An area of no more than 30' in any direction becomes temperature controlled for a duration of 5 years or until dispelled (30x30x30). When cast, the gem, candle and ice cube are consumed into the spell, which regulates the temperature in the room to a level specified by the caster. This zone will compensate for any temperature outside the area up to 25 degrees plus or minus the set amount before being dispelled. ie if the temperature is set to 70 degrees, outside temperatures greater than 95 degrees or lower than 45 degrees will adjust the interior temperature by the difference from that range. 

Additional features of the spell can be included during casting by adding appropriate consumed reagents:

1gp droplet of amber  - repels vermin

1gp of charcoal - prevents uncontrolled fires

1gp worth of wax - prevents smells from entering or leaving the zone

1gp worth of oil - creates light as per a lantern in the area. This light cannot be dimmed or covered as it is ambient throughout the whole area.