Converting a duplex to triplex on R-4?

[John Wanberg]

I am looking at buying a duplex, and potentially converting the basement to a third unit.  What is the process for properly converting a property from a duplex to a triplex, and how difficult is it?  Zoning is R-4 in Aurora. 

Thanks! 

[Bill S.]

@John Wanberg so it's a bit like asking how to convert my El Camino to a 4x4. At any rate here are some thoughts.

1) if the property already has all the features (ie 3 kitchens) needed then probably nothing needs to be done. Without digging into zoning code, I am assuming you have done your homework and the current zoning allows the use so you would be good to go. 

2) If it doesn't have everything needed, then you need building permits to do the work. Doing a project like adding a third unit could mean you would need to bring the whole structure up to current code for the proposed use. They have now added energy requirements to the code (not sure if Aurora follows this but I know Denver does) so if the walls are not adequately insulated you have to insulate them and if the windows are not adequate then you have to replace them. The list goes on and on. 

3) I would recommend you find someone who has walked that path (adding a unit) to a building and see what they say. Probably going to be fairly hard to find. A good architect would be someone who could help. By good I mean, practical, knows the building code, and is not afraid to push back at the City in a gentle but firm manner.

Let us know what you find out.