To start off, I remeasured the horizontal and vertical distances that the stair case will need to traverse.
The "as built" measurement agreed within a millimetre for the horizontal distance and it looks like the landing has pushed an additional 10 mm in to the void space.
Next I turned my attention to removing two purlins under the street level floor to allow me to establish the staircase header.
I cut an access hole through the temporary particle board floor and removed all the screws holding the floorboards to the purlins.
Then I removed all the bolts and tek screws holding the purlins to various bracket and the stud frame / beam under.
I need to attack the purlins with a reciprocating saw or angle grinder next.
The process is complicated a little by the presence of electrical cables running through the steels.
We have just had heavy rain today so I might be safe to use an angle grinder for the first time this year (is the fire season over ?)
I might also ask Linda to watch over me and hold a hose while I do this.
On my next visit I will need to take acro props to hold up a section of the floor while I substitute in a substantial PFC beam to create the header face.
Using a combination of angle grinding and the reciprocating saw I managed to remove the purlin.
There was a 20 mm section that I could not reach and I had to drill this out.
I then placed an acroprop to lift the floor boards to allow sufficient room to insert the support beam.
However I was restricted at the edges by some boards that need cutting through.
My existing multitool is out of action and I have been told that there are only 2 locations in WA for servicing Bosch equipment.
I really need a working multitool for Wednesday so I visited ToolMart in Midvale and bought a Makita, line version.
I also bought a fairly expensive wood cutting tool piece.
The multitool had to be ordered in from another branch, so first thing, I needed to head down to Midvale and pick it up.
Once out on site, I immediately tested it.
I had about 1.5 metres of floorboard to cut through and I was not expecting any great joy from previous experience using cheap cutting tools.
This tool surprised me and cut very quickly for the first metre and burned its way through for the remaining - which was a better result than anything I expected.
Once the floorboards were liberated on either side I found that the acroprop could very effectively give me enough clearance to rorate the steel beam in to position.
I marked up a number of bolting points on the beam while it was in situ and then used a genie lift to remove it temporarily.
I then had to spend several hours drilling new holes and cutting out sections of steel.
When I reainstalled it everything dropped in to place perfectly.
I then had to play around with packers (washers), at each end, for a couple of hours to plumb it in vertically.
Jim and Sandy turned up at this stage and watched (and helped) as I bolted on the descending brackets.
Next I need to cut a 30mm thick piece of ply wood to length to install the hanger plate.
Hopefully I will be free to do this on Friday.
I installed the hanger beam and then used a plumbob to mark its position on the floor and measure it distance from the landing.
There is a variation of 7mm from one end to the other but I will have to live with this somehow.
Next I used a multitool to trim off all the floorboards above and then I removed one the purlin that was no longer covered by flooring.
First, I took the stringer template that had already been created for the level above.
I wanted to see if I could be lucky and use it from basement landing to street level.
However, it was slightly short and rising slightly too much to be a good fit.
I embarked on a new set of calculations, marking out and cutting.
This took quite a few hours.
The fit was reasonable but not perfect - I will live with this
From this I could see how I could notch out the string at both ends and support it on 45 x 90 timbers attached to the hanger boards.
This all needs a bit of fettling on my next visit.
I will use this template to create a sister test stringer.