Wednesday, December 5, 2007

Concept Model of Demolition Energy for Existing Buildings

We have our embodied energy model down pat. But when we're looking at teardowns, that's only half the equation. The ACHP report also provides a concept model for demolition energy, or "the amount of energy needed to raze, load, and haul away construction materials."*

The concept model provides a second table for demolition energy. The math is simple. Demolition Energy = Gross s.f. multiplied by the demolition energy of materials per s.f. of construction for buildings of similar size and construction type in table 2.

TABLE 2 Demolition Energy of Construction Materials for Existing Buildings

Small Building Size (5000-15000 s.f.)
Construction Type:
Light (e.g. wood frame)............3100 BTU/s.f.
Medium (e.g. steel frame)..........9300
Heavy (e.g. masonry, concrete)...15,500

Medium Building Size (50,000-150,000 s.f.)
Construction Type:
Light (e.g. wood frame)............2400 BTU/s.f.
Medium (e.g. steel frame)..........7200
Heavy (e.g. masonry, concrete)...12,000


Large Building Size (500,000-1,500,000 s.f.)
Construction Type:
Light (e.g. wood frame)............2100 BTU/s.f.
Medium (e.g. steel frame)..........3600
Heavy (e.g. masonry, concrete)...10,500


Now, many (most) homes don't even register on the "small" scale above. But seeing as how demo energy decreases as a building size increases, we think we're being conservative by using numbers meant for 5000-15,000 s.f. buildings to calculate the demo energy of an typical single family home. In other words, the actual energy expended is probably higher.

So, back to our "model" home: 3000 s.f. frame house X 3100 BTU = 9,300,000 BTU. If the same home was made of brick, we're looking at 46,500,000 BTU. Add that to the existing embodied energy, and you're on your way to making a solid case for preserving homes from an energy conservation perspective.


* You are a NTHP Forum member, right? You should be. The journal is great and members can pick up the ACHP report on embodied energy in the pdf file cabinet. Go now!

7 comments:

Unknown said...

There's no doubt that steel plays a vital role in the world economy. But, steel's creation is running straight into the green movement. Governments are increasingly enacting laws which restrict emissions generated by steel production.
Steel recycling programs help alleviate environmental stress by reducing the emissions produced from steel smelting. As technology advances, manufacturers are finding better and cleaners processes for manufacturing steel.
Steel has become the commodity which is building the world. From ancient times until now, people have understood steel's significance for a modern, functioning world.

"Craft Projects International"

Bygningsentreprise said...

Really cool article.

Étienne said...

Improvements to buildings bring nearly immediate and focused benefits to owners, while decisions about density and location have benefits which are more widely distributed and whose paybacks accumulate over a longer period. Housing type is also a very significant determinant of energy consumption. Fairly substantial differences are seen in detached versus attached homes, but the most striking difference is the variation in energy use between single-family detached homes and multifamily homes, due to the inherent efficiencies from more compact size and shared walls among units.
Adirondack Rentals

bondage videos said...

Good to know someone I could share my ideas. Looking forward to know and learn some more from you. I'll be glad to share my own thoughts to you soon.

ker sangri said...

]we prefer to honor many other online internet sites on the internet, even if they aren’t linked to us, by linking to them. Under are some webpages really worth checking out

Anonymous said...

cottage rentals quebec
I have bookmarked your website so that I can come back & read more in the future as well. Please do keep up the quality writing.

Unknown said...

Demolishing the old building, cleaning up the debris and preparing ground for the new building seems like a nightmare. It is definitely not a DIY task as there are so many technical details to look into.

demolition sunshine coast