Batt Insulation - Not all are poor!

Gregory La Vardera posted this excellent primer over at Green Building Adviser on the differences between fibreglass and mineral wool batts.

As Gregory points out, ROXUL Mineral Wool batts are not associated with the typical failings of a fibreglass batt installation. This is due to the density of the product and the ease of cutting and trimming. The product also sheds water and is fireproof.

My only critique of his article is is statement "I don't need my insulation to make an air seal, because I used that good ol' housewrap on the outside. Nope, nothing wrong with housewrap — but it provides no help with the air sealing you need at your vapor retarder. The air seal in this case wants to be on the warm side of the wall, to prevent interior moisture from entering the wall cavity and condensing during the winter heating season."

This is actually incorrect, an air barrier ANYWHERE in the assembly will block air flow through the assembly.  I will talk more about this in an upcoming blog entry.  For now, I did not want to detract away from the rest of the posters review of ROXUL mineral wool insulation.

Blog vs Journal

I just want to give a heads up to regular readers of this blog that I will be reserving future posting for the more in-depth postings regarding materials, processes, and Building Science.

I will be making the more regular (hopefully daily once I start building) postings, describing my day to day struggles of building my own house, to the project journal at theEnclosure.ca

You can subscribe to this journal page if you want to automatically receive the updates.

I want to thank you for the amazing support you have all shown by being regular visitors of this blog.  When I first started it, I would have never imagined I would receive over 1000 visits a month.

ENGINEERING GUIDE FOR WOOD FRAME CONSTRUCTION 2009

Looking to borrow a copy of the Canadian Wood Council's ENGINEERING GUIDE FOR WOOD FRAME CONSTRUCTION 2009 from someone in the Lower Mainland Greater Vancouver Area. 

Hopefully Saturday AM.  I have ordered a copy but it will be a week or so coming and I would like to get a handle on Part C over the weekend if possible. 

If you have a copy I can borrow, please contact me at building@senwi.ca

Many Thanks

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.

The End?

This has been a particularly poor day.

You can read about it on the build websites journal http://www.theenclosure.ca/?p=541

In a nutshell, it appears my dream to build a Part 9 affordable structure is coming to a close without too many options I can afford.

Really not sure what my next steps will be and ironically, my services were disconnected this morning and I do not even have the opportunity to move back in.

Time to go for a walk - Sorry for the downer but thanks for letting me vent!