First - is the rough openning framed?

Is it the right size?

Is it a plumb wall?

or are you replacinga door already in the wall, and if so, is it with sidelites also?

Best answer based on what I know from you so far is to buy the unit as a prehung door with sidelite and just install according the the instructions that come with it.

Excellence is its own reward!

yes the rough opening in place it is plumb and it is the first door to be installed in the opening, i bought the door at an auction and have never installed a door with sidelights, also not sure of the manufactuer its a mahgony door. thanks for your help

so is it a prehung withthe sidelites a part of the unit or are you attempting assembly and building jamb?

Excellence is its own reward!

it is all one unit sidelights attached, just not sure how to properly attach it to the rough opening on the inside of the door unit there is no recess or area to screw the door unit to the rough opening only on the outside is it ok to fasten the door on the outside? sorry dont' mean to make this more complicated than it has to be.

thanks for you help

There should be ext casing such as flat stock or brickmold.

You check that the floor is perfectrly level, then set a floor pan or Vycor to keep water out. Then lay a bead or two of good caulk like a silicone or Geocel and place the door unit in place on that.

Make sure it is al level in every way, and nail the casing to the framing.

Add shims at sides, and use casing nails ( for me this is 12d galv finish nails or 3" trimhead screws ) from jamb, through shims into frame. Goo up into header also, but with no shims there. If header deflects, you do not want to settle on the door

Then use low expansion spray faom in modest amts to fill the gap which also glues the unit into the frame.

Excellence is its own reward!