[Alfredo]

Greetings:

We need to attach custom wrought iron stair rails to a home with vinyl siding. We've read the post about attaching light items but need some advice about heavy items. The stair rail base(s) will be bolted to concrete at the bottom of the stairs and bolted to brick at the top ofthe steps. This question is about how to attach the top of the hand rail to the home. The area we need to attach to is very narrow, between a window and a door frame. The owner indicated there is solid wood (perhaps a stud) behind the vinyl we need to attach to. We've read the information about being sure the vinyl can float. Best methods / ideas will be appreciated!

 

[buletbob]

I'm assuming the mounting plate is welded to the rail ? not adjustable right. and when they fabricated the rail did the plan on bolting it to the house sheathing or on top of the siding. what I'm getting at is there will be a difference of anywhere 3/4"-1-1/4" if there is backer board behind the siding. You do not want to mack the balusters out of plumb when bolting to the house.
If they planed on bolting it to the house,make a profile of the top rail only , not the plate and draw it on the siding where its going to be bolted . take a roto-zip or snips and cut out the out line 1/4" larger then the rail.
then cut from the bottom part of top rail to the bottom of that coarse of siding in the center. unlock that coarse from the one below and cut out the backer behind it to the size of the mounting plate.install some type of gasket (ice shield ) anything to seal around the mounting plate. and bolt the rail to the stud with the proper lag screw At least 2" long.
Bend siding around rail and over plate and relock to bottom coarse.
If the rail was intended to bolt to the face of the siding, Then you would drill A hole 1/4" bigger then the lag screw your going to use.Then I would get a 3" lag screw and bolt it to the house that way, not snuging it up tight to the siding as to compress it. caulk top and sides only. Hint use a lag that will fit tight in the pre drilled hole on the plate. this way there is less movement in the rail.
Good luck !BOB