation for a roof extension or an added storey almost always runs into the maximum eaves height.
- Driving rain. The long elevation facing the prevailing wind (south-west in north-west Europe) receives the most driving rain. Pointing, window junctions and the open perpends at the base of the cavity deserve extra attention there.
Related terms
- Gable end
- Facade
- Ridge
- Wall plate
- Pitched roof
- Long-facade farmhouse
- Perpend
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