Layout Efficiency Ratio

Efficiency ratio is calculated by dividing a unit's internal usable floor area by its total quoted strata area, expressed as a percentage. It varies by development, by unit type, and even between stacks within the same project, driven by how much bay window, ledge, planter box and structural column space a particular layout carries.

This matters to a buyer because two units priced at the same PSF and the same quoted area can offer noticeably different amounts of real living space if their efficiency ratios differ. That difference affects both how comfortably a unit lives day to day and how it may be perceived when it comes to resale, since buyers viewing a unit will judge the space they can actually use, not the number on paper.

Efficiency ratio is rarely printed on marketing materials or a balance units chart, which commonly misleads buyers who compare projects purely on PSF into thinking they are comparing like for like when one project's units are structurally less efficient than another's. A compact looking floor plan is not automatically inefficient, and a large quoted area is not automatically efficient, so the ratio needs to be worked out rather than assumed from a glance at the plan.

Ask for or calculate the internal floor area against the quoted strata area for each unit type you are seriously considering, ask specifically how bay windows, air conditioner ledges and any void or planter areas are treated in that calculation for the particular project, and weigh the ratio alongside layout, facing and stack rather than treating it as the sole basis for a decision.

Winfred Quek is an Associate Marketing Consultant at Crestbrick Pte Ltd (CEA Licence No. L31010886H). CEA R073319H. This page is for general information only and does not constitute financial, investment, or legal advice. Verify current figures with IRAS, HDB, CPF Board, or MAS before making any decision.