ProDave

Those 2 small "tanks" are expansion vessels. This system is starting to sound like one I had to sort out a few years ago. It was a new build, wired by someone else and it had never worked properly with some rooms freezing and some rooms roasting. The basic issue was all the room thermostats were controlling a different room to where they were, it had been set up wrong. To test that theory, go and turn ALL rooms up to maximum and see if any / all get hot.

Gurgles are caused by a blockage of the vent, so the lump of water flowing down the drain creates a vacuum. Normally the vent allows air in, but if the vent is blocked it will suck air in through one of the traps. I assume there is another flat above you? THEY might have a blockage that as well as blocking their flow, has stopped the stack venting? More information if you can please.

You need to start by working out your heat input requirements. @JSHarris has made a wonderful spreadsheet to make this easy, I am sure someone will post a link to it very soon. From that you can wok out how many watts per square metre your UFH system has to deliver and then you can work out pipe spacing etc.

That's the MCS price?

At those U values you will certainly want close spaced pipes in the UFH and will need to run it hotter than many of us do. Definitely pay a lot of attention to air tightness and in particular, don't accidentally construct a "plasterboard tent" inside your stone building with the gap behind the plasterboard open to cold parts i.e. the loft.

That's the company I bought mine from. You will remember the saga I had when mine (different make) turned out to be faulty, but it did get resolved.

OR turn it on now and see if things start working.

What a shame I could not find an architect that thinks like that near me.

My gripe with architects is they would only quote me a full price for the whole job, which was based on their estimate of the build cost (which turned out to be a lot higher than the actual build cost) and they would not negotiate e.g if I only wanted design and drawings and no project management. I ended up using an architectural technician to do the drawings and input from a structural engineer.

That's because less than 30 and they won't feel warm to the touch. If you want the room to heat to mid 20's (which would have m sitting in my boxers complaining it was too hot) you are going to need a floor temprature of 30 or more anyway I suspect. So start with the manifold mixer hot enough you can feel the heat to determine what is ans what is not working, then when it is all sorted and working wind the temperature down a bit.

One posted on another forum (if I can find it I will copy a link) where the reflected light made an image of, well, the first word of the thread title.

I thought the "selective availability" (deliberate scrambling) of the GPS system had been turned off and we were now getting full accurate resolution. but looking at the GPS track from yesterdays sail, at least one leg which I know we sailed straight is showing as a zig zag, and peak speeds of 14 knots (on a 25 foot sail boat, I don't think so) suggests it is not as accurate as we might believe.

Trust me, I have seen worse, a LOT worse. Tile it and see how it looks. At least it's not "offensive"

1mm is better. There is not much room in those wiring centres to get all the cables in, so the smaller the better.

I know this won't help but I don't like those Heatmiser programmable thermostat things. They are complicated beasts to set up. Give me a simple thermostat with a dial, and a separate conventional central heating time clock to set the on and off times (that's what I have in my house)

Okay. The BASICS of how it should work. When you turn a themostat in a any particular room up to the point it calls for heat, that should turn on the manifold that feeds is. So in your picture 3, whatever room is connected to zone 1 is calling for heat, so the manifold pump should be running (you should be able to hear that) the pipes should get warm, and you should see one or more of the flow meters (the things with glass tubes along the top of the manifold) showing that water is flowing (may take a couple of minutes for the flow to show as the thermal actuators are a bit slow) So lets start with that manifold in picture 3, is the pump running, are any pipes hot and are any flow meters showing water flow? The other manifold that does not have a power light, that is your first challenge to find out why there is no power. Is a switch turned off anywhere? Id there a programmer or time clock that has not been set to come on? Top left on the manifold is a pressure and temperature gauge. What does the temperature say (that is the flow temperature in the heating pipes)

As it shows, you need a 3 core and earth cable from each thermostat to the wiring centre. L on wiring centre to thermostat terminal 1 N on wiring centre to thermostat terminal 2 L1 on wiring centre to thermostat terminal 4 No connection to the thermostat terminal 3 That is it. Repeat for each room stat. The wiring centre is providing power to each thermostat and reading it's output.

I am not best placed to comment on the requirements for a competent persons scheme. There is no Part P this side of the border, so no requirement to be a member of such schemes, and for a new build, building control just accept an EIC that I issue, based on the model forms in the wiring regs. This puts me in the rather bizarre situation that I could not just hop over the border and do a new install in Carlisle without paying lots of money to join one of these schemes. Since I have a maximum of 4 1/2 years to go until I plan to retire, I am just keeping my head down and carrying on as I am and hope nothing changes in that time to force scheme membership up here.

That's an unusual layout in that the only access to the rear (and the old lean too) is through the small bedroom. Just making the 2 bedrooms longer is not going to achieve much. Can we have a plot layout? A side extension would make a lot more sense but I am guessing there is no room to do that?

My own trailers (general one and boat trailer, now gone) were both built in the stone age before sticking plates on them was mandatory. Both have survived a long time doing what they were built for so it is safe to say they are adequate. But I have never been pulled or had a trailer examined. A caravan trailer will have a Maximum Technically Permitted Weight on it's plate. Once you have stripped the caravan body off and made it into a trailer just get it weighted, and the load it can carry is the MTPW less what the trailer actually weights. You will probably find the load capacity is not much. BUT I know at least one old caravan chassis now used as a boat trailer, I am SURE that will be over it's load.

Thank you for finding that. It's been filed away should I need it.

I had forgotten I posted that.

I am not sure I understand the question. It is a proven system in use and marketed in many places. as to "approved" well it was detailed on the building warrant and agreed by building control.

A few things you need to consider. First is racking strength and second is vapour permeability. These were dealt with as a "system" by our designer. The end result was the OSB racking layer (actually 2 layers) is in the inside of the frame as the OSB is less vapour permeable. The Wood fibre on the outside contributes almost nothing to the racking strength and is more vapour permeable than the OSB

You are obviously not in the "hot flush" phase then.