Building a Staircase: Design

The next stage of the project is to build the staircase that will lead up to our new 2nd floor (the loft). The loft was framed out over a two periods: just before we started the roof and just before we moved in; it sits over the bedroom, bathroom and kitchen.

Cut-away view from digital 3D model (used during design phase) showing how the new staircase leads up-to 2nd floor loft

Developed during our design phase back in the summer of 2010 (!), the staircase will consist of 3 parts:

• The first flight of stairs starts at the edge of the bedroom door (where the floor was extended) and runs up to a landing . This will be an "open riser" stair, meaning the vertical elements of the stair (known as risers) are gone. Because the stair sits over the entrance to our terrace (with glass doors), we did not want to block the light, so not having a risers will allow light to pass through the staircase.
• The second part is the landing, which is bolted into the exterior brick wall (just above the door to the terrace).
• The final part is the 2nd flight of stairs, which is turned 90 degrees and starts at the edge of the landing and goes up to the loft. Because everything is so tight, this second flight will pass through the bedroom after passing through the structural wall opening that was framed out yesterday.

While the design intent was established long ago, I only developed the actual detailed design of how it will be built over the last few weeks. These drawings were initially done by hand - once they were finished, I submitted them to Building Control (the London version of NYC's Building Department). After a few minor revisions, Building Control approved the design for structural integrity and deemed it compliance with the UK Building Regulations (similar to NYC's "Building Code").

3D hand sketch showing the structural elements of the staircase

This approved design details how the landing becomes a structural element that will be bolted into the brick wall on one side and fastened to the structural stud wall on the other. Because the first flight of the stair has no risers,  each tread (the horizontal "step") is notched into a large 2"x8" structural stringer (the diagonal element) on each side. This will make the flight incredibly strong while still allowing light to pass through. This flight is then attached to the landing using heavy screws and steel plates.

Section sketch showing the primary stringer and steel plate that assists in the connection to the landing.

One of the design ideas that made the stair more difficult to build was the idea of keeping the 1st flight a few inches away from the wall. The idea is to allow light to pass through this gap - both from the terrace door, but also from a light cove that will eventually built above (in the ceiling at the edge of the 2nd floor) - allowing the light to pass through should not only provide additional lighting for the stair, but should also create a great looking effect as the light washes down the wall.

From a structural perspective this mean that this 1st flight could only be held at the top and bottom, not also on the sides, as with most stairs. Because the landing is itself partially cantilevered, this meant that only through the combination of both landing and stair would the entire assembly actually be strong enough. This was achieved by allowing the primary stringer to be attached to the side of the landing using an additional piece of 2"x8" wood (creating a heavy angled "L" shape) that's stiffened by a heavy steel plate at the joint. This angled "L" shape will act almost like a column to hold the hanging end of the landing - this can best be seen in the section sketch (above) and plan sketch (below).

While everything looks good on paper, we'll soon see how it well it works in reality...

Plan view of landing and how 1st flight of stairs is fastened to it.

Sourcing Tiles

The bathroom construction has gotten far enough along that it's time to pick out and order tiles! This is a huge step for us, psychologically - if we're starting to select finishes, then it means we're finally beginning to see the light at the end of this long, dark tunnel of construction.

We have actually managed to accumulate almost four dozen stone samples! But (as with everything else related to this project!) it was a bit of a journey to get to this point...

The piles of stone tile samples

We had initially looked at tile over a year and a half ago, back when we were optimistic that construction would be relatively quick and painless, and before things got complicated. At that time, we had visited several tile shops in and around London, collected around a dozen samples and had picked out a few options we liked: dark(ish) porcelain tiles from Spain. But as the bathroom construction progressed, and after actually living in the flat for many months, I started having doubts about those porcelain tiles: they now felt too dark, and too "perfect". Considering how much character the ceiling now has and our intention to re-use the old wood floor planks, I had a gut feeling that we should go with a natural stone that was lighter in color.

Two types of slate from a supply shop in Vauxhall: a honed wine colored (left) and a riven-cut "oyster" ( right)

A type of limestone they called "Barcelona", but that was not readily available.

That meant starting the search for tiles from scratch. At least (having spent time doing it a year and a half ago), I already knew of a few good places - but I had forgotten how far away and how spread out across the city these shops were. As a result, I ended spending close to a week running around London collecting samples and determining availability.

Just outside the shop in Vauxhall - you can see the "Shard" under construction. Designed by Renzo Piano, soon to be the tallest building in Europe when completed

The showroom of a shop that specializes in stone tile - located on the edge of Southwark & Southfields

A showroom wall with different types of stone

A marble installation

Eventually we started to realize that "Aglaya" really wanted a colorful and varied stone, while I was gravitating towards a cleaner, simpler limestone. I had envisioned the bathroom as having two different stones: one for the shower area and another for the rest of bathroom. Because I was extremely taken by a warm toned limestone (with a hint of blue) called Batieg Azul (which came from Portugal and Spain) we started focusing our efforts on finding a second stone that would be more colorful but would also complement this limestone.

The Bateig Azul installed in a showroom mock-up

A detail of the Bateig Azul limestone

We soon decided that slate should be our second stone. I knew that there were hundreds of types of slate - in my New York office, we have several drawers full of slate samples from a specialty supplier there, but for some reason I could only find a few options in London. Eventually I found a specialty supplier of slate in Finchley (north London) with several dozen options, including a copper colored slate that "Aglaya" absolutely loved.

Once we returned to the flat, we were pleasantly surprised to see that the copper slate really worked well against the limestone. We slept on it for a few days, tried other options, but the combination of copper slate and Bateig Azul remained our favorite.

The honed Copper Slate on top of the Bateig Azul

We decided not order the stone before I return to New York, but "Aglaya" can place the order a week before I return to London again...

The Shower: Initial Build-out

While the plumber was installing the radiators, I was able to start focusing my attention (finally) on the shower. It (along with the rest of the bathroom) is going to be completely new - when we did demolition we pulled out all the old fixtures, so for the moment, the bathroom is just an empty space except for the toilet and the boiler. So the entire shower enclosure has to built from scratch: framing, walls, floors, waterproofing, tiles and new plumbing...in other words, "the works".

I had previously installed the bathroom sub-floor, working out the initial layout when we had the boiler installed. During that period, the wall separating the shower from the boiler was put up - so when everything is finally done, that wall will become the front of the shower (where the shower head and valve go).

Morning of October 17th - the previously framed-out is visible on the left.

After clearing everything out - the starting point for the shower!

The first task will be to start installing the tile backer boards - I had done quite a bit of research on the various options and decided to go with a product made by Marmox - a waterproof, insulated cement board. Not only will this be the proper surface to which the tiles can be attached, but it can be used as part of a waterproof system for building showers - I liked that this product accomplished several things at the same time. The Marmox boards can either be screwed into framing, adhered to masonry with adhesive, or nailed in place with plastic "spankers". I opted for using the "spankers" and the adhesive due to the very uneven surfaces of both brick and plaster - this was similar to dry-lining plasterboard in the living room. The adhesive itself is waterproof, but it also adds strength to the installation which will be necessary if we use heavier stone tiles.

Applying adhesive to the wall and the back of the Marmox board

The first Marmox board installed

The design for the bathroom (and specifically the shower) ended up becoming quite complicated as there are many "spanners" in the works here. You may have noticed there's a large arch in the brick wall - this was only discovered during demolition as it was hidden behind the old walls. This arch resulted in a steel post going in to reinforce the steel beam - which (of course) pockets into the brick wall directly above the arch. This post ended up in the shower, and the post is sitting on a heavy steel beam to help distribute the forces and weight (or to be more precise, the point load) of the post across a few floor joists below. As a result, the floor of our shower will sit on-top of the steel beam. I also added a ledge that wraps around two sides of the bathroom - this was initially done to help hide the concealed cistern from our loo, but i carried the ledge around to give a ledge over the sink and in the shower where we can put things. The final design of the bathroom incorporates all these elements and (hopefully) will seamlessly tie everything together for a clean and simple appearance.

Second Marmox board installed and starting to frame out the base of the shower. The ledge is also starting to be framed on the right side of the picture

The shower base fully framed out - sitting on top of the steel beam.

The shower floor's plywood substrate

The Marmox system includes an insulated and waterproofed floor board that is pre-sloped for water drainage. I ordered one that was closest to the size of our shower and then cut it down to fit. One of the other things I liked about the Marmox system is that is has been designed around a specific drain - the floor board is pre-cut to receive the drain, so the entire system is integrated and should come together easily.

The Marmox floor board

We had worked out that as the plumber finished working on the heating, he would do the "roughing", or first fixing, of the shower pipes and fixtures. We had previously selected and ordered the shower head and valve, but that evening "Aglaya" and I had to choose exactly where they should be installed the following day - she really enjoyed this part!

Locating the shower valve - which height feels right?

Locating the shower head.

So the next day our plumber installed the pipes and fixtures based on the locations we selected the previous evening.

October 20th - Overall view of the shower plumbing

Detail view of the shower valve in the wall

The floor drain anticipating the future floor height due the steel beam (visible in the backgound). The white pipe is a condensate drain coming from the boiler

With the initial plumbing completed, it was finally time to sheath the shower with plywood, covering the pipes (on one side). As part of the waterproofing I decided to use WPBP (waterproof boil proof) plywood that would later be covered with a waterproof tanking kit (to be explained in the next post), followed by the Marmox board.

Installing the plywood substrate

Most of the plywood installed

With the floor, plywood, plumbing and Marmox in place...the outlines of a shower are finally starting to be visible!

The Design: Lofting a Victorian

 

When we first saw the flat, we had to really look past its dire condition (and the piles of rubbish) to see the potential. What really attracted my attention was idea of opening up the flat to the attic space - this also provided an opportunity to add a second floor, known in the UK as a loft conversion.

I knew straight away that I wanted to get rid of the ceiling and expose the wood structure that supports the roof - looking past the layers of dust, there was so much character, especially in the age and patina of the wood. Exposing the underside of the roof would also create a double-height, cathedral-style ceiling.

The Attic

The existing layout was awful - it would also have to go. So much wasted space! If the idea is to open up to the attic, then the plan would have to be opened up, and simplified. The living room space could be enlarged by re-locating the kitchen closer to the bathroom. This would effectively put all the “closed” room together as efficiently as possible into a single volume tucked under the 2nd level...you could almost say we’re lofting a Victorian flat...

 

Final Design - View from Dining Table

The trick to this became making everything fit into as small a area as comfortably possible so as to maximize the open space. As is often the case, it all came down to the bathroom and kitchen...and in this case it was all about the kitchen. After many sketches and schemes, I realized that the kitchen layout would be determined by the clever arrangement of the appliances...and that was about it--there was no extra space! The compact layout is hidden by losing two of the kitchen walls, opening the kitchen to the living area and adding a bar counter--which would help hide the “stuff” of a kitchen, as well as provide additional counter and entertaining space. Once this was worked out, the resulting dimensions set the wall of the living area, and the bathroom layout fell into place. 

Final Design - View from Living area

Final Design - View of Kitchen