HK21 Building Services is a plumbing business at 140 Upper Bukit Timah Road in Bukit Timah, on the main road that runs north from Beauty World toward the Dairy Farm area. Plumbing work in the area is shared between a few firms: Plumbing Hub Express is on the same spot with 4.8 from 139 reviews, and Greenwood Electrical & Plumbing Services is 0.3 km away with 4.9 from 273 reviews. Customers wanting a plumber nearby will find HK21 among the three options within a kilometre.