
Showroom beds often look lower than reality. You stand in the showroom and nod, then buy. That frame sits 15cm higher when you bring it home, which feels wrong. The showroom floor is flat, but your HDB floor might have skirting that eats another centimetre of clearance from the total height, so you need to measure the height accurately before you buy. Most people forget to measure the total height including the mattress. You need to account for the mattress thickness plus the frame legs before you order anything online. This one too high.
Lift doors are the real limit. HDB lift door opening is 90cm wide x 209cm tall, which is the real limit for delivery. If the total height exceeds the door, you kena stuck outside the door, which is a hassle. This one is tricky. Standard Queen mattress is 30cm thick, so add that to the frame legs. A tall frame might push the total over 209cm if you are unlucky. The delivery team cannot lift a heavy frame over the door if it is too tall for the shaft, so measure twice before you order anything online and save trouble. You should ask the ID to measure the room clearance first. If you already bought the wrong size, then you must change. Don't ignore the height. Measure the room again, lah.
Sitting height matters, because 45cm is the sweet spot for getting in and out. Too high means knees hurt, and too low means back pain for your parents. You need to sit down to test it before you commit. Queen size fits most HDB master bedrooms. King in a room under 3x2.5m feels cramped. Leave 60cm clearance on the exit side, and 30cm on the other sides. A flexible mattress can bend into a lift a rigid frame can't, which is why you measure the door before delivery to avoid trouble and save money for the family. Solid-wood and plywood frames outlast particleboard/MDF, so choose wisely.