Iron is traditionally held as the ore of judgment or power. Thor's hammer was made completely of iron. When Thor wields his hammer of iron, the power is fearsome. If a person is characterized as iron fisted, they are powerful and dictatorial.
To dream of iron can mean a dream of being judged or sitting in judgment of others. Either way, the iron object is the power icon for whoever is in control of it.
It may also have to do with the building of a home, or thoughts about building a solid foundation with regard to career, relationships, or general perspective on life.