I Can Build, I Can Build!
Whoa there Nellie…..before getting all carried away, there are 14 essential questions to have on your Building Department Checklist, in order to ensure the structural part of the new building process goes off without a hitch. I will cover the first seven today, finishing up tomorrow, so you have a chance to take notes, start your own home file folder of “what to do before I build”. Careful preparation is key to having a successful pole building outcome.
#1 What are the required setbacks from streets, property lines, existing structures, septic systems, etc.?
Seemingly every jurisdiction has its own set of rules when it comes to setbacks. Want to build closer to a property line or existing structure than the distance given? Ask about firewalls. If you construct a firewall, you can often build closer to a property line. Creating an unusable space between your new building and a property line is not very practical. Being able to minimize this space could easily offset the small cost of a firewall. As far as my experience, you cannot dump weather (rain or snow) off a roof onto any neighbor’s lot, or into an alleyway – so keep those factors in mind.
#2 What Building Code will be applicable to this building?
The Code is the Code, right? Except when it has a “residential” and also has a “building” version of the code, which do not entirely agree with each other. Also, every three years the Building Code gets a rewrite. One might not think there should be many changes. Surprise! As new research is done, even things which seem as simple as how snow loads are applied to roofs..changes. It is important to know not only which Code, but which version of the Code is being used.
#3 If the building will be in a location which receives snow, what is the GROUND snow load (abbreviated as Pg)?
Make sure you are clear in asking this question specific to “ground”. When you get to #4, you will see why. Too many times we’ve had clients who asked their building official what the “snow load” is, and the B.O. replied using whichever value they are used to quoting. Lost in the communication was being specific about “ground” or “roof” snow load.
As well, what is the snow exposure factor (Ce) where the building will be located? Put simply, will the roof be fully exposed to the wind from all directions, partially exposed to the wind, or sheltered by being located tight in among conifer trees which qualify as obstructions? This is a good time to stand on the building site and take pictures in all 4 directions, and then getting your BO to give their determination of the snow exposure factor.
#4 What is the Flat Roof Snow Load (Pf)?
Since 2000, the Building Codes themselves are written so as the flat roof snow load is to be calculated from the ground snow load. There is actually quite a science involved in this, and it takes into account a myriad of variables to arrive at a specific load for any given set of circumstances.
Unfortunately, some Building Departments have yet to come to grips with this, so they mandate the use of a specified flat roof snow load, ignoring the laws of physics.
Make certain to clearly understand the information provided by the Building Department in regards to snow loads. Failure to do so could result in an expensive lesson.
#5 What is the “three second gust” wind speed in miles per hour?
The lowest possible wind speed (85 miles per hour) is only applicable in three possible states – California, Oregon and Washington. Everywhere else has a minimum of 90 mph. The highest required in the United States is 146. Don’t assume if a friend of yours who lives in the same city has the same wind speed. The City of Tacoma, WA has six different wind speeds within the city limits!
#6 What is the wind exposure (B, C or D)?
Take a few minutes to understand the differences. A Building Department can add hundreds, or even thousands, of dollars to the cost of a project, by trying to mandate an excessive wind exposure. Again – this is a good place to take photographs in all 4 directions from your building site. Some jurisdictions “assume” the worst case. Meaning, your property could very well be protected on all 4 sides and easily “fit” the category B wind exposure requirements. However, your jurisdiction may have their own requirement everyone in their area is wind exposure C, no matter what. It’s their call.
#7 Are “wind rated” overhead doors required?
Usually this requirement is found in hurricane regions. My personal opinion – if buying an overhead door, invest the few extra dollars to get one which is rated for the design wind speed where the building is to be constructed. This is a “better safe, than sorry” type situation.
I’ve covered 7 of the most important questions for your Building Department Checklist, and they really weren’t so difficult, were they? Come back tomorrow to find out the last 7!