Do Zerg buildings heal automatically during the Heart of the Swarm campaign?

When playing the last mission of the campaign my Hive was attacked by some flyers, and was reduced to red. I finished off the attackers and thought my buildings would heal back up, but when the next attack came in a few minutes later my building was still bleeding and in red. It just barely survived this time, so I parked a queen next to it for some healing, but when the next attack came in it didn't look like it had healed at all, and the queen had 100+ energy. Manually transfusing the building seemed to work, but it would take a ton of queens to make this viable, so I think I must be missing something.

Do Zerg buildings heal? Is there a way to make a queen auto-transfuse a building, in case I want to park one next to my Hive?

Solution 1:

Yes, Zerg buildings heal at a rate of 0.27 points per game second, the same speed as Zerg units.1

In practice, this means that you'll have to defend a damaged building for quite a long time before it recovers, an in-game minute is worth about 16 health. Queens will not autoheal buildings other that defensive structures. (spore/spine crawlers)

Solution 2:

All zerg buildings heal http://sc2armory.com/game/zerg/. They heal at the same rate as normal zerg units which is slow. Queens cannot transfuse buildings in HOTS campaign nor can they spawn larva (personally I don't know why, those are good multiplayer skills)

Note that zerg buildings heal while on creep, but lose health while off creep. Their slow heal rate is in a way a weakness versus terran or protoss. Terran can repair buildings with great speed. While protoss shields regen faster than zerg hp, but protoss cannot repair. Though as another tip terran scvs can repair protoss units.