The local spatial management plan, adopted in Poland at the level of the municipality, is a source of universally binding law, determines the purpose of the area, the distribution of public purpose investments and defines the ways of development and the conditions for land development. The local plan is the basis for issuing the building permit decision on the areas for which its arrangements apply. It directly interferes with the rights vested in entities in real property and property rights. The provisions of the plan, as an act of universally binding law, bind everyone, including all administrative bodies and courts, as well as property owners. When adopting a local spatial management plan, the commune council should be guided by a number of values, including maintaining spatial order, architectural and landscape values, as well as environmental protection requirements. A local plan is an act of local law, therefore it must contain standards defining the specific purpose of each area covered by the regulation in an unambiguous manner, it cannot contain provisions that make land development conditional on subsequent opinions of public administration authorities or allow any entities to individually agree on deviations from the adopted plan. In practice, however, the ambiguity of provisions regarding environmental protection is noticed, in particular in the interpretation of the concept of biologically active land. The work presents how significantly this problem affects the construction investment.