I am having an issue with creating dormers in the Sims 3. I find that my Raise Elevation tool is so sensative that I can't raise it two clicks accurately to set the foundation.

I've been using PlasticBox's dormer tutorial that she created for the Sims 2, and I can get pretty far until it comes time to demolish the sloped side walls. Because there are no half-walls (as of yet), I've been using the porch (?) roof to try and fill in the gaps. However, it's not tall enough and so there are really small open spaces once the roof goes up.

Is there a work around to this problem? Are there any others who have experienced this issue? I know there are some tricks to getting different heights for general roofs, but I haven't been able to get those tricks to work for my dormers.

I was having a tough time using the terrain tools precisely. To get accurate clicks I bound a macro key on my keyboard to left click. I did this through the Logitech mouse/keyboard settings. If it still repeats too fast you can bind double click to a key or mouse button. Double click won't repeat. If you have a Logitech mouse or keyboard and can't bind the key you want, google uberOptions, a (safe) driver extender for Logitech that allows you to rebind almost anything to almost anything. Then in build mode simply use your newly bound button to make accurate adjustments. Btw, if you have problems with a single click bind repeating, assign it to a key that just requires a tap (the zoom in key on my keyboard works for this).

P.S. I also bound my mousewheel's tilt left/right keys to rotate right/left in game (period and comma) and my mouse's volume forward/back keys to floor up/down (page up/down). Very handy.

As for the mouse click sensitivity, one may check out your Os and/or mouse property can enable you to tune your mouse sensitivity.