In the construction field, your only chance of a job is London at the moment. This is where the large construction jobs are at the moment.
As a project coordinator with only one year's experience and no degree, you would not be able to get a work visa. Every UK construction company is laying off staff, and good staff at that, because of the shortage of work. In addition, your UK employer has to be licenced to employ non EEA nationals and advertise the job for four weeks extensively. It could only be offered to you if your employer can prove that not one single suitably qualified EEA national applies. That would be quite impossible for that role at this time. The only exceptions are shortage occupations which are mainly specialist science, medical and engineering occupations.
If you are eligible for an ancestry visa because you have a British born grandparent (or Irish born before 31 March 1922), you can apply for a five year visa without having to meet the work visa criteria and without an employer having to apply the resident market test.
As a Canadian you can always come over for two years on the Youth Mobility Scheme. This is a two year visa which you cannot extend, renew or change into a work visa.
However, your diploma would probably not get you the same level of job in the UK. I'm not trying to do you down in any way, but a non UK qualification that is not a degree will not get you a job over someone with a British qualification when the employer has so many out of work people to choose from. It's an employer's market right now.
If I were you and you are able to take advantage of either of these options and you seriously want to add to your resume by working in the UK, wait until the recession lifts in a year or two and jobs are plentiful again. Construction is boom and bust. There are either too many skilled workers or not enough. Your time will come and a couple more years experience will improve your chances of employment in the UK. Also, try to get a construction related qualification that is recognised in the UK.
You will also need a CSCS card to work for any decent contractor or client. Although you can't take the test in Canada (at least I don't think you can), you can at least study for it so you can take it as soon as you get to the UK