Eco House Thailand

This blog tells the story of how I am building an off grid home in Thailand. There is a section that explains my initial Design Ideas  and sections on how I manage Water and grow food.

The site is on the edge of the family’s village was a field of teak trees. It is 1 Rai (1,600 m2) and cost ฿650,000. The price is a bit high, but it is perfect location for us, as it faces onto a road and has an electricity pole 10m away. Cutting the Chanote (land title)  to give us 1 Rai cost  ฿20,000 + ฿10,000 for an express service. I have a 30 year lease on the land and my name is on the title papers.

The Land where we planned to build was raised up by 1.5m with heavy clay soil to avoid flooding and cost ฿380 per truck with 150 trucks cost ฿57,000. The soil was left for a year to sit through a rainy season to compact.

No power on site, so a trip to PEA (Provincial Electricity Authority) is required to set up a temporary meter.

At PEA identifying the closest electrical post to our land, which in our case is about 5m away. Each post has a unique number on the post and in the PEA system – quite impressed. ฿6,000 deposit paid for the temporary meter.

Our builder Khun Own, had to climb the post to make the connection, all PEA had to do was fit the temporary meter.

Power connected!

Fitting geothermal. 30minutes with the digger gave me a 3m deep trench which cost me ฿750. 100m of pipe cost ฿3,600.

Below 2m the ground is much cooler than at the surface. Air will travel for 100m in this cool soil before it is introduced into the Energy Recovery Ventilator in the house. My Thai neighbors don’t know what to make of it or the fact that most of my windows are sealed shut.

Main Build:
I couldn’t find a Thai architect who shared my vision. Before I met each one, I sent them a copy of my detailed design ideas, which they did not look at.  In the end I employed an engineer who took my designs and put them into a form that was acceptable to the Government Office that approves home builds, cost ฿20,000, with ฿1,000 for government approval to build.

Testing how deep the foundations need to go, 6m in our case. I thought ฿5,000 was a bit expensive by Thai standards, but it came with a full engineers report and recommendation for the foundation type and size of steel to use.

My house is just sticks in the ground

6m deep holes

Filled with steel and concrete

House now looks like a battlefield

Dig some more holes

Add some more concrete

Add more steel, a lucky stick, some coins and a leaf

More steel for the column

More concrete

Stage payment to complete all the foundations and column steel ฿300,000

Adding formwork and steel for ground floor walls

Geothermal pipe gets insulated coat where it comes out of the ground to enter the house

Sand added between the beams to give a good flat surface to lay the concrete floors on. Sand also reduces the thermal bridge effect, meaning that less cooling is wicked into the ground below, the opposite to what happens in northern countries.

The sand is part filled, wetted, compacted and the process is repeated. I paid an extra ฿10,000 for the sand, instead of the usual Thai method of using whatever dirt is on site.

Ordered some insulation foam 184m2 = ฿20,900Delivered by overnight truck from Bangkok ฿6,500.  Foam will be used for underfloor insulation on the ground, second floor and third floor.

30cm of compacted sand, then a vapor barrier and then 3 inches of foam.

 If you don’t have a Hot Wire Foam & Polystyrene Cutter, then use a bread knife

The Foam floor was a big hit with the village kids…”Dances with Thai Dog”?

Adding more steel, ready for more concrete

Concrete for the columns

As the columns for the wrap around porch are filled with concrete, the columns for the second floor are wrapped in plastic cling film. To prevent cracking, plastic is placed over the curing concrete to trap the water inside, ensuring gradual curing.

Second stage payment ฿267,500 for completion of ground floor slab; initial plumbing, waste water, and columns.

Ring beam for the second floor. The smaller posts are to support the wrap around roof on the ground floor.

Bought some windows for the “wet rooms” – kitchen and bathrooms. These windows will be constantly open. They incorporate stainless steel security bars and mosquito screens.  80cm x 50cm are ฿2,690

The larger ones for the kitchen are 240cm x 110cm @ ฿8,690. With Thai cooking it is important to get plenty of fresh air into the kitchen. The usual approach to windows is to build the house and have the windows made to measure to fit. For the non-conditioned “wet rooms” I am buying the windows cheaply off the shelf first and then building the walls to fit.

The second floor concrete floor arrives. The little house of straw and plastic sheeting is where the night security team sleep during the build.

Great view from the second floor, can’t wait to see the view from the third floor!

More foam added to the second floor and then more steel. I plan to have a home cinema on the second floor and the foam will help to dampen the noise.

More concrete and we have a second floor.

Concrete columns up to the third floor

The name for this in Thai is “Slider”  The cost of building concrete staircases from the ground to the second floor and from the second to the third is ฿40,000. The third stage payment is ฿267,000.

Ring beam for the third floor. The front and back of the house will have 8m wide by 1m deep balconies on the third floor, which will help with shading.

The last couple of days I have been distracted from the house build by another project.

On a recent visit to my local Primary school, I noticed the students watering a dry patch of dirt. I was told that they were trying to grow some vegetables.

I saw that there was a pond nearby, so asked why they didn’t pump the water onto the land. (stupid question) – no money for pump and no money for electricity even if they had a pump. So I set about a little project that would help the school and hopefully be educational.  I purchased a 320 watt solar panel; Pump; DC motor and control box.

First requirement was a frame to hold the solar panel at 15 degrees.

Then sort out the electrics for the motor and pump.

Note my use of zip ties to hold it all together.

Back to the build: a boom concrete pump which uses a remote-controlled articulating robotic arm to place concrete accurately in the ring beam for the third floor. The concrete is poured from the concrete truck into a second truck which pumps it up to the third floor.

There was a little concrete left over and I have another parking place.

The first Q-CON blocks have arrived. They are Autoclaved Aerated Concrete Blocks (AAC Blocks). AAC is light and the blocks are joined with a thin bed of mortar. They offers excellent sound and thermal insulation, are strong and fire resistant. Originally I was going to use 20cm wide blocks, but have decided to use 2×7.5cm blocks between which I will put 7cm of foam with a silver radiant barrier that reflects thermal radiation and further reduces heat transfer.

I have agreed a price with my builder to purchase and fit all the Q-Con blocks for the three floors, including any steel/concrete reinforcement, the SCG block “glue” and render. This includes the double block walls in the main block and the single block walls for the kitchen, bathrooms and porch. I will purchase and fit any foam/foil insulation. The price includes fitting all the windows and doors (which I will buy) ฿500,000

The blocks are easy to cut and work with, so the walls go up fast.

Two guys put these walls up in a couple of hours. Steel bars are inserted between the rows and joined into the columns. Additional concrete and steel columns are added every couple of meters for extra strength.

Crane arrived to fly the floor planks up to the third floor.

Cracking view from the top

Another giant crane arrived today to deliver concrete to the third floor.

Walls progressing and columns built for the roof. The fourth stage payment is ฿267,000

To avoid any confusion on where the doors go  – latest plan attached to the wall for all to see. The main block can only be accessed via the porch or the kitchen so there are 2 sets of doors.

The same three inches of foam that we used under all the floors will be sandwiched between two 7.5cm Q-CON blocks in the walls of the main block. The double sided foil insulation is stapled to the inside of the outside wall  – ฿1,900 for 75m2

To fill the gaps we used expanding polyurethane foam, just one more product that the builders had not seen before.

Then a second wall of Q-Con Blocks

Starting the staircase to the third floor. As we are not planning to be dragging any sofas up these stairs, they are designed to be quite steep and narrow to save space. If we do decide to have a ping pong table or the like on the third floor, we can always pull it up the side of the building.

Measuring for the roof. I have decided to use Bluescope Colorbond steel roof for the build. An expensive steel roof by Thai standards. Colorbond uses Zincalume® steel, a Zinc-Aluminium Alloy and the colour is then baked on to the surface, hence the name “colorbond”. It comes with a 30 year anti rust warranty. I have chosen .44mm thickness in white. I have also ordered 5mm of foiled coated foam to be preattached to the steel at the factory. This improves the thermal reflection of the roof and reduces the noise from rain. The materials cost for the roof  above the third floor is ฿48,000 but this cost is included in the quotation I received from my builder.o he will be paying.

The roof and walls of the house have reflective foil insulation, able to stop more than 97-percent of radiant heat. There is also a layer of foam in the roof,  walls and floors to reduce Thermal Conductivity.

The roof sections arrive. Attached to each sheet is 5mm of foam and silver radiant barrier. The sections are the whole length of the roof, so there will be no joins. They overlap each other with the ridge section on the right with no foam sitting on top of the ridge section of the next piece.

The galvanized screws, complete with rubber washer are colour matched to the roof – in my case white.

The first job is to pull all the roof sections up onto the roof.

Galvanized wire mesh is then attached to the roof steel, this prevents the foam from falling off the roof panels.

There have been some comments from the locals about why The House has no windows. In the thermal envelope of a building, the weakest link are the window frames – so I don’t have any. The next area of weakness are the windows themselves. In Thailand, double glazed windows are not easily available and are very expensive.

The glass in a clear glass block is much thicker than standard window glass and there is a much wider air gap between the panes than what you would find in double glazing. The result is a window that is far better insulated and soundproofed and only costs ฿48 per block.

As steel bars will be inserted between the blocks and tied into the walls, they are much stronger and more secure than standard windows. When the double internal walls are finished, the glass block windows will be added.

Ventilation will come from in the form of filtered, cooled, dried air which will be pumped into each room from the ground source geothermal and the Energy Recovery Ventilator.

The reduced view from the small windows will be supplemented by “virtual windows” from security camera feeds.

It is far cooler on the third floor than at ground level, this is partly due to the fact that wind speeds are higher with increased height, but the speed of the wind is further increased by the building design. The wind is funneled by the sloping roof and partial side walls, this  phenomenon is called The Venturi Effect

Doors:

Internal doors will not be made of wood, which rots quickly in the hot humid tropics and is also subject to termite attack. So I have chosen foam filled UPVC from eco-door at ฿3,200 including frame.  External doors will be oversized and made to measure in high grade stainless steel ranging in price from ฿12,000 to ฿16,000 depending on size. The doors are currently being manufactured and I will post pictures when they arrive. Three ground floor stainless doors will be equipped with biometric digital door locks from eco-door at ฿5,500 each

There will also be a stainless steel door at the top of the second floor to secure the whole floor as a safe-room. The third floor will have a stainless door to prevent access down to the second floor or up from the second floor, making the third floor a place of “last stand” there being a rope ladder on the third floor down to the ground.

Stainless steel doors will all be fitted with stainless steel Zombie-Bar security barricades made by the door company. Basically a piece of medieval technology, but it is time tested.

The  blockwork for the porch on the left and kitchen and bathrooms on the right has started to go up. These rooms are part of the buffer zone and will not be air-conditioned. My plan is to have all the “wet-rooms” (kitchen and bathrooms) together. It simplifies the plumbing of the solar thermal hot water and means no chance of a leaking pipe in the main house. You can see that window holes for these rooms has started to be punched out. These rooms will be naturally ventilated, so will have the only windows that actually open.

Before applying the render a primer coat is sprayed onto the brickwork.

The stairs from ground to second floor and from second floor to third are boxed in to prevent air-con being wasted into areas not being used. It also means that a security door can be placed at the top of the stairs.

One thing that many people comment upon when they see the house is the thickness of the walls compared to the bricks used in most Thai house construction.

For symmetrical reasons the front of the house will have the same glass block windows for the ground and second floor. However, three of windows on the second floor will be for the home cinema, where having windows would cause a problem, so an opening is cut only through the first wall as far as the foil and the glass blocks used will be patterned and not be clear.

Rendering has started and they are doing a good job of itThe rendering is a major part of the build and will take some time to complete.

New transformer being added on the road into our village, bit of luck for me as mine is the first house in the village and closest to the transformer.

I thought I was long finished with digging holes, but these three holes are for 3 more posts to go in front of the house in line with the 2 existing posts. These new posts will mean I will be able to run the Blue Scope steel roof across the front of the property and join up with roofs of the carport and bathrooms. If you want to read the story of why this was not done from the beginning and you are not afraid of Ghosts then visit: https://ecohousethailand.wordpress.com/building-the-thai-way/

These three posts gives me a new 20m2 room in front of the bathrooms which will act as a pump room/invertor room/battery storage. I will also gain 40m2 of roof area facing due south for solar panels as well as a much extended carport.

The outside render is complete

Tomorrow have a busy day helping the top builder fit the electrics. I have prepared an electrical plan, but it will need some explaining. Labour to fit the electrics ฿40,000.

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Still need to paint the walls, so not all the trunking is going in yet. Copper speaker cable marks the spot for a wall speaker

Thais prefer to use individual wires as they can get away with thinner (cheaper) trunking.  I want all the colours to match in the house, so insisted on sheathed wiring. Also using Twist Connectors rather than just tape. It helps if you insist on paying for all components yourself as this rules out cost as a determining factor.

Your ability to successfully terminate LAN cable is a factor of the quality of your connectors and your eye sight. In my case, fail on both counts.

Luckily I had more success terminating using Cat6 Keystone Jacks

Cables going down to the second floor: Lights; Power Sockets; Led Strips; Speakers; Security Cameras; WiFi and 3G/4G Booster.

Outside of the building is all primed and we are starting on the top coat – Dulux Weathershield Ultima in Bright Shiny White.A contrasting color had to be chosen for columns etc where heat reflection was not critical. Sophisticated Grey was chosen and I had great fun asking the Thai Staff what the colour was called. The colour is mixed by computer, so we will always be able to match it.

My Energy Recovery Ventilator arrived today, now just have to work out the how to get the ducting installed to feed fresh air to all rooms. The ducting needs to bring fresh air in from my Geothermal system through the ERV, then split to send fresh air to the ground and second floors and stale out   Video explaining ERVs

Even though the ERV has it’s own filter, I will also be installing a wall mounted HEPA air filter in the bedroom

Some decorative concrete is being attached to the building, which will be painted Sophisticated Grey  ฿300 per meter to make and fit

The cabling for 5 Video cameras are being fitted before the ceilings go in. The cameras are connected to the control box by CAT6 ethernet cable with POE (Power Over Ethernet) – so a few less power sockets to fit.

Ceiling on the third floor going in and being painted

Foam applied to the back wall of the home cinema to insulated it from the adjacent room

LEDs starting to go in

Starting to build the Mechanical Room

Waxed Loft Style paint for the interior

Control box for my solar pump – now an ant house – another problem with building in the tropics

Scaffolding comes down and the steel for the wrap around roof on the first floor starts to go in.

Bought a little Christmas tree to put on top of my house – great difficulty was had trying to explain what it was and why I wanted it.

The Mechanical Room is almost complete.  5m x 4m this room will house the invertors and batteries as well as additional electrical components for the solar system. It will also have filters for the whole house water system and a drinking water filter system. One item that will not be in the mechanical room is the Energy Recovery Ventilator. The ERV needs to live within the airconditioned envelope of the house.

Why you need to paint the outside walls of your house white.

Visit to our stainless fabricators. They are making up the first of our stainless security doors. They have taken our biometric door lock to fit for us. The girl with the glasses, speaks excellent English and has made the whole process very easy. In the background is the stainless railings for the third floor.

Stainless Security Door on the third floor with Biometric Lock

New Stainless Railings

Nice neat job on the wiring for one of my three consumer units.

Ducting for the energy recovery ventilator, which brings fresh air to all rooms.

I personally installed approximately 300m of Cat 6 cable for home networking with another 100m or so being installed by the security camera company.

27U Network Server Rack – This is a floor standing cabinet, which probably takes up no more room than the usual 6U wall mounted rack.

Bought some furniture for the third floor from the Cambodian market ฿30,000

Nice place to watch a tropical storm

Visited Piyanas HiFi store in Bangkok to demo some kit for the home cinema

TANNOY REVOLUTION XT-8F  x2 front speakers with TANNOY : REVOLUTION XT-C  x1 center channel. TANNOY : REVOLUTION XT-6F  x4 for side and surround.

You can hear the REVOLUTION XT-8F  here  and a review of them  here

https://www.whathifi.com/tannoy/revolution-xt8f/review

B&W CCM-362 x2 IN-CEILING speakers to support Dolby Atmos

A/V Receiver: ONKYO : TX-RZ730

Total cost ฿163,600

Having listened to the CAMBRIDGE AUDIO :EDGE-NQ  Network Player with Preamplifier and CAMBRIDGE AUDIO : EDGE-W Power Amp they will definitely be my next purchase, but at ฿258,000 it will have to wait until the house is finished.

I did demo a pair of REL Acoustics subs but will wait until I have accessed the cinema room dynamics before purchasing.

An Introduction to the Edge Series Cambridge Audio

We attended the Architect Show in Bangkok

Bought a Sliding gate automation system which we will be installing later

Bought some Mr Ken Fans with DC Motors and got a show discount

The fans are beautiful, very efficient and very quite. As they all have DC motors, they are very efficient.

Lots of smart home kit available:I was even able to pick up a smart controller for my Energy Recovery Ventilator (top)

The stainless steel doors have been installed:

Did a little testing of the home theater today. I did a calibration for the 7 Tannoy speakers and the B&W Dolby Atmos ceiling speakers. I have ordered the screen but not the projector (The prices are falling all the time) so we used a 50 inch 4K TV I was planning to use with security camera feeds.  I am not sure I need subs, the Tannoy 8s have great bass. We have bought some acoustic foam and will be using roomeqwizard.com acoustics analysis software for measuring and analyzing the room and loudspeaker responses, before placement. My girlfriend’s brother who is an engineer came to help, he wanted to know what the sound was like, because he said for the same money, he could buy a Thai mobile disco system that would fill a 6 wheel truck!

Interior doors going in:

And the rest of the windows outside the main block:With extra longs screws into the concrete.

The house must be nearly finished if I am buying ping pong tables!

Air-conditioning:

Aircon serves two purposes, firstly to cool and secondly to dehumidify the house. I briefly considered using DC aircon units, but they require dedicated solar panels and dedicated batteries, they are also very expensive to buy in Thailand. So DC aircon for a spare bedroom would have solar panels and batteries that were not being used if the room was empty. I prefer to pool my solar production and storage to use it where it is needed.

The main concern with running aircon off a solar system is how to run aircon at night off batteries. My system utilizes a hybrid inverter so I can always pull from the grid if I need more power. However, I want to design my house to be off grid for normal use.

The choice of aircon units: I chose the smallest BTU units I could find using the smallest number of watts. I chose 8,500 BTU Daikin Super Smile Inverter II it uses 640w in normally running and an “intelligent eye” system which tracks movement and reduces power if the room is unoccupied. 5 units installed was ฿100,000

Aircon installation in a thunderstorm.

The next question that will come up is why fit the compressors at the front of the house and not at the back? The front of the house is where the vehicles will be parked, it is the south facing aspect of the house, while the back of the house is the north side and we will be eating on the back patio. I do not want it heated up by the compressors blowing. For my design Form Follows Function.

I have tried to use dropped ceilings wherever possible to give me the option to use concealed lighting. With LED strips, the colour can be changed to match your mood.

The ensuite bathroom is outside the conditioned space, so there is little cooling costs apart from a fan and auto extractor fan.

Hot water is free, so a bath is not a luxury and the waste water is recycled to water the garden.

Built-in black acrylic bedroom furniture by Ice Furniture in Buriram :

First night staying in the house:

Solar Thermal hot water system worked great:

View back to the house from the pond at dusk:

The rainwater overflow combined with the rains we have had this month have done a lot to fill the pond

Starting to work on the networking:

All the network cables end up on the second floor outside the Home Theater. The cables are all labeled at both ends and bundled by room.

The first job was to tidy up the cables and then them punch through to the home cinema. Then set up the 3G Booster. Due to the fact that I have silver foil in the walls and the roof, the building is basically a Faraday Cage , which is great if you are worried about an EMP (electromagnetic pulse) but not so great if you are trying to get a 3G signal from inside the house. So I have an antenna on on third third floor pointing at the cell tower:

linked to a booster box and 3G aerials on the second and ground floors:

The next job is to terminate the network cables into a patch panel in my network cabinet:

First job is the label the cables going into the patch panel and the corresponding keystone jacks for the wall sockets

Then strip the cable and punch it down into the patch panel

Then repeat at the other end in the wall plate keystone jack then test the connection

Network points – the other end from the patch panel, installed in rooms.

Long range WiFi access point installed on the third floor to give WiFi out to the pond and to the family house several hundred meters away. Also installed, a pair of Yamaha waterproof speakers.

They are linked to an amp in the Networks Cabinet and a Sonos Connect Network Music player, which allows music to be accessed from the network and controlled from an app on your phone.

I also have a Sonos One smart speaker in the kitchen which can also play music from my network or from my Tidal HiFi streaming subscription:

“Fishing Fiber” running fiber-optic cable from the network cabinet on the second floor out to the street, so that my Internet Service Provider can easily connect to my network.

Cables are run in conduits in the ceilings and underground, all with prepared pull through lines. Life is easier if you plan ahead.

Another thing that you normally only see in commercial buildings are inspection hatches to give access to wiring in the ceilings. Practical always wins over pretty in this house.

1 Gigabit/Second Fiber broadband connected and all 4 Ubiquiti WiFi access points showing blue LEDs that they are connected.

Kitchen, not completely finished at this stage. The cabinets have the same black acrylic as in the bedroom with green Indian marble worktops and brushed stainless fittings, sinks and cook-tops:

The island is recessed to accommodate seating.

The gas tanks are outside and have valve gauges to take the guesswork out of determining how full they are.

Solar Installation:

The system is Off Grid Hybrid

Solar panels are Monocrystalline 350W X32 = 11.2kW
Deep Cycle Gel Batteries 12V 200AH X 16 = 38.4kWH
(A Tesla Powerwall 2 has a capacity of 13.5 kilowatt-hours)

Clamps and brackets:

Video: All the panels mounted

32 x 350 watt = 11.2kw for home electrics and 2 x 320 for solar well pump

Inverter and Battery Bank. 10kW Hybrid Inverter and 16 Deep Cycle Gel Batteries 12V 200AH  = 38.4kWH

Having panels on all sides of the house we are producing power whenever the sun shines

6am and already producing more power than we are consuming

But by midday all panels are in full sun producing 11kw

Security cameras installed:

Camera display in the office and also available on the living-room TV as a virtual window:

There is a mobile app to view the camera feeds when away from the house.

Infrared for night time security:

An update on the Energy Recovery Ventilator, before all all the ducting is boxed in.

The more you insulate, the more you need to ventilate.

The inter core of my building is a conditioned space, with windows that are sealed shut and doors with 4 frames and airtight seals around the top, bottom and sides.

So it is important to bring fresh air in and take stale air out. The fresh air is cooled by outgoing air-conditioned air, then filtered. Incoming humid air passes humidity to the dry expelled air.

The ERV will cool incoming air, filter it and reduce its moisture content.

Air exhaust and intake

Controller set to heat exchange.

There is still some concern that with such a tightly sealed house, C02 levels could build up

So we monitor CO2 levels

As well as atmospheric particulate matter at 2.5 micrometers

and 10 micrometers

In addition we have a HEPA air purifier running in the bedroom

TV for the living-room being delivered.

TV setup in the living-room. LG 86 inch TV with with Denon AV amp; Castle Knight 4 left and right channel speakers and Klipsch R-34C center channel.

A 50 inch tv takes on the role of virtual window

The old 55 inch TV was moved into the Bedroom

Bedroom TV with Harman Kardon Aura Studio 2 speaker. There is a Xiaomi MI BOX S 4K Ultra android tv box in both the living-room and the bedroom. The living-room also has an Apple TV box.

We use the TV boxes to access Netflix, YouTube and stream content from my PLEX media server.

The PLEX media server is installed on my Synology Network-attached storage (NAS), which has 8 bays for drives into which I have installed 8 × 10.0 TB HDD SEAGATE IRONWOLF  drives.

Starting to get the food pantry organised – lots more space in the kitchen to fill

The fitness room on the second floor has taken a step forward with the purchase of a BOWFLEX MAX TRAINER M3  which is a cross between an elliptical trainer and a StairMaster – a very good cardio workout

We upgraded security when we rescued a black Labrador called Rambo.

He is about twice the size of any dogs in the village and he seems to terrify the locals.

Walking him twice a day with our Thai dog Panda is helping with cardio.

Another security device we have installed is a steel locked key box.

The box prevents the keys from being cloned:

or fished:

Any zombies that make it into the house will be in for a big surprise.

Latest project: Installing solar lights. In total we installed 6 lights around the property. @฿1,800 each they are far more expensive than some models I have seen online, but they have a large solar panel and the light lasts all night. There use saves running lights off the house batteries at night and they give enough light to greatly improve the quality of the security camera footage.

We have decided to replace our 160L upright freezer (purchased while I was living in a condo) with a 429L chest freezer. The freezer will run on a timer from 9am to 5pm (so powered only by solar and not running down the batteries)  It will not be opened outside these times and it will be well stacked with ice to give it a good cold sink. Our fridge has a small freezer.

If you are interested in the efficiency of chest freezers, see the video below

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