SteamyTea

Almost. It does depend on what the losses of the building/room is as well. A floor slab is no different to a wall, except the angle it is at. There is a hot side and a cold side. The hot side is the mean flow temperature (give or take a little bit because it will have some concrete above it). The cold side is the ground, which varies with external temperature, but with a quite long delay/response time. The easy way to get an idea of what the ground temperature is, is to run the kitchen cold tap for a minute or two, then measure the temperature. Underfloor heating is generally considered to use more energy that radiators (which are really convection heaters), the amount extra used is generally considered 20%, but that is dependant on so many other things it is only a rule of thumb, just as easy to work it out more reliably with a thermometer and ten minutes with a spreadsheet.

I worked out if the flow temperature, in an UFH system, was 32°C and ground was 8°C, the with a U-Value of 0.27 W/m2K, then it is about 400 W lost to the ground, and at 0.12 W/m2K, then 175 W will be lost to the ground. So about half the losses with better insulation. That is probably a worse case, so maybe halve it. But if you have less insulation, the mean flow temperature will probably be higher, so even greater losses. Insulation is not an exciting product, but it works all the time and consistently. While it might be easier to say that the losses are relatively small in the scheme of things, having UFH in the house will probably make it a nicer place to be.

Yes.

How many m² and what is the ∆T.

That could be any size though.

Holier than a........ Just no!

A flue works by having a lower pressure at the outlet than the inlet. The pressure difference is caused by temperature related density changes. Flow rates are affected by the ratio of cross sectional area to circumference ratio, which changes greatly during a bend. Flow rates, or more accurately, mass flow rates, are complicated to calculated as increased velocity can actually stall the system. Much easier to just put a fan heater in.

Must I insert the thermometer to prove it, again, again, again. The difference between an oral and anal thermometer. The taste.

About the same as ore body temperature. But I have a hot body. That may be how you make a pasty, not how thy make them down here. No one knows what goes in them.

For me 37⁰c starts to feel chilly.

Make the slab the size, and shape, you really want, then build to just under 30m2. Not sure how well you want to insulate it, and if that has to be inside the foot print or outside. If you make it of TF, or SIP construction, it should be easy to make it longer then no one is looking.

I might sound like Bruce Willis, but I have a much better memory.

When I was at school, we used to call people that finger pointed 'sneaks'.

And I thought that special orange message about behaviour on here was directed solely at me.

You as well as @pocster Will budgie smugglers be allowed again.

GRP every time. Think of it as a boat. Do you want something that is capable of being sailed around the world, or something that almost makes it across the Channel. You do need to get it done properly, and that is where the challenge is.

Do some measuring and the sums. Td = T - ((100 - RH)/5.) where Td is dew point temperature (in degrees Celsius), T is observed temperature (in degrees Celsius), and RH is relative humidity (in percent).

Fit two, separate ones. One near the boiler, and one in a suitable living area.

Let us know if it works, and is a practical solution.

Do you have two separate businesses, one for quotes and one for contracts. I just hope my pension find invested wisely in energy production companies, and now pulls out of them.

Not to be too controversial, but isn't HS2 really just a reflection of our under investment in the rail infrastructure. The kind of thing that we should have done decades ago. Unlike Wales and its roads, where all development is stopping.

My house is a 7.6m [D] by 3.5m [W] by 5 m [H]. Probably not legally large enough to keep pigs in now.

By picking the cheapest (at the time) generation method, the idea was to set a target for other generation technologies to aim for. Been a good policy as wind and solar had surpassed the 'cheapest' generation type. Only nuclear is given special treatment now, and I doubt that will happen again. Just taking EDFs generation profits of around £1bn for the last year, it is peanuts compared to the £23+bn they are spending at Hinckley. I think Centrica paid close on £1bn in corporation/windfall tax, in top of all the other taxes they normally pay i.e. VAT, employee taxes, business rates, vehicles etc.

I wish I had stayed in the West Indies. Heating system, not needed. A/C could probably be designed out. Energy cheaper than water. Coral reefs to swim over. Sailing in warm weather. Best Rijsttafel ever.