Useful Stuff 5: The National Building Code

Have you heard the phrase, "Authority having jurisdiction"? This refers to the municipality or regional district building inspectors who interpret each country's National Building Code.

When you take out a permit for your dream house or renovation project, it is prudent to check with the local authority having jurisdiction. These people are approachable. Organize your questions first and then phone them in the morning before they go out on their rounds. Some of the questions you could ask and should ask are the following:

  • What depth do I have to go with the bottom of my footings? This varies from 2' to 8' depending on where you live—near the coast or in the interior. The deeper the frost penetration in the wintertime, the deeper your footings have to go for protection.
  • On the other end of the scale—what is the snowload on my roof in my area? This question wouldn't apply to a new home builder who purchases trusses, since they are engineered for local conditions. Snowloads are important when you're putting on a shed roof or even a gable roof over an added on bedroom when the size of the roof joist or rafter must be determined. Look in the Code. Snowloads vary from 1.0 kPa to 2.5 kPa, where one kilopascal equals 20.88 pounds per square foot. Yes Canada's NBC is in metric. Some jurisdictions require footings and walls to be poured separately. Others don't care. Some require an inspection visit before each pour. Others don't want to come out to inspect again once the footings are poured. Their next call would be the framing inspection.
  • Before you put the windows and exterior doors in, check with your building inspector to see if he wants tar paper around the openings. Some inspectors prefer none at all.
  • Perimeter drainage is also an ambiguous exercise. Is big-O allowed? Are rain water leaders tied into the storm sewer or expected to run onto the ground to disperse the water on it's own?
The planning stage of your project is the best time to sort out these kinds of questions and overcome any problems. Then your project will move smoothly along. Why waste your sub-contractor's time and your money on doing jobs twice when the first time could have been done correctly according to the Code. Remember, don't argue with the inspector. After all, he is the authority having jurisdiction.


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