Wednesday, 9 April 2014

Death of Part 9 construction?

Never would I have guessed that the Building Permit process would be the biggest stumbling block in building your own house.  I know the building code quite well and had ensured my design complied with it.  What I did not allow for, and what may shut me down, is bureaucracy.

It seems that there is a general movement in Municipal building departments across the Lower Mainland to 'opt-out' of Part 9 construction now that this part of the code includes 9.23.13 Bracing to Resist Lateral Loads Due to Wind and Earthquake.  Whether the motivation of the Municipalities is based on fear (many may not be adequately trained on the new requirements that were enacted just last December), or from a perceived workload concern - I am not sure.  It may also be an unjustified fear of liability perceived present if they are responsible for ensuring a dwelling meets the new Part 9 requirements.

Whatever the motivation, the outcome may very well be the death of Part 9 construction in parts of BC and the significant increase in construction costs as a result.  With the added costs of an 'engineered' approach to the Lateral Load design expected to be somewhere in the $20K - $30K range )most of this would be for the added Simpson hardware utilized in most engineered designs), this 'component' has gone from $0 to one of the most expensive components within the home, on par with a high end window, cladding, or HVAC package.

For me, the removal of my ability to generally design and build my own house is similar I am sure to how some Americans would feel if your tried to take away their guns.  I have always felt it is my right to design and build my own house via the prescriptive path of Part 9 in the BC Building Code.

Yesterday, I was informed that this right is being taken from me.  The DNV building department manager has informed me that my architecture is 'complex' and as a result, they will require that the entire structure is engineered including the lateral bracing requirements.

"We consider your proposal combining part 9 prescriptive design with part 4 structural components inadequate in providing lateral support against high wind and seismic forces.

We consider this as a complex design and as such we, the Authority having jurisdiction, decided not to accept the design path and therefore require you to have a Structural Engineer design and provide signed, sealed drawings for the entire structure."

Many of you will be saying, we have combined Part 9 and Part 4 design for decades and you would be right.  In November of 2013 it would be very common to have a primarily Part 9 designed dwelling that also included manufactured components designed to Part 4.  These components would include manufactured floor joists, beams, and roof trusses.  

What changed?  Well the building code introduced lateral bracing requirements in high wind and seismic zones.  This includes the Lower Mainland of BC and the Southern Vancouver Island region.  The requirement became effective in Dec 2013 and right away a controversy developed.  APEGBC in their infinite wisdom decided that the Part 9 lateral bracing prescriptive design was inadequate to resist high wind and seismic loads.  Now of course we have decades of experience showing otherwise, but they have drawn their line in the sand and refuse to budge.

So while engineers are allowed to design to the rest of Part 9, they are specifically not allowed to use 9.23.13  and must instead design the lateral loading using the Canadian Wood Council guidelines or utilizing a 100% engineered approach (Part 4). And the problem with these approaches (granted based on my limited exposure) is that it is a LOT more expensive to build in this manner as it usually includes significant volumes of manufactured Simpson Strong-Tie hardware.  On a house under construction that I often visit, I was quoted a cost of $16K for just the anchor bolts.

Whether this controversy has influenced the building departments, I do not know, but based  on comments made by the DNV manager, many Lower Mainland building departments are getting out of the Part 9 business.  

Personally I question if this is an abuse of the Municipalities power over the code implementation and feel the need for Victoria to step in and mandate Municipal support for Part 9 design and also introduce a detailed frame work that identifies the conditions that must be present in a design before the AHJ can deem that design as 'complex'.  In short, I believe it is time for a major overhaul in how the Building Code is implemented across the Province to ensure a consistent and fair application across AHJ.

In the meantime, I urge you to specifically ask your Municipality what there requirements are going to be while you are still early in the design.  I was notified of my Municipality's unwritten policy after the design was complete during my building permit application meeting.

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