Our clients brought this up from their house in Washington DC, but you could probably look at restoration hardware for something similar.

What are the widths of the baseboards & casings?
I have a '50's house and I'm thinking of using 5 1/2" base with 3 1/2" casings but I'm not sure if the oversized trim (and 2" difference in trim) will look good on small doors and narrowhallways. Perhaps a 5 1/2" base, 3 1/2" leg casing and 4 1/2" head casing would look good?

The side casing is 4 1/2" and the head casing is 5 1/2" and the baseboard height is 7 1/4" high - proportions which we have come to love.

Love the trimwork and all of your work actually! I find myself referring back to your projects multiple times for examples of what I am looking for! Thanks! Could you tell me what type of wood you use for the trim and casing on your homes?

Typically poplar is used for painted trim around here. Our builders often biscuit joint, glue and screw to keep the trim from separating as it moves over the seasons with changes in temperature and humidity.

Thanks for your prompt response. Even the normal trim separation is better than the MDF option though isn't it? Gives the house character! Glad to hear there are ways to minimize that.