12 week old Silkies and cold

[SaltySparrows]

Lowest this week will be 33, with highs in the 60's. Do they still need a heat lamp at this point in the coop?

 

[ChickensAreSweet]

Assuming they are out of the wind, they can have the heat lamp turned off at 6 weeks of age (if brooding in cold temps I give them until 8 weeks usually). As long as they are fully feathered and in a nice non-drafty coop they will be fine.