Hold Portal

Abjuration (Ward)
Tier: 1
Components: Verbal
Casting Time: 1 major action
Range: 120 ft
Target: One portal, up to 20 square feet/level)
Duration: 1 minute/level
Saving Throw: None
The door slams shut behind you, cutting off your pursuers. A moment later, you hear their banging on the door, but it hardly shudders.

This spell magically holds shut a door, gate, window, or shutter of wood, metal, or stone. The magic affects the portal just as if it were securely closed and normally locked.  A successful dispel magic spell can negate a hold portal spell.

For a portal affected by this spell, add 5 to the normal DC for forcing open the portal.