Monday, May 18, 2009

Sustainable Steps for Housing

The housing industry continues to struggle and is perpetually on the forefront of the green movement.  Homes and buildings are the most utilized assets and consume the most resources to both build and operate through their useful life.   While builders can include many sustainable features that reduce future power, water and resource consumption, the responsibility to reduce usage is up to the future owner.  Green features are sellable, but the opportunity to reduce ecological impact begins much earlier in the process. Today the focus needs to be on material usage and waste on the jobsite. 

Several misconception exist surrounding material usage and waste.  One major misconception is that if you see no additional material orders, quantity estimates must be accurate.  The reality is, additional orders is a better indicator of performance than no orders at all.  In the best case scenario, only the amount of material needed in the structure would be ordered originally and any mistakes or extra would result in additional orders.  Great for materials, but bad for transportation.  There must be a better way.

As an estimator, I was taught three methods for estimating a homes materials and labor.  These methods are the Good, Better and Best.  Good methods are just that; they are pretty good but fail to rise to the occasion when it is important.  (Pretty Good, by Charles Osgood)  The good method consists of tested Rules of Thumb; methods that get close enough to the right number to ensure extra material is not needed.  The better method starts with a rule of thumb and applies additional thought to the process.  The best method takes an entirely different approach and, in the end, drastically reduces material and labor needed to build a home.

A great example is estimating the stud count for framing.  While less applicable today with the introduction of wall panels in typical home construction, it provides a spectacular example of Good, Better and Best:

  • The Good – The rule of thumb for studs tells us that a wall with 16” spaced studs, estimating 1 stud per lineal foot of wall is sufficient to cover studs for the wall as well as king, trimmer and cripple studs needed for door and window framing.  Close, but efficient structures, which are typical in production homebuilding, require a lot fewer studs and incorporate varying spacing based on the structural needs of the wall.
  • The Better – The better methods starts at a one stud per foot methodology, then logically backs out studs, based on experience, to produce an end number.  This method is useful for a one-time build, but still leaves a large opportunity for savings, either in less material or saved trips to the jobsite. 
  • The Best – Taking the entire process back to formula, and putting aside estimating, the best method determines the actual stud usage in the wall, then based on industry cull rates, adds material to the estimates to cover the material in the wall, the cull rate and nothing more.  The best method does not add material for mistakes and what-if’s as the method requires accurate plans and homes built to these plans.
  • Verification – The best method, because of the estimating methods, creates verifiable numbers.  These quantities, once constructed, can be verified and corrected.  Once a number is verified, it is no longer an estimate, but actual quantities required for construction.

Material waste represents a significant cost to both the builder and the end consumer.  Material waste also creates unnecessary impact on the environment through use of raw material, processing (heat, beat or treat) and waste sent to a landfill or down-cycled into less useful products.

To learn more about reducing waste in all construction processes, contact me at and request a no sales pitch White Paper from Scott Sedam and True North Development.  To learn more about Best Estimating practices, submit a request to