The best way to deal with this matter is to issue an instruction requiring the defects to be eliminated followed by a compliance notice under JCT Standard Building Contract 2009 clause 3.11 or JCT Intermediate Building Contract 2009 clause 3.9. Should there be no compliance within a week, the employer is legally permitted to engage others and costs incurred by the employer can be subtracted from the contract sum. Should the employer be willing to wait until conclusion of the rectification period, defects can be added to the schedule of defects and addressed in a more routine manner.