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Bathroom Design

Star Making a stylish bathroom that is totally waterproof so there is no mold.


Bathroom and shower walls and floor

Shower floor

You will also need to form the thinset for the floor so water flows to the drain.  There are various mechanisms available for getting the slope profile correct.

Shower floor former Details are here .

Under the tiles needs to be Ditra.

Waterproof Wall Membrane

To waterproof the shower it is best to line the walls of the whole shower cubicle with Kerdi membrane.  This is plastic but with a furry lining on both sides to make the thinset stick.

Kerdi shower install    Details are here .

Waterproof floor membrane

Use Ditra (which is like Kerdi membrane but also provides mechanical decoupling between the tiles and the floor structure).

Schluter Ditra  Purchasing details are here .


It's best to use porcelain tiles (rather than ceramic). 


Tile Mural

And for the finishing touch in the shower you can have a nice picture done in tiles in addition to regular porcelain tiles.

Shower tile picture 

Details are here .



Position it and make it big enough so that both tall and short people can see their face and hair.


Bathroom Light

Bathroom Light Strip Hampton Bay 6 Bulb Details are here .

The light is typically a strip of lights mounted over the mirror.  People look better when using warm color (yellowy) light bulbs but it is more realistic to use cold color (bluey) light bulbs.  You could decide to put a light strip above that is warm bulbs and strips down the two sides of the mirror that are cool bulbs.

It is best to use LED bulbs because they last longer and are more energy efficient if left on accidentally, but some people like using incandescent bulbs because they warm the face and help dry the condensation on the mirror.

Bathroom light roughed-in 


Light switch

The switch (or switches if providing both warm and cold lighting) should be outside the bathroom (where it is dry).  It should be a home automation switch (eg Insteon) so that someone using a waterproof tablet in the bath is able to control the light, eg dim it.


Extractor fan

Instead of using an extractor fan it is far better to suck the warm moist air from a bathroom into an HRV (Heat Recover Ventilator).  I use an HRV.  The HRV will be running continuously so will clear the steam from the bathroom even when you are in the bath (whether you want it to or not).

Even if using the HRV method it is still sensible to provide a hole in the concrete wall to allow for the possibility of an extractor fan.  An extractor fan can be useful for dumping heat on a hot day.  I provide an extractor fan, but only use it in the summer.

Extractor fans should be used with a timer switch so they operate for say 15 minutes after you leave the bathroom.  Put the timer switch outside the bathroom (next to the bathroom light switch).  Put a note on the switch saying "Only use extractor fan on hot summer days" or you will be wasting energy.

You can implement a simple extractor fan by putting a duct fan in a round hole in the concrete wall.  (The wiring in the following picture is only temporary and does not meet building code.)

Extractor fan bare concrete 

Extractor fan grill

Power outlet

You need a power outlet for hair dryers and razors and by code it must be a GFCI protected output.  It is best to make it a waterproof external GFCI outlet so it can stand being squirted by the shower.  Put it up high, eg at about 5 feet to try to keep it away from shower spray.  The power to the bathroom GFCI socket must be raw power and not already protected by some other GFCI (you never want two GFCIs in series).


Access panels

It is necessary to be able to get access to things such as bathroom U bends, sink U bends, emergency water turn-offs, spa pumps, etc.  A good way to do this is to use a large porcelain tile in a recess with a rubber self adhesive seal round a lip inside.

Underfloor heating

This adds a lot to the feeling of comfort in a bathroom.  This can be PEX pipe with hot water or can be an electrical heating mat.


Heat lamp

This is a special infra red bulb mounted in the ceiling.  It is worth considering if all the bulbs round the mirror are LED.  It is a good way of heating up a bathroom before going for a bath.  It needs to on a home automation relay switch (eg Insteon) so you can turn on the bulb from your armchair 30 minutes before going for a bath.


Bathroom accessories


Shelves need to be waterproof.  You can make shelves using tiles that are top and bottom and stuck with thinset.

Chrome bathroom shelf bracket

Chrome bathroom shelf bracketPurchasing details here .

Towel rack

Ideally this should be heated, eg by running hot water through it and it being a radiator.


Toilet Roll Holder

Toilet roll holder Purchasing details are here .


Robe hook

Robe hook Purchasing details are here .


Towel Bar

Towel bar Purchasing details are here .

Medicine cabinet

Should be recessed into the wall.  When the interior walls use 6" framing the cabinets can be 6" deep.

Magazine rack

Not something I personally like in a bathroom.

Big fan

This is to blow dry your whole body after a bath and to cool you down on hot days.  It is best to make this a portable 20" fan that can sit on the internal window sill next to the open window.  It blows into the room.  It is nice to provide a power outlet from the bathroom GFCI near the window for this purpose, with a simple Decora switch next to it.

Fan - 20" portable Details are here .

Media entertainment

LCD screen, PC, and remote control keyboard.