Does anyone have any ideas on how to find out the height of a building?I can not use a ladder nor use any siding to make a judgement call on it.There is a peak at the top with a foyer and I don’t have access to the inside
Take a pic of the front streight on. If it’s a modern (post 1930’s) house, the front door is 3’ wide by 6’ 8" tall. You can use this to scale-out the rest of the pic. You can also measure the width of the house & use this for scaling. Most residential structures can be measured for height @ 10’ per floor. Basement windows, if visable and “modern” era, are 32" wide. 40+ years as a carpenter sometimes helps as a MRR’r!! [:)]
Great idea,thanks that will really help.
Lou said it well. Also an industrial building would have cielings in the 10 to 14 foot range. If it is 3 stories it will be 30 to 40 feet tall for example. A peak is usually as tall as a normal floor, the roof slants from the ridge pole to the eaves.
Chris
Starting after WWII, residential building heights are pretty much standardized at nine feet/floor, based on an eight foot ceiling height.
The best way to determine the actual dimensions of a peaked or pitched roof is to get an exact profile, then measure it from the dimensions you have already established. The height of the peak can vary wildly, depending on roof pitch and width. The last house I owned had a very steep roof (steep enough to allow a full height finished attic,) while my present home has a much flatter roof. Even though the eaves width is a lot wider, the ceiling-to-sheathing height is too little to stand up in.
For my own modeling, I have to use a totally different set of standards. The Japanese standard building module is the size of a standard tatami mat, approximately 3 x 6.
Chuck (modeling Central Japan in September, 1964)
Wait for a sunny day, and measure the length of the shadow of the building on the ground. Then, take a 1 foot ruler and measure the length of its shadow. Do this right after you measure the building’s shadow. The ratio of the shadow’s length to the building’s height will be the same as the ratio of the ruler’s length to the ruler’s height.
(Building Shadow) / (Building Height) = (Ruler Shadow) / (Ruler Height)
True story: A class of freshmen at MIT were given this assignment. “How would you use a barometer to determine the height of the Earth Sciences building?” The answer they were looking for was “Measure the air pressure at the top and bottom of the building, and then solve for the height of the building based on that.” But the question was actually meant to get people to “think outside the box” and produce more original thinking.
“Take the barometer to the top of the building and drop it off. Measure how long it takes to fall and smash on the pavement below. Knowing the acceleration of gravity and the time of the fall, solve for the height.”
“Tie a string to the barometer. Lower it from the top of the building until it is just above the pavement. Swing the barometer like a pendulum, and measure the period of the pendulum. Solve for the length of the string.”
“Take the barometer to the basement of the building, and locate the custodian. Tell him you’ll give him the barometer if he tells you how tall the building is.”
Many years ago I wanted to build the station “Naumburg”. I took lots of pictures. Here you see my son Eric as “civil engineer”. In his hand a wooden stick, exact 1cm in H0. [:)]
Wolfgang
Still another method is using trig. I had a tree that I needed the height of. I hustled up a protractor, string, a weight, and assembled them so I could sight along the protractor and pick off the angle. I did this for the top of the tree and the base of the tree. I knew the distance to the tree. Plug in the numbers.
For a building on an approximately flat surface, if you can sight a 45 degree line to the top, the height will be the same as your distance from the building plus your height.
Love the barometer solution(s), Ed
PS: On a physics test for extra credit: “What’s the speed of light in furlongs per fortnight?”
Quick! How many seconds in a nano-century?
The answer, to a surprising degree of accuracy, is pi.
What you describe is not really trig. It’s just plane geometry. Two angles and the included side, or two sides and the included angle determine a triangle. Use a carpenter’s level to be sure the ruler is perfectly vertical.
Mr. Beasley got it right.
Fun [:D], but not statistically significant [:(]. Off by over a full percent. Just one of those really cool numbers “facts” that astound the masses. I love math!
OK - Stick method and trig method are great. Photo method only works if you are straight ahead of the center (vertical) of the object. If you have photoshop you can cheat with the “perspective cropping” method. It will be close enough.
Karl
height of tree = tangent of angle x distance to tree
example:
distance to tree is 200 feet, top of tree is 30 degrees up from level
height of tree = tangent of 30 degrees x 200 feet
height of tree = .577 x 200 feet
height of tree = 115 feet
That is what’s called trigonometry.
What complicated it a bit for me was that the ground dropped off towards the tree so that I had to both work up and down to get a decent number.
Ed
I guess my plane geometry teacher didn’t know he was teaching us trig when we went out in the front yard and calculated the height of the school building.
I guess we were really advanced.
If your plane geometry teacher taught you the use of trigonometry tables, then both he and you were certainly advanced. There’s nothing wrong with “learning ahead”. In 4th grade, I had a teacher that was so comfortable in math that she taught us 5th and 6th grade math too. She made it look easy. Great teacher!
Ed