SteamyTea

That gets me to @Pocsterland, or about a third of my bi-monthly trips up country. I find filling my mind with thermodynamics problems passes the time.

Is this New Year confession time. I drilled though a wall to install a water pipe for a shower, long drill bit. Went through the wall fine, and then into the 300lt cylinder that was the other side. Measure twice, drill once.

I just knocked it up from assumed k-values. It is a 1D model, so edges, which can have greater losses, would need to be added on. I think that is caused by the charting software, see below for a different curve algorithm (changed to a B-Spline from a Cubic Hermite Spline). This is where it gets difficult. It depends, primarily, on energy prices and installation prices. UFH would cause greater losses than just heating the air in the building, the building form factor would make a difference as well. This is why individual buildings need to have heat loss calculations and not have the heating system sized by a rules of thumb i.e. just floor area or number of windows (I have heard a plumber assess the heat loss that way). Losses though the slab are uneven as they can be affected by the room temperature above, the ground type below and if there is any ground water movement nearby. So probably safer to pop a bit extra in, rather than too little.

Use this simple cut out guide to work out your ideal insulation thickness for your desired U-Value.

No idea. Would be OK for windows and doors, but not very good for slab insulation.

You are still comparing overall thickness though (I know you had a (expletive deleted) up are limited on thickness). What you need to do is pick a U-Value (i.e. 1.2 W/m².K) and compare the prices to achieve that, not compare prices to fill the gap up. Not if you had made that decision in 2015, 6 years before our energy prices doubled.

Have you work out the price by U-Value, rather than thickness. Regarding unfaced sheet. Unfaced are used a lot in the composite plastic industries because it is easier to adhere to. For any sheet insulation there will be a certain amount of compression when the initial pour of concrete is added over the top. There has been some discussion in the past about whether it should be polystyrene first then PIR, or the other way around. I can't remember what the outcome was, but seemed to remembered it was counterintuitive. The insulation manufactures should have that information. There will also be a long-term creep as well. PUs can keep shrinking for years. They also absorb moisture (as do most materials) that can affect the k-Value quite significantly. I think polystyrene is a bit better in this respect (though it does depend on density. It really comes down to what you want from your floor insulation. I am with @JohnMo in this respect. Get the very best performance you can financially justify, you can put it right later.

If you read the work of J Richard Gott, he states that the longer than something has been about, the longer it will last. AC lighting has been around a long time compared to modern DC lighting. So you have to consider the replacement costs, the potential difficulties of getting like for like replacement, separate wiring circuits etc etc. You can buy, from Poundland, LED builds that plug into an ordinary bayonet or Edison Screw fitting for a pound. Why complicate things, it is a light build.

Bullshit Jobs

Several years ago, a neighbour of mine was working for a large, London based legal company. She had it written into her contract that she could use the companies IT facilities to do her Amazon trading. One of her duties was to post many legal documents, she used to slip in her own packages with no one noticing.

Isn't OFGEM meant to put a cap on it on predicted future prices (they are not really predicted as they are forward contracts as far as I know).

Right. Does still make me wonder if, with true WiFi connected system, if the routers are getting overloaded. I know when I have more than 5 things connected to mine, it gets unreliable. This has happened with both a real router and using my phone as a hot spot. My newer hotspot phone has the option to specify how many devices can connect to it. It has been much more reliable than my old phone (but let range) but I do only have about 3 things connected at any one time now. I did play about with Node Red a while back, but got bored.

If the problem is loosing local WiFi connection, would a dedicated router sort the problem?

Welcome. Brilliant. Hunt around on here and start dispelling many of the myths about this wonder product. My chemistry is not good enough to fully appreciate just how useful it is.

Just one, looks like she has a large nut cracker

A few minutes looking at the data and it shows a messy picture. But generally, the trend is that the more RE generation there is (less fossil fuels) the cheaper the kWh price is in the USA. It is messy because of the different stages each state is in implimentaion, amount imported from neighbours, and climatic differences.

Maybe they need to install some more capacity. https://en.wikipedia.org/wiki/List_of_U.S._states_by_electricity_production

Welcome Is there a reason that you have chosen Structural Insulated Panels and not other methods of construction?

The pictures are better on radio. One problem solved. Fires in homes are coming under more scrutiny and legislation, so why bother. Another problem solved.

As you are not using natural gas, have you thought of Air to Air Heat Pumps? Regardless of what system is used, plenty of floor insulation will help, best to get it done early as it is hard to add it into a slab later.

The consultation on the new regs finishes in a few days time. https://www.bbc.com/news/articles/cev8mrgky9eo

Will the thickness of the tiles affect the height of where the stairs finish?

Never heard of MIMO, but then, IT people are like chemists, except they just use letters. Multiple input, multiple output https://en.wikipedia.org/wiki/MIMO

Are the nails there for a reason i.e. holding the timber in place. Used in proper engineering all the time. Cost a bit more but are good.

The useful efficiency will be pretty poor initially as little condensing may be happening. The 12.5 kW you have limited to may only be a rough setting and is the thermal output. The efficiency may be down to 65% at start up, which is getting close to 20 kW. Or Was it heating water then?