Laws pertaining to construction topics, whether commercial or residential, are designed to regulate the industry, to protect buyers and sellers, residents or the public, to levy penalties for non-compliance and malfeasance, and to provide a means for dispute resolution.
The body of law is extensive and complex. A legal specialty in construction law can be broadly inclusive, or may focus on one area of expertise. A construction attorney must be familiar with the broad foundation, but most choose to limit their practice to only a few areas.

Contract Law:

Over the years, several standardized forms of contracts have been developed, and although there are similarities, the distinctive language of each contract is a vital consideration to protect the interests of the individual parties involved. Contract law in general pertains to many other fields, but construction contracts are often much more comprehensive and detailed, and sometimes contain unique provisions. Most contracts today contain some sort of mandatory mediation clause, but contract disputes are common and contract resolutions is one of the primary popular specializations for construction attorneys.

Dispute Resolution and Litigation:

Construction law is practical, and a prime goal of dispute resolution is to settle a dispute as quickly as possible; cases are frequently settled out of court. However, attorneys must be confident litigators as well as effective negotiators. Dispute resolution requires diligent fact-finding efforts and preparation, drawing upon all the training and experience that a legal team can muster.

Torts:

Claims resulting from personal injury on a jobsite or from material and equipment failure are common and frequent. They are often speedily addressed and resolved quickly for the benefit of both the business and the injured party. But not always.

OSHA and Workers Compensation:

Related to torts are other types of claims arising from OSHA requirements and the Workers Compensation laws of various states. Attorneys who specialize in these areas are concerned with adherence to existing law, but also with the prevention of unintended violations that result from periodic changes to existing law. Both require diligence and compliance with detailed procedures.

Employment Law:

Federal, state and local guidelines regarding the workplace and how a business hires, compensates, treats and manages employees are increasingly complex and restrictive. This area of law is pertinent not only for construction companies and their staffs, but has ramifications for business dealings with subcontractors and the public as well. Fairness doctrines, equality, employment testing and separation policies also come under scrutiny.

Planning and Permitting Law:

A final area of specialty for construction attorneys involves land planning and urban development, with attorneys who represent municipal or governmental entities, and other who seek permits and approvals on behalf of developers and builders. Expertise with zoning principles, infrastructure, historic preservation and land use, reclamation and preservation are sometimes necessary.
Eminent domain proposals, which allow the taking of private land for public use under certain circumstances, can be hotly contested and requires additional expertise.
The broad field of construction law and its unique specialties may come into play in any given situation. Diversity is part of its appeal: From liens and defects to future planning and deeds and ownership transfers, there is ample room for all sorts of specialties.

Source:
http://legalcareerpath.com/what-is-construction-law/
https://hirealawyer.findlaw.com/choosing-the-right-lawyer/construction-law.html