Houston, We Have a Problem!

Remember me saying yesterday about the weird vertical wooden slats? Well I decided to take one out to see what lies beneath. It wasn't what I expected. I thought that maybe I would see studs, but instead, there is a wall of horizontally-laid wood. Looking closer, I see what appears to be studs behind that, and further back still is presumably the exterior wall (you can see part of the stud in the picture below).


I don't know what to make of it, except that maybe what I'm seeing is the old exterior wall, which means the studs and beyond (which look newer and cleaner) were added in a more recent renovation.


The problem I have is deciding what to do now. I cut out a small section of the plasterboard and as you can see in the photo, the top half is plasterboard (or drywall?) over horizontal straps. If I take out the lower part down to studs, I'll be almost 2 inch deeper than the straps above, so I may have to take out the whole "old wall", top to bottom. Then I'll also have to refit the window, or at least get a new frame.

My current thought is to stop at this point instead and to add straps (either horizontally or vertically) over the bottom half, so that the surface of the new straps on the bottom is level with the old straps on the top half. Then I'll leave the top half of the wall untouched (except for sanding and filling the old plasterboard), but I'll cut out a strip of the old plasterboard (so I have an opening the length of the wall (7'7") and 4' high and then I'll fit a sheet of drywall in the gap, horizontally, and screwed to the new straps. This board will butt against the old plasterboard on the top half and I can join them like regular drywall. Right?

Can I do that? Leave the plasterboard at the top and add drywall at the bottom? Are they the same thing? Will they "bond" together? Should I take out the whole wall instead?

Time left: 58 hours.

Jobs left:

• Cut off water supply and remove fixtures (toilet, sink, bath and surround)
• Remove tiles
• Remove subfloor down to floorboards
• Remove wooden slat-type things on lower half of wall
• Remove any rotten drywall behind bath and surround
• Add straps to wall
• Fit subfloor (5/8" spruce 4'x8')
• Fit drywall
• Fit cement board
• Tape and paste drywall and cement board
• Sand drywall
• Fit bath
• Fit surround
• Tile floor
• Wait 24 hours for tiles to dry
• Grout
• Wait for grout to dry
• Wash grout off tiles
• Fit toilet
• Fit sink
• Seal bath, surround, sink and toilet
• Paint walls
• Add fixtures

I think we may have (and need) some grace in the timescale. This could take another week at this rate, maybe more. I'm exhausted and I already have enough plasterboard dust in my nose and throat to plaster a whole extension on the house! (Yes, I am wearing a mask and goggles when I remember, but that dust gets everywhere!

Please post a comment with your ideas. I'm stumped!