i got a small area about 60 square feet of unventilated attic space. i think one of those square side wall vents should do the trick to ventilate. i don't want to cut into the roof and do it that way.

so cut through siding and plywood with a circular saw in between studs, put in vent, screw in, caulk the seems, done. right?

is it that simple? anything i'm missing?

That's about it, although a second vent on the other side seems like a good idea to provide cross ventilation.

Sawsall !!!:hihi:

sounds good. Layout the vent on the siding so you can shove the top flange of the vent up underneath the siding for better water shedding. If you have cedar shingles take them off around it and redo up against vent to look neat. Siding a little more diffucult. If you have soffit vent or ridge vent than another vent is probably not necessary. If not 2 would be better.

all the newer homes had ridge vents installed

i guess yours didn't then...

an older building perhaps...

That's about it, although a second vent on the other side seems like a good idea to provide cross ventilation.Good idea, If your has house central air or room a\c units and your house is closed up (windows,doors)without a second ventilation
source the attic fan will cause a down draft in the chimney and cause
havoc on your boiler or water heater. Possibly carbon monoxide poisioning in exterme cases.