Saving energy and water :: Pipework

An interesting thread.

Long +/or copper pipes mean that the amount of water that needs to flow to a tap, before you have a hot tap can be a lot. Shorter plastic (that don’t absorb the heat, until they heat up) pipes will have a big impact on reducing the amount house users will run a tap in order to get their hot water needs / desires.

Also discussed is having thinner diameter pipework. If you have enough pressure, this means there is less water sitting in the pipes between times the hot water is requested. Suggestion is 12mm pipework.

Nice look & feel :: Bathroom

Some more inspiration from Houzz:

Nice bathroom wall tiles (but would this be a pain to maintain, clean etc ?):

This double sink setup is nice, but how about bamboo for the surface and not glass. More eco, will show marks less and could tie in with a bamboo flooring ?
  • Could have the same bamboo for the kitchen worktops and the bathroom surfaces ?

Possible shower wall idea

Potentially great alternative to tiles for a shower wall !

100 Ensuites to Inspire contemporary bathroom
and could potentially have the glass made from recyled materials !
  • Internal wall / surface sheets from recycled glass
  • Decoran glass ceramic, formed from 100% recycled float glass, is a revolutionary and highly versatile material, with the combined characteristics of glass and natural stone. Primarily aimed at internal applications as an interior cladding material, offers either the warm opacity of natural stone, or refined, contemporary levels of translucency – and even transparency – coupled with an unrivaled anti-stain quality and durability.
    Decoran glass ceramic is the luxury solution for interior and non anchored applications, including internal linings, feature walls, kitchen and bar surfaces, flooring and stairs, memorials, screens, vanity tops and sinks, and should be specified as a stone slab material.
    With a competitive edge over translucent stone rival Onyx, in terms of price, sustainability and evenness of colour, glass ceramic has unrivalled anti-stain qualities, as well as highly enviable environmental credentials, as no resins are used in the bonding process. Instead, glass crystals are heated to a sintering point and then control-cooled.’

EcoBuild: Toilets (waterless urinal & sensor on water tap)

Two toilets and a commercial tap sensor stood out at the Ecobuild expo:

One of the efficiency and eco objectives is a house that is water efficient.

Two slides, from different sources on domestic water use / water consumption:

My initial straw polling, is getting a strong reaction to the idea of a urinal, let alone a waterless urinal, from  at least 50% of the girls reacting!

Waterless Urinal

This has the potential to drastically reduce the amount of water used in the house.

They are marketed as “clean, green, odour free and waterless”.

I had it all explained to me on the Odourwise and Twyford stands. The module that fits into the bottom of the urinal converts all uric acid to a form that prevents lime scale, clogging up the system, takes away the smell etc. It seems that urine and water are a big source of limescale and other loo waste pipe problems, hence trying to dilute this away with (usually) lots of water.

All you need to do, is a few times a year (depending on use levels) replace the cartridge. In this photo the plastic bit on the top is the device to extract the Odourwise bit so that it can be replaced with a new cartridge.

A google search reveals there are a few alternatives, so more research needed.

My current thought is a urinal in the bathroom  off the main living area and also one in the bathroom off the study.

Also on show at Ecobuild 2012 will be the Odourwise™ Waterless urinals. Twyford Bathrooms offers the revolutionary Odourwise™ Waterless system for two of its urinal ranges, Centaurus and Galerie Plan. Centaurus is the first hybrid urinal that is truly waterless, combining maximum water savings with enhanced hygiene. The cutting-edge Odourwise™ Waterless technology requires neither chemicals nor electricity, keeping it eco-friendly as well as economical. The urinal is also entirely rimless, making it easy to clean (both within and outside the bowl). Installed with the Odourwise™ Waterless system, Galerie Plan offers the same cost-effective and eco-friendly benefits as Centaurus.

Toilet Sink Taps to be Sensor Driven?

Why use your hands to touch the tap to get the water flowing, before you’ve washed your hands ?

Why have the water running when hands aren’t beneath the taps ?

I need to check out the cost and any other implications. I assume they use a tiny amount of electricity, but best to check.

Combine the Sink and Loo ?

This great combined unit captures (there is an optional bypass if you don’t want it to, eg if you’ve cut your hand) the water you use to wash your hand and then stores this to flush the loo. Integrated 1 unit grey water system.

BUT, £2,500 !!!!!

I’m pretty sure I can have an entire house grey water system for a similar amount.


EcoBuild: Waste Water / Drain Water / Shower, Heat Recovery

At Passivhaus levels of energy efficiency hot water accounts for more energy than space heating.

At last weeks Ecobuild, I saw a couple of systems that do this. They capture the heat from hot water that is going down the drain and feed it back into the hot water system. It seems there are 2 systems:

  1. A vertical pipe that the hot water flows down, usually slowed, around the cold water mains supply. Their is heat exchange from the waste water to the cold water, that, in these systems typically, feeds into the water heater / hot water tank.

  2. A system linked to just the shower. So that the heat in the shower waste is immediately put back into the shower. As most showers have a thermostatic valve, this means an instant and guaranteed gain.

+ & – Thoughts

Check the cost of the system Vs the predicted and probable saving for an evaluation of how long the system will take to pay for itself.

  • One of the 2 systems at Ecobuild was the, €299 retail price, system, that you can see at So price wise, VERY worth considering,  but need to see if:
    • Have to use, what looked like, the integrated shower tray cap / valve bit, or can this work with any shower tray and it’s drainage inlet?
    • Will it cope with sand if used as the post surf outside shower?
    • What is the cost implication of this on each shower Vs a system that copes with multiple showers and other hot water drain pipes (bath, washing machine, dish washer).
    • Does it reduce the cold water pressure? (Does this matter ?)
      I’ve emailed Zypho these questions 
    • Nice write up on the Zypho unit at Ecobuild on the HardHouse blog by Mark.
      – looks good, but questions the heat exchanger and it isn’t yet fully UK approved.
  • Cost Implications:

If used for an external, post surfing, shower, will the system cope with sand, mud, dirt etc?
– it does look like the  Bristol based shower tray system could be put in post a sand trap !
– could even have this bit under the floor in the house and not outside where the cold, frosts etc. could be a problem. It could then also link in to the water outflow from the washing machine, dishwasher and any other ground water outflows of warm / hot water.

It seems that if you could get a single whole house heat recovery system that auto feeds the cold water supply to showers, and if they aren’t being used sends the preheated cold water to the water boiler (if it’s not full) would be the best. See the schematic below from

This is also how it’s been set up in the schematic at Bristol (UK) based
 – also see animation they have at$FILE/ShowerSave.swf

UK Water Heat Recovery Supplier Listing:

Test Data for Recoh Units:


  • Recoh-vert 61.2% efficient, with a mixer shower
  • Recoh-tray is 46.9% efficient, with a mixer shower

Shower-Save is even more efficient with a low flow rate or electric shower:

  • Recoh-vert 64.0% efficient with electric or other low flowrate shower
  • Recoh-tray is 52.6% efficient with electric or other low flowrate shower

Schematics of Waste Water Heat Recovery Systems

Notes from other Websites re these systems:


  • Typically, 80–90 percent of the energy used to heat water in the home goes down the drain. Heat exchangers capture some of the heat in drain-water, allowing it to be reused by incoming water. One type, called a gravity film exchange drain-water heat recovery system, has been found to save 25–30 percent of total water-heating energy needed.
  • This technology is compatible with all types of water heating systems, but it is especially suitable with on-demand water heaters and solar thermal systems. Prices range from $300–400 and paybacks are in the range of 2.5 to 7 years, depending on how often it is used.


  • Falling film heat exchangers have been around for decades. Other than utilizing the “falling film” effect, however, the Power-Pipe® has little in common with other Drain Water Heat Recovery (DWHR) devices.
  • First generation units suffer from high water pressure loss in the freshwater supply, which causes flow problems. Second generation units resolve the pressure loss issue by adopting a non-counter flow heat exchanger design, which delivers a low heat transfer performance.

Other Water Heat Exchange Systems & Discussions:

From Earth Save Products (bottom of the page) their Heat Squirrel – 120ltr heat recovery vessel (for domestic waste water)

Change Your Behaviour – Bath water heat recovery

One behavioural solution to waste water heat recovery, is to just leave a hot bath, hot sink of water full to cool down and transfer it’s heat to the room(s) before you pull the plug. How often do we pull the plug on a bath of hot water to let that heat head off down the drain, when we could let it cool down (ie heat the interior or the house) first ?

Mirror ideas for sinks that look out at the sea

Conventionally there is a mirror in front of the bathroom sink.

BUT, I’m going for a waist(ish) high wall behind the bed, with the sink(so) behind this.
So where to put any mirrors, that at some point you’ll need for shaving etc.

The Scarlet Hotel have wall to between waist and chest high. That makes sense in terms of a barrier to splashing etc. onto the bed.

– I also want the wall behind the bed to be at least a foot thick so that it can contain an alcove / cubby hole into which your normally bed side books etc. can go. That’ll mean no need for bed side tables and so more space for a wider bed +/or more space to the side of the bed.

Post Original Post Comments:

  • It’d be good to have other full sized mirrors in the bathroom, to reflect the view and light. But is there a good spot to put one.
  • There is the idea of putting a full size mirror on the back of the door from the dressing room (behind the bathroom) to the loo (off the dressing room). So that when the loo door is closed the entire back of that door is a floor to ceiling mirror.

Here’s a photo of the Scarlet Hotel mirror and then some others I’ve found:

There’s something to be said for the most simple and low-tech approach. A freestanding makeup mirror keeps this window entirely unobstructed for sunshine and the view. What a cheerful spot to start the morning.

Or some designer thing?
Not sure if it’ll work in the room, but the idea of cables / chains to hang a picture mirror down appeals !
This could make it easier to put a heated panel on the back of the mirror to keep it from steaming up ?
Which could be even easier if the mirrors were on pipes to the ceiling.
– which could allow the mirrors to rotate, but that could cause it’s own problems.
Evolving the above mirrors, and adding in the idea of these being mirrors on both sides:
With a half height wall between the bed and bathroom area for the 2 sea side bedrooms, the idea is for mirror(s) that are in this open space:

front bedrooms from outside

The above photo from the SketchUp model shows how you can see from the bed, back into the bathroom areas.

The current idea is mirrors that are on supports from above and below:

double sided mirrors - from inside - mockup

The sinks and storage will probably be different from the above mockup.

From in the bedroom, these can be mirrors on the other side, so that in the bedroom area, they are mirrors of the view out to the sky and sea:

double sided mirrors - from outside

Shower and Bath details


Towel radiators for warm dry towels.

Under floor heating (will be house wide anyway, but make the bathroom areas on their own circuits.

Drawer(s) that have integrated power sockets for hair dryer, elec toothbrush etc.


Put shelves in the shower walls to put shower stuff. Also have one at a hight good for girls that shave their legs in the shower.

The shower(s) should have a hand held shower nozzle. Whether additional or not to the main shower head. The shower below has a separate shower nozzle and a wide high shelf (that is therefore less likely to get and stay wet.)
– it’s make sense for the shelf t to have no grout (be one piece of something like slate or marble) and to also have a slight slope into the shower.

shower niche shelf

Have a look at how to place shower controls & the idea of a glass shower wall.


Also like the idea of shelves on the wall behind the bath (depending on where the bath goes)

RUSSIAN HILL modern bathroom
Aquamar Bathtub modern bathroom

Nice bath shape and works for 2 people having an end of the bath each.

Scarlet Hotel bathroom behind the bed (that has a view)

The Scarlet Hotel have maximised the space and superbly put the bathroom behind the beds, so that you look out over the wall, over the bed, out the window and over the beach and sea 🙂

Even if you only pop in for a drink, do go by the Scarlet Hotel / Bar / Restuarant / Spa ….

I should this week be going to a talk by Surfers Against Sewage founder Chris Hines, who worked with the Scarlet creation team:

Along with Alistair Sawday, Chris Hines was a key part of a small team who brain stormed the sustainability and function of the Scarlet Hotel. The end result is wonderful!

16 Nov 2011 – Update / Extra bit

Saw this picture (below) and thought there could be a wall behind the bed (that faces the view) that has a window with glass, or a cut out hole through from the bathroom behind the bed.

Also, another pic in the direction of the bathroom behind the bed. Taken from a house in Camps Bay, Cape Town:

I assume this bed has a bathroom behind the wall and that it has a view:

Natura Night Stand modern bedroom


8th March 2012 – Update / Extra bit

Robert and I visited The Scarlet to have a look at the general architecture, features and to rough measure up the rooms. To see if some of the concepts will fit for the 2nd bedroom at Silver Spray.

Bedrooms 2 & 3 at Silver Spray are quite a bit narrower than the Scarlet – approx 3.2m v 3.8m (in the Scarlet), but I think will just about work.

Note position of the towel rail and mirror by the sink.