The Shower: Waterproofing (part 3)

After an interlude with tiles,  insulation and pigeons, I'm finally getting back to waterproofing our new shower. With the Marmox backer board installed at the brick wall, it's time to start waterproofing the plywood walls so we can put the Marmox boards on them as well.

As previously mentioned, we're using the BAL tanking system on the plywood. It's straightforward work, but rather time-consuming...

Dec 9th - starting to waterproof the plywood substrate

The plywood fully painted with the waterproof membrane

A detail showing where the shower valve sticks out

The polyester tape applied at the plywood joints

All the plywood walls are now waterproofed!

Now that the main plywood walls are waterproofed, I have to deal with encasing and waterproofing the steel post. The problem here is - how to fasten plywood to it? If I had some of  my steel-fabrication tools here (I used to build steel furniture in NYC), it would have been easier. But since I don't have that stuff (and since it wasn't worth buying a load of kit when we would only use it once), I had to get creative. I ended up using some of the large 150mm screws (6") that were left over from the structural roof work to make a sort of plywood sandwich! This meant the plywood was fastened to both sides of the post using these long screws (going through the post) to hold them together.

Dec 10th - drilling holes for the large screws

Setting the first piece of plywood (on the far side)

Adding the second piece

Now we have our plywood & steel "sandwich"

With the post sandwiched in between plywood, it was then possible to finish framing out the rest of the corner, including the shelf...

Dec 11th - the shelf is built out

With the plywood work finished (and the waterproofing membrane dry) it was finally time to attach the Marmox backer board. Similar to the brick installation, one uses large washers, but here, we use stainless steel screws rather than the plastic "spankers". As before, the joints between boards are sealed with silicone and then taped over with a waterproof tape.

Starting the Marmox board installation on the plywood

The silicone sealant applied to the joints

The waterproof tape goes over the silicone joints

The stopping point - before catching my flight back to NYC...

Floor Insulation & Pigeon Patch

After we realized that there was no way we were going to finish the bathroom construction before my return to New York (because of the time needed to order and deliver the stone tiles), I decided to take a day to deal with a few small tasks that were becoming more and more pressing...particularly as the weather was getting colder and colder.

Back when we leveled the floors at the beginning of the year, we did not install insulation. But now I feel strongly that we need to start making the flat more comfortable - not just bare-minimum livable - so with the temperature dropping and some drafts becoming apparent, it should be done soon. Plus - with the radiator plumbing completed in the bedroom we no longer need access to the floor, so it's good time to do it. After some research, I ordered several very large bags of insulation...

The insulation being delivered

The bags of insulation are quite large!

In addition to the insulation, we also needed to patch a hole in the rear exterior brick wall. This hole was the result of removing the old waste pipe from the original bathroom - it was removed during the plumbing's first fixing - right before the scaffolding was taken down at the end of July.

The "hole"

Not only did the hole let cold air into the cavity of the floor (a big source of drafts in between the joists), but we learned very quickly that a pair of pigeons had moved in! The pigeons did not bother us at all (they were under the floor and off to the side)...in fact "Aglaya" thought it was quite sweet to wake up every morning to the sound of their cooing (and they were LOUD!) But they really bothered a few of our neighbors. Because this would be a messy job (with the bricks & mortar), I figured it would make sense to patch the hole on the same day the floor was insulated.

After removing part of the closet and cutting away the floor boards

The view from the hole (you can see one of the floor joists on the left)

Patching the hole involved making mortar and fitting pieces of brick which meant cutting them individually. What made this difficult was having to work from the inside as there was a 3 story drop below. I should point out that this could not have been done when the scaffolding was up as it did not reach this far over...

The patched hole - sloppy but done

Once the patch was completed, I moved onto the insulation. This was a relatively easy task, but (as usual) it took a bit more time than expected. Having recently been involved in a sound proofing project in New York, I wanted to be sure our floor also provided a decent amount of sound dampening between us and our neighbor below. A key element in sound dampening is to have insulation, but it's better if there's an air gap, so I decided to raise the insulation a few inches above the plaster ceiling using chicken wire to prevent it from slipping. The chicken wire was what took a little time, but within a few hours I had it completed...

Removing the plywood sub-floor to expose the cavity between the joists

Installing the chicken wire between each joist (prevents the insulation from slipping)

Half the insulation installed

The completed insulation

That night we noticed that "the Box" was significantly warmer and the drafts had been minimized...mission accomplished!

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...