This study provides an alternative empirical approach to identify optimal urban growth when accounting for its associated environmental effects. It is assumed that preserving outer landscapes and enjoying reduced density levels are inversely related, and so households must trade them off. The exercise analyses whether more disperse urban growth would be socially desirable in a particular area, the metropolitan region of Barcelona. A contingent valuation exercise using a double-bounded format was undertaken and an extended version of the spike model was used to estimate the willingness to pay of changing to a less dense urban path. The results show that a less compact scenario would be welfare-increasing in aggregate terms. It is suggested that general proposals on compacting cities should not necessarily constitute a desirable planning goal.