How to (and not to) build a spiral staircase...

A woman with a 1890's vintage Victorian house wanted a staircase to connect the first floor of her house to an apartment that had been added in the basement. She was accumulating grandchildren and needed to be able to accomodate more guests. She found a space in the front entry hall where a spiral staircase could fit, giving good privacy between the first floor and basement apartment.

She had a new granddaughter on the way, which gave a deadline for when the job had to be completed. She found a contractor who gave a very attractive bid, and she gave him two requirements - it had to look appropriate for an elegant 19th century Victorian house, and it had to be done before her new granddaughter arrived. The contractor said it would be no problem and took the bulk of the payment for the job up front.

Progress varied between slow and stalled. Workers showed up sporadically, often the only workers on site were seemingly unfamiliar with finish work, and sometimes there was no visible progress at all from one day to the next. The contractor showed up the day before the deadline to clean up his tools and install a bit of railing around the construction site so nobody would fall in the hole. There was no estimate for when the job would be completed, but there would be no work for a while with a newborn in the house.

With some time to think, the owner looked at the work so far and saw no sign of any plan - the style of construction could only be described as contemporary, completely inappropriate for the house. The construction quality was crude at best, and, as it turned out, outright dangerous. The center of the stair was a 6X6 fir post, the treads were 2" thick red oak - square edged, no details whatsover, and no attempt had been made to match the style of the woodwork that the staircase mated with. The whole affair was held together with seemingly randomly placed drywall screws and framing nails.

This is where I came in.


The wrong way:


This is the staircase as of when the previous builder was locked out of the job site. I had already started the drywall when this picture was taken.

The angles between the steps varies between 13 and 29 degrees. What had they planned on doing to fill the holes between the steps?

The two treads that end at the wall are sitting on short 2X4 stringers that are nailed into the wall with two nails each - three of those nail went into nothing but sheetrock. They are obviously moving when the treads are walked on.

This was supposed to pass for finish carpentry. Plain red oak from Home Depot in a house that is largely antique quarter sawn oak. No need to use one long piece of oak when you can use a couple of smaller ones. Note that the screws (drywall screws, of course) holding the landing on are not even in a straight line and have not been set deep enough to allow the holes to be plugged.

This is the underside of the landing at the top. Note the gaps at the ends of the diagonal studs.

This is one we were never able to figure out. They had chopped the middle out of this stud. Why?

Here is is from another angle. What was the idea?

The two bottom steps are sitting on short 2X4s, no idea if they were intended to be permanent. The next step up is held on with drywall screws.

The marble terrazzo tile was cut with a circular saw up up to where the front of the saw hit the wall, then it was finished with a hammer. All of the tile that came out was thrown away, no pieces were saved to patch the gap.

This is what was holding the bottom of the railing post in place - nails, and lots of them.



This was all of the job so far that was salvagable - just the hole. Nothing else could be saved.


The right way:


I closed up the open walls for insulation and to keep anyone from being injured on the exposed studs, and used the time given by the arrival of the new baby to draw up a plan. I tried to find a commercially available unit to fit the hole, but nothing could be found that would fit in the space (a 52" rough opening) and look appropriate for the house.

I settled on a design of a welded steel framework with wood treads. The steel would allow for a smaller diameter center pole, which was important - the rough opening was small enough that a couple of inches made a big difference. The center pole was 2 1/8" diameter.

The center pole is clamped in place.

Here are the first couple of steps in place.

It's slow work. The steel framing for the steps is firmly supported by the walls.

The top couple of stairs are going in. The steel hangers holding up the left side of the stairs are capable of carrying over 10000 pounds each.

Note that the first two stairs descend before starting the spiral. This allows significantly more headroom as the stairs wind underneath. This is a problem with most spiral stairs - the stairs have to be very steep to get the required headroom. These were surprisingly comfortable for spiral stairs.

All of the steel is in place now. Note that the wall has been patched. The drywall was set back a few inches to get every possible inch of clearance when going down the steps.

Some more drywall...

This is the start of the finish wood work. Quarter sawn oak was used to match the wood in the rest of the house and was later stained to match. The exposed edges of the wood were routed to match the profile of the other stairs in the house.

The risers are now on.

Into the home stretch - closing up the ceiling.