A 52-year-old man presents to his family physician after an elevated blood pressure was noted at a work health fair. He is asymptomatic, with BMI 29 kg/m2 and a 15 pack-year smoking history. Automated office blood pressure measurements taken correctly after 5 minutes of rest average 148/92 mm Hg at today's visit and 146/90 mm Hg one week later. Baseline blood work and urinalysis are normal and there is no end-organ damage on examination. According to Canadian hypertension guidance, what is the most appropriate next step to confirm the diagnosis of hypertension?