Martins pool- and workshop project.

Deadline June 2024.

Discussions held during 2021 about the project.
The average downpour of rain in Tønsberg is 492 mm April to October included.
April 56 Spør en energirådgiver! (

Here we can assume that the relative humidity (RF) is 40%, that the air velocity above the pool is 0.15 m/s (~wind-quiet) and the average for the air temperature over the day.
Furthermore, we can assume that the pool temperature gradually becomes the same as the average air temperature over the course of the day
("The inertia" of the heat balance of the water provides for this),
and here we try our way with the average temperature of 26 degrees C.
From the table work, we then find that it should evaporate 191 grams per hour from each square meter of quiet water surface. (RF 40%).

Then it is 0.191 kg * 24 hours * 50 m2 does not provide more than 220 liters of evaporated water per day or 1540 liters per week.
Something more than U.S. figures show.


Mai 64
June 68
July 86
August 115
September 103
October 125


There are 3 westward surfaces on the house that can be used for water collection.
Total of 3x4,5 M2 + 7,5x6,5 M2 + 6,1x3,8 M2 = 85 M2 or 8500 DM2.

If a total of 60% for the rain water can be collected, we will have 8500*4,92 liters
of water or 41 800 liters.
60% of this is roughly 25 000 liters from April to October, included.

How much will evaporate from the pool? 2 - 25 mm in a week. Let say 12 mm.

Area 50 M2 gives a loss of 5000*0,12 = 600 liters a week. That works out to 600*49 = 29 000 liters.
Roughly what we get in rainwater in the same period.

My calculator on the net gives 650, not a much difference.



Border to the East.

Border to the North.

This is the pump room and where to put what is the next problem. Since the pool will not have a skimmer since the water flows over the edge on the South and West side, and into the gutter. Then we need a filter mechanism to take out all the leaves and heavy debris before it gets into the system and the backup water storage. Where should we put it? On the North and South edge or only one of them.

Here are the the system. Where to put what?
North End solution:
That means that we will have a filter tank that takes all the shit out the water before it goes into the rain water backup tanks of some 3-5000 liters. That will be at point 2) on the sketch. Here we will have both tanks before the valve.

All rainwater will be led into this tank. It will have an automatic release valve if too full and the water will go into the drainage ditch as the backwash water will. This is a gravity tank and when the system work, water will be pumped from this tank.

Where to put the wood fired oven with a water jacket? At  point 10) or point 15). It will be in the same room as the wood fired sauna oven.


Putting out heat isolation.

Hvordan varmevekslingen foregår. Les mer i manualen.

Basseng med plexiglass for å forhindre vannsprut. Overløpsrenne kommer klart fram

Det er 30 cm høyt og 1 cm tykt og løpr langs den ene sida.

Vi vil ha det mot nord og øst hvor det ikke skal være noe overløpsrenne.

Skisse som viser hvordan nybygget er plassert på tomta i forhold til tomtegrenser. Det er 950 cm til fylkesveiens grense.

Skisse som viser hvordan bassenget og verksted er i forhold til huset.

Tverrsnitt av nybygg som viser hvor lang ned det skal graves. Her er det 235 cm, men det er i drøyeste laget. Dette vil bli redusert til 200 cm slik at området rundt bassenget vil være 35 cm over vannkanten.

Hvordan en varmepumpe virker sammen med bassengsirkulasjonen. Les mer her.  


Varmepumpehus med tank.

Liten vedfyrt badstueovn til 6000 NOK. Ovn med vannkappe vil ikke kunne varme opp ei badstue.

Varmepumpe for basseng, 16KW.
 Heating calculation 
 18000 kcal / kg wood. Effeciency 80% 
 Heat up 1 liter of water 1 degree need 1kcal 
 Pool is 50 000 liters or 50 M3 = 50 000 liters 
 Your own is 7KWH = 7*860 kcalories = 6000 kcal 
To heat up 50 000 liters 1 degree 
 you need 50/(18*,8) kg wood. = 3,5 kg of wood 
 Your own need  50 000 / 6000 = 8,4 hours 
 Heat pump delivers 16KWH =  
860*16 = 13800 kcal
Letting the pump work for 5 hours a night will
heat the pool by (138000*5)/50 000 = 140C


Denne vedovnen med vannkappe er et alternativt. Effect cirka 7KW.




Here is the latest update. I have a few point to discuss.

1. Drainage from the pool.
2. Drainage from the grill area.
3. Drainage from the container.
4. From the North side.
        At FP2 to the pool and
        At FP1 to the workshop.
5. From the South side.

The workshop is 220 high. The work area is only 220-70 = 150 high. Is that feasible?

New entrance to the basement and pool. Next to the entrance door, there will be a shed for the firewood to heat the pool.   The garage is 180 cm out from house wall.

The door well to the basement will be extended to the end of the pool. Staircase width is 90 cm.

Where the pool will be in the garden.

This will be covered and the rain water will be led down into the pool which has an overflow tank.

This is a way to keep the water warm. But it should not be sealed at one end so the pool can be used even with the roof on. You should be able to swim inder the cover.

Standard ISO shipping containers are 8ft (2.43m) wide, 8.5ft (2.59m) high and come in two lengths; 20ft (6.06m) and 40ft (12.2m).

The horizontal stairs are 207 meters long. Good to remember.

Here you have MUR-031 rev A, RIN-051 and Technical Manual, Chapter 7 for details.

Dimensions of different Leca blocks.

This shows preliminary starting points of stairs, pool and container.

The measurement of the pool in relation to the house.

Base sketch.

The first sketch to wrong scale. It should be 1:50 but is 1:100. And some lengths are missing.

Basement figures.

First full-scale sketch of the location of store room and pump room.

How big is JAP's kitchen?

The sketch from Aug 29th, 2021.  

Regarding the mass from digging. It can be used for leveling the garden toward road direction because is falling that way.

I do not think the container for workshop can be buried all so deep. I think can be used to extend your terrace .

I can mark the pool some day, today I am away on sea. I was thinking to borrow a laser level at work and measure also the levels.

How to deposit the mass from digging?

If the container is sticking up 100 cm above the pool, we don't have to dig so  much.

Your idea of having the container a meter above the ground is a good one. See my comments on the issue.

Move the pool and container further South.

Flag Points coordinates per 12th September:

He means you will have to continuously feed the fire with wood. Just standing beside and adding wood all time to get the effect.



What I mean by mass balance is that both the pool and container will be above the ground 30-50 cm and the mass used to level it out.

The deepest we can dig is the no of cms JAP's floor is under the ground.
Otherwise, the idea with and extended patio at the end of the pool = container roof?

I conclude as you that the top of the container will be a patio next to the pool some 50 cm over present day ground level. May be higher. To extend the shooting workshop, I add 2 meters and use the doors as roof of that part. The doors are 240x220 cm.

August 2021:
I want to dig out an area in front of the kitchen some 450x470cm big room for a tank some 3-5000 liters for rainwater and backup for the pool. some 21 m2 big.
Se latest drawing.

The mass from the digging, I will deposit around the garden. The pool will be at the same level as the veranda, some 30cm up. You can measure that too.

September 2021:
You really gave me some good ideas. Now, the pool wall starts 1 meter from the garage, 330 from the house wall and 6 meters from the bedroom wall.

Then the digging shouldn't interfere with anything of the house. Also, if the lawn is 60 cm below the veranda, the depth of the digging should be only 1 meter for the pool and some 150 cm for the container area.

The container is 260 cm high. Then it will stick up only 60 cm above the pool. If we only dig 100 cm, it will stick up 100 cm above the pool, which may be a good idea. Or dig 120 and it is half a meter above the pool Your take on this?

We rather dig the container 190 cm below the veranda. Then 30 cm sticks up above the pool. Good idea? So the area can be used for a sunbath/sitting.

The pool patio close to the pool is 1550x200 = 31 m2, and the container area is 1800x250+250*200 = 50 m2 and is 30 cm above the pool patio.

Oppvarming blir en 16 KW's varmepumpe og en vedovn med vannkappe. Se nedenfor.

I was thinking about the container. Should be keep it level with the pool. Then we get a big free area approx. 15 x4 meters for pool space.

 It means digging down some 120 cm. Assuming the ground is 100 cm lower at FP1, 5 & 6. Then we have a hole at the same depth and is easy to excavate.

Another lovely workout, swim and saunas with beers.
I got the idea that we can make a sauna oven from Lecablocks and the remains of the oven that you gave me. But I am not sure if we can do that due to cleanburning shit etc. After all this is an outdoor fireplace.
A big oven 50x50 cm that works as a sauna oven. Then I have been thinking of being able to route all the electricity from heating the pool to the sauna when in use.
What do you think?

Then if I can, I put a coil inside the oven to heat water, for fun.
Do you think this will take bare flames?
I get ideas when drunk, happy and in a sauna. Life is good.
8:09 PM
An very nice, expensive dinner out with super food, lovely beers and Jägermeister. Great end of a day.

Can't you make an oven with a water coat just of cast iron pipes?
Outside diameter for the burning chamber i 30 cm, and the outside 50?
Then you get a layer of 8-9 cm around the burning chamber.
I saw something like this on the net.
Have it 150 cm long at an angle. Easy to clean and very effective.
Then we have no heating problems for the oven.

How to make heater? Read here!

How should we make the container:

  1. Flush with the veranda  means digging some 2 meters down.

  2. 30 cm above the veranda  means digging some 170 cm down

  3. Or 60 cm above above the veranda  means digging some 140 cm down?

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Any comments?

Last updated on July 15, 2021 at 04:32 hours.