Cost per square foot vs cost per unit: which should builders use?

Builders should use both cost per square foot and cost per unit, but for different questions. Cost per square foot helps compare construction efficiency when square footage is defined consistently. Cost per unit helps compare multi-unit projects where shared site, utility, design, and sales costs affect each unit differently.

A multi-unit project can look efficient per square foot and still be weak per unit if shared costs are high.

A small project can look expensive per square foot because fixed costs have fewer square feet to spread across.

A four-unit townhome project with $2,000,000 in total cost equals $500,000 per unit. If it has 6,400 finished square feet, it equals $312.50 per finished square foot.

Both numbers are true, but they answer different questions.

Illustrative numbers only. Not Bivvit benchmark data.

• Finished square footage definition.
• Unit count and unit size mix.
• Whether land, soft costs, and financing are included.
• Allocation of shared site and utility costs.

Bivvit keeps the denominator visible so cost per square foot and cost per unit are not mixed casually.

The report states which costs are included before comparing projects.

• Cost per square foot guide
• Project normalization
• Compare completed projects