I commisioned another house. I have been building houses for the last 5 years. During these years I have seen that the bricklayers tend to take around 20% less

I commisioned another house. I have been building houses for the last 5 years. During these years I have seen that the bricklayers tend to take around 20% less time than the painters, furniture-installers and decorators. Somehow, in this project, with bricks provided by BigCorp the bricklayers are significantly late, and are delaying the whole project. It doesn't clearly mean anything other than I'm not willing to risk another late house by using again the bricks from BigCorp