Building density in plots

SimonBa

Hi there,
sorry but I am quite new to ArcGis and also to this forum so maybe i posted in the wrong category?? and also my English is not the best...

so here is my problem:
I have a shapefile with several plot areas and another shapefile with buldings. So what I want is, in the end, show how much area is covered with buldings for each plot. What I did so far:

Open toolbox
- go to analysis tools - overlay - spatial join
- select buildings2003 as target features
- select plot2003 as join features
- select name and location for output shapefile
- select join_one_to_one and OK
- Open attribute table of output
(I THINK HERE THE MISTAKE ALREADY HAPPENED!)
- right-click on header of plot-id or plot-number (depending on which is
available) and select "summarize
- in the second field select "sum" for the area of the buildings and
"average" for the area of the plots
- Right-click on the output table and select open. This table should
show the plot number, the sum of the areas of houses (in case there are
more than one house in a plot) and the areas of the plots

the problem is, that this operation does not take all the building area in one plot if there is one building in two plots...its difficult for me to descripe so i made a screenshot of my problem...
maybe someone can help me?!!
thank you a lot

Problem.jpg

TraceyBushman

Hi Simuba,

You could try using the 'erase' tool to cut holes out of the plot layer where the buildings layer is.
Then join the 'plot before' and 'plot after' tables
add a new field and calculate the difference between the two layers

regards
Mark

I had a similar predicament and I tried this solution.
Outcome:
Still messing with stuff but this seems to work. Thank you.