Showing posts with label structural wall. Show all posts
Showing posts with label structural wall. Show all posts

April 3, 2012

Rebuiding "The Box"

With the structural wall re-framed and the floor extended, the entry and walls to the bedroom are mostly framed out and we're almost ready to have the plasterboard (called Sheetrock in the US) replace the temporary plywood walls. It's because of these plywood walls that we call the bedroom "the Box" - since we moved in, the "bedroom" has been enclosed by plywood, making it look like a "box". But today...that's going to change!
The re-framed structural wall and extended floor in-front of "the Box"
The first thing that needs to be done is some additional minor re-framing of the structural wall (also one of the bedroom walls) to create an opening where the new staircase will pass as it goes upto the loft (2nd floor). This work was left until today because in order to do it, I'll need to remove all the plywood. Taking down the plywood was technically easy to do, but psychologically, this is a very big deal for us - we've been living with it for over a year, and this is the first step to returning to some level of normalcy.

Temporary plywood walls of "the Box" (photo on the left) - a few minutes later, the first few panels removed (on the right)
All the temporary plywood removed from the re-framed structural wall along the bedroom
With the plywood removed, I was able to easily cut out the opening and set a new wall-plate that will act as a structural anchor for the new staircase. This completed all the re-framing work and I could now begin re-sheathing the walls.
Cutting out studs to make an opening for the staircase
The completed opening
 The re-sheathing of the bedroom began with adding plywood - but this time it's permanently attached to the exterior face of the structural wall. This plywood is being required by our official from Building Control (the equivalent of the Department of Buildings in NYC) to make the wall extra strong and stiff so that it acts as what's known structurally as a diaphragm system. The entire wall is sheathed in structural plywood and fastened every few inches with screws. Later, this will be covered with plasterboard and painted - eventually it will be blended in and hidden.
The first piece of structural plywood added
A few more pieces of plywood seen from inside the bedroom. The opening for the staircase is on the right side
The completed plywood seen from outside the bedroom - the door opening is again visible.
Once the plywood was completed, I shifted my attention to the other walls so as to hang the plasterboard. Before any plasterboard could be hung, the wall that separates the kitchen from the bedroom needed to have the final studs installed. These were quickly cut, placed and leveled.
The remaining studs installed at the side bedroom wall
Once the studs were in place, it was finally time to start hanging the plasterboard. I hung one board on the side wall just to see how everything fit together, and then quickly insulated the structural wall before covering it with plasterboard. All the walls will be insulated to help with sound dampening and to retain heat within the bedroom during the winter.
The first piece of plasterboard in the bedroom!
Insulating the structural wall.
Hanging plasterboard is quite not as basic as it sounds. Building control requires us to maintain a 1 hour fire rating around the bedroom, which can be achieved with either 2 layers of regular 12.5mm (5/8") plasterboard or one layer of special fire-rated plasterboard - which in the UK is, funnily, colored pink (to make it obvious the board is rated). Here I decided to use the pink (rated) plasterboard along the structural wall (because it won't have much traffic/abuse) but two layers of regular board on all the other walls (so they are stronger and can take more abuse & traffic).
A few more boards up - the pink (fire-rated) plasterboard on the front wall with regular board on the side wall.
Most of the plasterboard hung
The plasterboard went up rather quickly - but by this point it was late, and I was getting tired after a 12-hour day of labor. But the plasterboard made a huge difference in how the room felt - the plywood is gone, and our bedroom is finally starting to feel like a real room rather than a plywood box!
End of the day - the bedroom re-sheathed in plasterboard

March 28, 2012

Structural Wall Surgery

While the extending the floor, I was somewhat simultaneously re-framing the only remaining Victorian-era structural wall left in our flat so as to accommodate an opening for the new bedroom door. This door location is only possible because of the floor extension - the new door is squeezed in between the top of the old staircase, the kitchen and the beginning of the new staircase that goes up to the loft.

Perspective from 3D computer model used in the design phase - the new bedroom door and new staircase (upto new loft) meet at this critical location adjacent to the new kitchen

This arrangement was developed in the design phase when it became apparent that in order to open-up the space, yet maximize the size of the kitchen and bathroom, we would have a very tight convergence at this very location. This convergence makes the floor extension and relocation of the door critical to the new layout. At the time it was not obvious this wall was structural (it supports a post that helps hold part of the roof) but having worked previously on this wall, and reviewing the proposed work with building control, I felt confident moving forward.
March 27th - The original Victorian-era structural wall (plaster was removed during demolition)
The "surgery" involved cutting through the existing studs to create an opening that will fit the future door. As in all structural work of this kind, the most important thing is to brace the areas of the wall that are doing the structural work so that the wall does not "know" that you're re-arranging it - it's almost like a magic trick. If the structure realizes what you're doing...you're in trouble...

So the first step is to brace the beam at the top of the wall (known as a wall plate) that is actually carrying the weight of the roof post above it (that helps support the roof). The brace is rather simple - a heavy stud (old growth wood from the original roof) that sits on top of temporary beams that span the opening in the floor for the stair.
The temporary brace to support the wall-plate while structural work occurs
Once the brace was in place, I began to cut away at the studs and re-frame the wall to accommodate the opening. Because this wall is one of the bedroom walls, I did this work keeping the plywood sheathing in place, since the plywood acts as the temporary walls to the bedroom, keeping the dust out. But this made the work more difficult, so I had to go "old-school" and use a handsaw...
Cutting and removing the first pieces of the wall
Using a handsaw at a tight spot where power tools would not fit
The opening is done and new side studs repositioned...all that's left is horizontal member at the top of the door opening
Once all the members that were in the way were removed, I was able to reposition the vertical studs (doubling them up on one side for more strength) and then finally add a double "header" at the top of the door opening. A header is the horizontal member at the top of a door - because this wall happens to be structural, this header is structural and will do the primary work of transferring the weight, or "load", of the roof post to the rest of the wall.That's why the header is doubled up and additional vertical members are added using steel clips to ensure their position and strength.

Once everything was in place, I held my breath and removed the temporary brace...all is good!

The brace is removed and the newly re-framed door opening is complete
Before & After montage. On the left (before): the structural wall and floor - On the right (after): the extended floor with the new door opening

January 26, 2011

Loft Framing (Part 2)

In anticipation of moving-in tomorrow, we're trying to finish framing the loft floor so we'll have a ceiling above the temporary bedroom. Because of everything that's going on (patching brickwork and  waterproofing the roof ) we were only able to start this work in the early evening, which mean that we had to rush before it got too late.
Jan 25th - the partially framed loft and original structural stud wall
To complete framing the loft, we have to add new joists that are perpendicular to the original loft joists we set last month - these new joists have to change directions in order to accommodate an opening in the floor for a staircase that will eventually come up-to the loft. 

To accommodate this change in direction, these new joists will hang off of a double beam (on one end) and will sit on a structural stud wall at the other end.  Before setting these new joists, the top of the structural wall has to be shortened to the correct height, and a new wall plate (horizontal member) has to be set. This wall plate is what the new joists will sit on.

Trimming the top of the structural wall
Once the new wall plate was set, we also set a new full length beam that will act as the edge of the loft/floor. After this beam was in place, we were finally able to hang the smaller floor joists  using steel brackets.
Setting the first few floor joists on the structural wall
The next morning - a partially framed floor
Adding the remaining joists
By the end of the day we were  able to start fixing the plywood sub-floor...proving a ceiling to the temporary bedroom. While we were not able to completely finish the plywood sub-floor, it will be enough to get-by...at least for now....
Checking everything is lined-up before starting the plywood sub-floor
Fixing the plywood sub-floor to the joists