Copper tube underfloor heating in Bathroom.

[motorhomes4sale]

Fantastic! When I felt a warm patch from pipes under our bathroom floor I realised I could easily have done the same thing but by then it was too late, it was all screwed down and covered.

Don't tell my wife.

Thanks.

It was my friends bathroom floor that gave me the idea. He said his bathroom floor was quite warm in places because there were some pipes running near to the floor boards. I didn't have a lot to loose in trying what ive done. For me it was a no brainer, there was no way it couldn't work.

 

[swigger909]

Well I think it's brilliant!
I was looking at doing something similar using pex in our new kitchen diner. If all it costs me is the pipe, I've nothing to lose.
B

 

[motorhomes4sale]

Well I think it's brilliant!
I was looking at doing something similar using pex in our new kitchen diner. If all it costs me is the pipe, I've nothing to lose.
B

I am not sure how much heat you will get out of 15mm plastic pipe as I think that has been designed to keep the heat in. The underfloor heating plastic pipe is a thinner wall pipe and is 16mm outside diameter, this would be a problem to join into the flow and return on central heating system. Normally underfloor heating would be run from manifolds which are piped to the boiler, the 16mm pipe joins into the manifold. I only wanted to heat about 1.5 sqm of floor so extending the flow and return to the bathroom radiator was the easiest option, and it works great.

If you want to try 15mm plastic pipe do an experiment. Get the amount of pipe you would need, lay it out on top of the kitchen floor and join it in to a flow and return on your system and see if it gets hot. If it does which I am not sure it will get any where near as hot as copper then you are half way there. If you are going to put it under a wooden floor like me then make sure you insulate as much as you can below it with that reflective aluminimum stuff and the 200mm stuff you use in a loft, other wise the heat would be wasted trying to heat the space below the pipes.

Edit: I have just found on Ebay that you can buy 16mm to 15mm compression fittings so you could do under your kitchen floor with the proper 16mm UFH pipe.

http://cgi.ebay.co.uk/ws/eBayISAPI....akeTrack=true&ssPageName=VIP:watchlink:top:en

 

[Agile]

Plastic CH pipe is only designed to keep the water in and oxygen out. Heat transfer is not part of the design. It should also be insulated just like copper.

It will make little difference to the heat output to use it for the underfloor.

Tony

 

[motorhomes4sale]

Plastic CH pipe is only designed to keep the water in and oxygen out. Heat transfer is not part of the design. It should also be insulated just like copper.

It will make little difference to the heat output to use it for the underfloor.

Tony

I did not experiment with plastic pipe as I only had the stiff 15mm stuff and would not have been able to get tight enough bends.
Would you say that the 15mm plastic pipe that has quite a thick wall can get as hot as a piece of copper pipe with same temperature water inside. I am only guessing but I think the copper conducts the heat better.

I copied this from internet:

Good conductors of heat: Copper, gold, Aluminium
Insulators (poor conductors): Wood, plastic, glass, china, cork
A saucepan is made of aluminium or copper which is a good conductor of heat.
The handle is made of plastic or wood which is a poor conductor

 

[Agile]

Copper conducts heat far better but thats not the point.

The heat output is limited by the lesser thermal resistance of the floor covering so the rather higher thermal resistance of plastic tube is not a major factor on UFH.

Tony

 

[motorhomes4sale]

Copper conducts heat far better but thats not the point.

The heat output is limited by the lesser thermal resistance of the floor covering so the rather higher thermal resistance of plastic tube is not a major factor on UFH.

Tony

So for the job I have done.
If I had used some plastic pipe under the floorboards could I have got the floor surface as warm as it gets now ? (it gets very warm ) The outside of the plastic pipe I don't think would have got as hot so how would the floor get as warm ? Plastic is one of the worse conductors of heat and copper is one of the best. I know I have a wooden floor and this is one of the worst conductors of heat but theres nothing I can do about that. All I could do is try and get as much heat as possible underneath.

I would like to measure the surface temperature ( not the bathroom air temperature ) of the floor to let you guys know just how well it works. What sort or therometer could I do this with ? maybe a stick one or one of those food pointed ones, any ideas ?

 

[hammerswinger]

...I would like to measure the surface temperature ( not the bathroom air temperature ) of the floor to let you guys know just how well it works. What sort or therometer could I do this with ? maybe a stick one or one of those food pointed ones, any ideas ?

You would use an Infrared Thermometer like this :
http://www.maplin.co.uk/module.aspx?moduleno=220790

Take a look on ebay for this type of thermometer as there is loads of them for sale.

My thoughts on UFH....
It was originaly designed to be fitted within the slab of a solid floor, the slab heats up & acts as an emitter which works very well.
This is however limited to new builds as no one is going to dig up their solid floor to install heating, well maybe one or two would but not many.
So the manufacturers of UFH products have quite a limited market (new builds) so they designed a system that could be fitted under timber floors by using insulation & spreader plates etc, this will never work as well as when it is fitted into a solid floor despite what they will tell you.

The system you have installed under your bathroom floor will warm the floor nicely & quite quickly, as you know.
I'm of the opinion that if you had used plastic pipe your floor wouldn't have got as warm & it would have taken longer to warm up, no matter what the science says.

Cheers.

 

[motorhomes4sale]

I don't know if this will work but it only cost me £1.39

Temperature range looks about right

When it arrives ill stick it down on the cold floor then turn on the heating, ill see what it gets to to after 30 minutes, 1 hour, 2 hours etc.

http://cgi.ebay.co.uk/STICK-AQUARIU...m&pt=UK_Pet_Supplies_Fish&hash=item2eac5e67e9

 

[Agile]

The digital one would have been far more versatile.

Its not that easy to measure floor temperature except with a simple thermocouple probe because its important not to alter the temperature when measuring it.

Tony

 

[motorhomes4sale]

The digital one would have been far more versatile.

Its not that easy to measure floor temperature except with a simple thermocouple probe because its important not to alter the temperature when measuring it.

Tony

Thanks.

I will see if I can borrow one of those of someone

 

[spudkey]

Ufh flow tempreture and pipe spacing are designed to give the required output for the room. However the limiting factor is floor temp.
Most ufh systems have some control over flow temp (less than 55)
Floor Tempretures above 28c can damage floor coverings and lead to deep vein thrombsis.

 

[motorhomes4sale]

Ufh flow tempreture and pipe spacing are designed to give the required output for the room. However the limiting factor is floor temp.
Most ufh systems have some control over flow temp (less than 55)
Floor Tempretures above 28c can damage floor coverings and lead to deep vein thrombsis.

On top of the pipes is 18mm chipboard + 6mm plywood and I have used the proper high temperature glue for the Karndean.

 

[LittlePlum2]

Err...thought the point of underfloor heating was to do away with unsightly surface mounted pipes/radiators and erm......towel rails...dohhhhhhh!!!!

 

[spudkey]

Very few bathrooms have a large enough floor area for ufh to give enough output to cope with bathroom design tempretures and air changes so additional form of heat is required