Help! Can I notch this stair stringer and replace with Skirting?

[Hibleton88]

Hi, I’ve been a long time follower of the forum but have been moved to post for the first time after encountering some frustrating issues with the staircase in our new house.

The house was built circa 1905 and wall on the left hand side of the stair was either built wonky or has moved in the past. As a result, it gives the appearance that the stringer at the bottom of the stair is approximately double the width that it is on the top of the stair.

we wanted to put decorative skirting at the bottom of the stair that would continue up the stair skirting and continue again at the top of the hallway, but the difference in widths is making this pretty difficult.

We thought we could notch the stringer and just lay the skirting over the top, however, on investigation it looks like the stair is a solid stringer (if that’s the correct terminology?) so the treads are routed into the stringer and the stringers are just one solid piece.

does anyone have any ideas about how you could achieve the continuous skirting look we were hoping to achieve? Or has anyone experienced the same problem?

many thanks.

 

[Deleted member 174758]

You need to get a full length piece is 1in nominal (22mm thick finished) softwood tonnage up a scribed strip. This will probably need to be 10in (250mm) wide or wider. You then need to mark the profile of each of the steps (tread, riser and nosing) on the scribing strip and carefully cut them out with a small circular saw and a jigsaw, remembering to makr your cuts in such a way that you get a 5° to 10° undercut, not a 90° square cut - this is essential for finsl fitting. Clean-up and finsl fitting can be done with a block plane, wood files, rasps and rat-tailed files. You are aiming for a gap of 1mm or less at any point on the scribed edge. A profiled edge is either worked with a router after the scribe has been completed, or a moulding is planted on and pinned in place after the false stringer has been fitted

This is not an easy job to do, requiring skill, judgement and patience. Even an experienced tradesman may need two stabs at a task such as this to get it just so. To stand a chance of doing it to an acceptable standard it is easiest to make up a template from something like 6mm MDF and get that scribed to fit correctly before transferring the profile to solid wood and then cutting and scribing that. This is because on an old staircase I'd expect every step to be slightly different, so there's no making up a single step template and using that multiple times to make the full size template. I'd expect even a good chippie to take well over a day on an old staircase like yours to do this for each side.

On a technical point: if the house was built in 1905 it pre-dates power routers (the world's first was probably the Kelly router of 1907, but they are rare in the USA, where they come from and I very much doubt that any ever got here. Your stringers were possibly made on a recessor or a spindle moulder (both of which had accessories for stair trenching before 1900), or possibly a purpose-made stair housing trencher - but you might find if you look underneath that it was hand made using just saws and chisels. They were still teaching us to do that at college in the 1970s

 

[Hibleton88]

Thanks Jobandknock,

My concern with taking cutting the stringer out would be whether it would affect the structure of the stair. Do you think it would cause an issue? I tried to look at it from underneath from our neighbours flat but it’s all boarded in.

 

[Deleted member 174758]

My concern with taking cutting the stringer out would be whether it would affect the structure of the stair. Do you think it would cause an issue?

Yes. Your stairs could collapse. You never, ever cut into a stringer in that way. They are structural. It could be very dangerous.

Please take that advice as being from an experienced carpenter and joiner.