Movie Building Inspector #1

It's time for episode 1 of Movie Building Inspector, where today we are responding to reports of violations at a certain school for wizards and witches... I hear it's one of those liberal ones over in Europe.  Let's just take a look in the main hall and GAAAH!

Hogwart's Dining Room

Holy crap, Hogwart's is a fire hazard if I have ever seen one!

Sure, heavy timber construction is better than light frame, but lets back those 5,000 open flames away from the roof structure, unless you have an anti-litigation spell for all those angry parents of flattened children - class action suiticus dismissum! The more resistant the structure is to heat, the bigger the building can be! Also, should Hogwarts have a proper sprinkler system (which they do, although the fairies-with-tiny-buckets-of-water system is only approved for use in England), the structure could be enlarged and travel distances to exits lengthened. See the chart below for Construction Types.

Click to enlarge

Who isn't a fan of magic stairs that swing from corridor to corridor? Of course, this design would get an immediate stamp of rejection from the DOB...

Stairs to Gryffindor Hall

If you want to bring these up to code, here's a few design rules you should know:

• Handrails at the bottom of stairs shall extend 12" plus extend the slope for a horizontal distance the depth of one more tread. 
• Vertical distance between landings may not exceed 12'-0" with headroom clearance no less than 6'-8".
• Monumental Stairs are stairs 88" in width or wider and require intermediate handrail.
• Avoid single steps; where there are more than three steps, handrails must be provided.
• Handrails must be located 34"-38" above nose of stair or ramp.
• Width of an egress stair is based on occupancy: in most cases, 44" is the minimum but you can go to 36" in a residential occupancy.
• American Disabilities Act requires the below dimensions for handrail design:

You should always refer to your local building code for regulations regarding stair design, as they may have added a few requirements of their own.

NYC Hurricane Irene Special! - Intro to Wind Forces

Bad weekend to start your construction project in the Tri-State area.  Or end your project.  Or be a contractor on a project:  just look at all of their responsibilities to comply with the NYC's Deparment of Buildings:  


To secure construction sites, builders, contractors and developers should take all precautionary measures including but not limited to the following: 

• Tie down and secure material and loose debris at construction sites.
• Cover electrical equipment from exposure to the weather.
• Store loose tools, oil cans and extra fuses in a tool box.
• Secure netting, scaffolding and sidewalk sheds.
• Suspend crane operations and secure crane equipment when wind speeds reach 30 mph or greater.
• Suspend hoist operations and secure exterior hoists when wind speeds reach 35 mph or greater, unless manufacturer specifications state otherwise.
• Brace and secure construction fences.
• Secure all windows.

Owners don't have it any easier:

• Bring inside loose, lightweight objects such as lawn furniture, potted plants, garbage cans, garden tools and toys.
• Anchor objects that would be unsafe outside, such as gas grills or propane tanks.
• Close up and secure patio umbrellas.
• Secure retractable awnings.
• Clear rooftop drains, gutters and leaders.
• Secure all windows.
• Remove aerial antennas and satellite television dishes.

Architects' responsibilities include:

• Do not go in to work.  Drink if necessary to prevent this.
• Continue to peruse job postings on Craig's List.

Now, on to wind:

EFFECTS OF WIND ON BUILDINGS

• direct pressure
• drag
• suction
• rocking, buffeting
• vibration
• clean-off effect:  wind gusts have more effect of building parts than the whole building

CRITICAL WIND EFFECTS

Codes provide critical wind velocity and design wind pressures.  Wind speeds are taken from the code, and are based on historical data measured at a standard height of 33' above the ground.  Factors considered by code are building size, building shape, openness and sheltering effect of surrounding landscape, and various special conditions.

Wind forces determined are:  

-  inward pressure and outward pressure (suction) on exterior walls

-  pressure on roof

-  overall force on the building

-  sliding and overturning forces - resisted by dead weight of building)

-  harmonic effects - resisted by stiffening/bracing/tightening of elements)

-  effects of openings - forces are increased at openings, these can be calculated via a wind tunnel test
torsional effects - twisting of elements about the centroid, or center of stiffness