EcoBuild: Air Source Heat Pumps

Air Source Heat Pumps

The installers / advisors to projects that were speaking at the lectures for self builders were all very positive about air source heat pumps in terms of how they work and how they stack up from an environmental / energy / sustainable point of view.

There are now automated systems for (for example) an air source heat pump to kick in when Photo Voltaic (PV) panels are producing more electricity than the house is using, and so at those times top up the water thermal store in the building. This can then be used for hot water or heating (under floor works at lower temps) at other times (if needed).

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 http://zypho.eu/english.html. 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.
–  http://shower-save.com/Joomla_SS/pdfs/Adaptor%20to%2040mm%20for%20RT1-e.pdf
–  http://shower-save.com/pdfs/Recoh-Tray%20grey%20water%20heat%20recovery.pdf

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 http://www.gfxtechnology.com/H-3.pdf

This is also how it’s been set up in the schematic at Bristol (UK) based  http://shower-save.com/
 – also see animation they have at http://content.wavin.com/WAXUK.NSF/pages/Certus-ShowerSave-Animation-EN/$FILE/ShowerSave.swf

UK Water Heat Recovery Supplier Listing:

Test Data for Recoh Units:

From http://shower-save.com/gastec.html

  • 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:

From http://www.gfxtechnology.com/H-3.pdf:

  • 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.

From http://www.renewability.com/power_pipe/index.html:

  • 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 ?

Scarlet Hotel inspiration

Robert from ra-studio and myself went to the the The Scarlet Hotel,  for lunch to go over the plans progress and also to look at several aspects of the Scarlet Hotel that Robert had not seen.

As ever, a stunning lunch with amazing service and some more ideas / inspiration.

Some of which was reminding myself and showing Robert their smaller bedroom layout.

I also thought that we might consider having a central strip / floor corridor of wood from the entrance area, past and through the living area and kitchen, to the top of the 3 stairs down to the lounge. The current plan is slate or tiles for the entrance and living area (dinning, kitchen etc.) and wood for the lower living area.

I also like their stone work fire breast, but not sure this will work.

And good to see further Cornish wood cladding.

Utility, shower and plant room

The idea is that in addition to a downstairs loo and room for shoes and coats, there will be a room for the washing machine, that also has in it a shower, sink, drying rack, and probably screened off, the “plant”.

The plant elements aren’t foliage etc. but the large bits of machinery for the house such as the hot water tank, Mechanical Ventilation with Heat Recovery (MVHR) unit etc.

So, not a lot more on this at the moment, but spotted this photo, that could be a start of this room. ie put the washing machine in a cupboard ?

Waikiki Chic contemporary bathroom

Components:

  • Washing machine
  • Shower
  • Hot water tank
  • MVHR unit
  • Sink
  • Drying area – potentially with a drip tray, as it will probably include wetsuits etc.

It’d make sense to look over the photos etc. for the coats, shoes etc. room.

Not a fan of this look and feel, but the storage looks good for the utility plant room.

traditional-laundry-room

The idea below of an over the washing machines hanging rail could work well. But there also needs to be some full height hanging for wetsuits to dry.

over the washing machines hanging rail

hand rail could be elsewhere:

hanging rail

Washer and dryer platforms. The laundry room below puts the washer and dryer on a pedestal. I’m not having a drying machine, but it might be good to put the washing machine on a slight pedestal.

washing machine raised

Utility room sink to rinse wetsuits etc.

Also some counter top space.

The plant utility room might have extra space for the recycling (there will be some in the kitchen units).

IMG_1335

Coats, shoes etc. room

The first post about this, was creating an area for coats, shoes etc.

I’ve put feedback on these ideas at the bottom of this post >>

The plans are evolving this to a room for coats, shoes etc.

It looks like this is called a Mudroom in the US.

Have a think of what else to add into this room:

  • A safe, as it’s where you might want to leave car keys, wallets etc ?
    • There could be an additional safe for passports, jewellery etc. elsewhere in the house.
  • Black board or other family notice board.
French Country - custom built mud room traditional entry

I like the cushion / lip, so that those who want to, can site down to put on shoes, boots etc.

kitchen eclectic kitchen

I like the lower shoes area is straight onto the floor and not a drawer. This should make it easier to clean /tidy.

 

cubbies and desk traditional hall
traditional hall design by
It’d be good to have a coats, shoes etc. area for the office.
 

Carpenter Gothic Mudroom traditional entry

Having multiple slots, means you can hang coats on the back and side walls of each “slot”. There could be a per person slot (well it could start like that).

ASID Showcase House traditional entry

Or everybody uses one shared space ?

Tudor Addition Mudroom traditional entry
2011 Showcase - Hillside Retreat modern hall

Does this one nail it. Thin walls to segment the spaces and give extra hanging hooks on the separators?

Mudroom Ideas: Locker Room

Baskets for up above, so it’s easy to pull down your basket of stuff. eg wool hats and beanie’s.

mudroom storage traditional entry

Get in multi tiers for shoes. But make sure there is also space for taller boots, wellies etc. too.

 

Farmhouse Revival traditional entry

Getting lots of shoe storage here.

Chez Larsson- Shoe cubbies

and here.

 

better flow - the mudroom / laundry room eclectic laundry room

May as well build storage right to the ceiling !

Mudroom  hall

Feedback on these ideas:

  • There is a danger of the ‘compartments’ being too school like. I prefer maybe 2 large ones, rather than lots of individual ones.
  • Yes to the wood panelling.
  • Should defo go up to the celing with top level shelf/ baskets
  • Keep it simple- maybe half of shoe space double height for wellies & other half 2 shelves
  • Like the sitting bench.

Utility room

  • In my view should also have hanging space for your washing- perhaps like our laundry at home, we have a hanging thing above the washing machines etc .

Mirrors to catch the view.

OK, there are plans for bathroom mirrors, but how about mirrors to reflect the view ?

For example 1 or more mirrors on the south side of the living area or bedrooms that have a northward view over the sea and beach, so that when you look away from the sea, you get these reflected views of the sea.

In the living area, this could be a mirror on the corner post opposite the stairs +/or on the sliding door to the boot room.

from lounge towards the entrance - mirror

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

Portloe house visit

Today, Robert from ra-studio, took to visit a house in Portloe that he worked on before he set up his own practice.

Rob, post visit dropped this in an email to me:

I hope you found the trip over to Claire’s place useful yesterday – it’s sometimes good to experience spaces in a more physical sense / situation, and perhaps helps you to visualise how some of your spaces could feel. I think there are obvious parallels between Sea House and Silver Spray (connection / views / relationship with the sea), and seeing how it has been handled there, I hope was helpful for you.

Yes, well worth the visit. It was fantastic to meet such an obviously happy client (and her cool, crazy young dog, Zola).

Their project was serialised in the Telegraph:

So many things about the house, that I hope to include in Silver Spray. The feeling of space, the flow through the house, the views, the natural materials ……

The house looks over the village and was designed to fit into the slope. Without the red circle, it’d be a chunk less obvious !

You drive up the drive and see the studio on your left with the house a bit beyond.

The cladding on the studio is the same as on the house, but it hasn’t yet worn to the same more grey colour / tint.

The house has an amazing central “spine” so that as you walk up to the front door, you see through to the view.

Although the stone detail of the wall below the cladding looks stunning on this house, it’s not something I feel will work for Silver Spray. Except !!!!! maybe for the rear wall of the courtyard. Well something needs to go on that wall. Perhaps it’ll be a retaining wall held back by Gabions (steel cages of rocks). But a quick on-line search suggests the life of Gabions, which is down to the life of the steel holding them together is 50 to 60 years. I suspect less in Silver Spray site, so close to the sea. Damn, as they’d be great.

The slate flooring runs from around much of the house, straight into the house, where it’s apparently super easy to clean. The texture it gives was fantastic. The same slate was used for the external window sills.

Almost all of the windows are by Velfac, with thin profiles, nice colours etc.

This upstairs window has a piece of glass over the front to create a “Juliet Balcony”. Which will work great for the second bedroom.

I’m still not a fan of the idea of wooden decking. Here there was a mixture of slate and wooden decking.

Coat room to the left as you walk in 🙂

Lovely doors, floor and wooden stairs:

Nice detailing on this sliding door that can close over the entrance to the kitchen.

Wide, light floor boards. Interestingly, wooden floors upstairs. I was thinking carpet, but this did work well. OK they have light coloured tiles in the bathrooms upstairs. The bedrooms had good integrated storage.

The above white TV makes it less dominant on the room. Also a superb idea that it pushes against the wall, but is on an arm that can come out and so be viewed from the seating etc. This could be a great idea for in any bedrooms. Although I’m not planning TVs in the bedrooms, it’d be good to allow this future option.
Having a TV in the 2nd bedroom for guests could be a nice touch.

Pebbles in a gulley outside the door, to prevent splash up from rain onto the windows and also to drain away water flowing down the windows.

A photo from when the studio was being built:

The house has solar heating and solar electricity.

Light and ventilation tunnel ?

With the stairs going from the floor of the house, to the top and being capped by a sky-light, and also a south facing window (or two) at the top of this “column”, I was reminded of the Potton Lighthouse, with it’s “wind catcher / light funnel”.

I’m wondering if these windows could be an automatic, intrinsic way that the house heats and cools itself down?

Below is a screen shot from a PDF about the Potton Lighthouse.

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