This is very complex area of the law and requires complete attention to the provisions of the Construction Lien Act. The Act is a complete procedural code and is often misunderstood by practitioners and the public. It is generally not cost effective where the amounts in question are not significant as the costs in prosecuting the claim for lien are quite expensive. Contrary to popular belief a Lien must be perfected after it is preserved within strict time periods. The liens validity is lost if the lien claimant fails to perfect their lien within the time limits imposed by the Act. Once the lien becomes invalid it generally cannot be revived, although a personal action is still permitted. It is important for suppliers of materials, labour or other services to first determine if they can lien and whether their provision of "services " falls within the Acts definition. Once a determination is made, the other important consideration is the timeliness of the lien . One must establish that the lien was registered within the time periods set out in the Act which usually is 45 days from the date of last supply. Hence if a trade supplied either materials or labour to an  improvement and more than 45 days has elapsed, their lien has expired.