In both real-estate and construction, using square footage as a cost-based metric is common practice.
Here is the
- Real-estate goes by “conditioned” square footage
- Builders go by “framed” square footage
Why you ask? Great question! My hunch is, the real-estate world uses “conditioned” square feet for simplicity sake. While searching for comparable properties, used to justify price point, conditioned square footage is the most generic and standardized way of quantifying how much a space is worth. Basically, a house in the same neighborhood, built around the same time, kept up in similar fashion, should be worth a similar price per square foot of air-conditioned (aka: “livable”) space. And, the non-conditioned (aka: “non-livable”) spaces should be looked at as nice (but non-quantified) extras, like the icing on top of the cake!
Wait not so fast…
Builders like myself typically reference price per “framed” square foot. Why not use “conditioned” square feet like the realtors? Easy answer, we have to pay for all of the square footage we build, conditioned or not. The decks, covered patios, staircases, garages, even swimming pools; all use very similar resources to their conditioned counterparts.
Why does this matter?
Logistics and expectations is the answer. If you are designing a new custom home, and your build partner tells you they can build a high-performance home with medium end finish-out for around $250 per square foot, they are talking “framed” square foot, NOT just “conditioned.”
Well, you may be thinking: Non-conditioned square feet should cost less to build, so why would they be priced the same as conditioned square feet? Remember “price per square foot” is just an average. Kitchens and bathrooms typically cost more than bedrooms and living rooms, conversely (and depending on what you’re building) sometimes exterior spaces cost more per square foot than interior spaces.
Until an actual line-item estimate is completed, these square footage numbers are just a dialog starter, typically used to guide the financial limitations of a custom home’s design.
Summary: Pricing by conditioned square feet may work for real-estate, but when talking construction always account for what you are actually constructing (not just conditioning), otherwise you literally may be left out in the cold!
Doug Cameron is a Healthy, High-Performance Builder & Remodeler with EcoSafe Spaces Design+Build in Austin, TX