Winder into existing staircase

11 Dec 2018
Reaction score
United Kingdom
Good evening,

I'm looking to get started on this project over winter, just hoping for some guidance before i dive in.

The staircase as it currently stands has two straight flights, with a half-landing about 1/3 of the way up. I am looking to change the top 3 steps for a winder, allowing me to move one wall giving me a third bedroom, and also a second bathroom.

I've found a product 'kwikstairs', it seems like it would be the easiest way to go about this.

My rough plan for this is to support the string which is not against the wall (couple of 2x4s down to ground floor/up to first floor landing?) remove treads and risers on the top 3 steps, cut the wall side stringer at same point.

Then mount new winder box, notch newel to sit over landing floorboards, screw through to landing where existing stairs end, and screw onto the wall flush to the cut stringer. The 'floating' stringer id also screw to new newel post.

Does this sound reasonable?

The stairs are 900mm wide, with the treads being 250mm deep. Id be looking to have the winder box 900x750. Is it okay/advisable to have the top step narrower?

Hopefully with the pictures this is alot clearer than I'm describing it!


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