I've spoken to few heating engineers but their talk is mostly as sales people so wanted to hear some real life experience from people on EF.

A 1970s house, poor insulation (F or G rating), heated by radiators and fuel oil. Burner replaced 3 years ago and according to owner it was the most cost effective heating solution on the market. Consumption is 8 tons every 18 months or so. Hot water comes from the same heating unit. Heated floor space is around 280m2.

If floor gets replaced, is putting underfloor heating any advantage? Some say it is more modern, other say it is not very adapted for a old house with high ceilings which is not insulated like the news ones. One says it is a shame to ditch the almost new oil burner for a heating pump which uses electricity and the floor will get 35C temperatures contrary to the 70C in the radiators and if it is to combine both there will have to be a system which sends lower temperature to the underfloor and high temperature to the radiators.

Any real life experiences?

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"FAQ is not binding."

I have electric heating via radiators and it’s fairly efficient. Our insulation is also crap. My understanding is underfloor which cannot be electric now has to be heat pump will not create enough heat unless you have good insulation. Cost of insulating house = at least 60k. Cost of heat pump and floor heating install = 50k approx. savings = max 1.5k per year. Therefore payoff of investment = 75 years.

I rest my case.

We have similar - a 1970s house but which was renovated and has underfloor heating but a couple of radiators in the basement. The oil boiler does hot water and supplies the radiators (hot) and the underfloor heating (warm)

When you say you've got a new burner, do you mean the whole unit (called a boiler in the U.K, or just the burner element?
Most modern oil-burning boilers can do underfloor heating. It's the external valves that do the heat control.

If you've never had underfloor heating then you're in for a treat as it's so nice in winter. It does make the whole house feel warmer.

You get extra wall space as well losing the radiators.

The cost though is huge, especially as you'll need to replace all the floor coverings (tiles, etc) as well.

We considered a heat pump too but it's probably not going to work well in an older, less well insulated house.

This is what I slowly start to realize. I speak with engineers, they tell me how it can be much more efficent, new material, etc etc only when I ask what would be the real world savings and how many years to get back the investment (because the new system/insulation also has a useful life) the numbers are unbelievably poor.

I need to check if the boiler was replaced but I would think only the burner element.

so in that case underfloor heated by fuel oil would be sufficent in an old house even without radiators. Having lived in both, would you say underfloor heating is a major upgrade for a house worth the hassle?

__________________
"FAQ is not binding."

Have you any figure to back this up ?
Direct electrical heating appears not to be recommended (Ger.) https://topheizung.ch/heizsysteme/elektroheizung/

Isn't direct electrical heating forbidden in most cantons now ?


Even if it isn't their is a lot of noise about outlawing it

I can't answer whether it is worth the hassle as for us, it was done by the previous owner.

You probably wouldn't get back the money when you come to sell but it would make the house more pleasant for you to live in and would certainly make it more attractive to buyers when come to sell it.

If you are planning to live in the property for 10+ years, then the feel warm factor is probably worth paying for, regardless of how good an investment it is. The same is true for a new kitchen or bathroom.

My house gets an electricity bill of around 3k per annum. So roughly 275 per month.

I think this is reasonable. I asked the gas company they said gas would cost as much or more and that’s without installation. Heat pump needs electricity to run so may reduce the bill by say 50% but it isn’t powerful enough and not much saving for overall investment.

We have floor heating, geothermal heat pump (PAC) and pay around 1200 CHF annually for our home built 7 yrs ago

Yes this is a great comparison. We’d love a geothermal but it’s 80k for a geo install using radiators not underfloor and it saves us 1800 a year. I totally would love it and I live in jealousy for the lovely warmth it brings you but the numbers just don’t add up for a full install and insulation upgrade.

I can't help thinking that, in the coming years, the "cooling" costs will be more significant that the "heating" costs.

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Geothermal looks absolutely brilliant but simply won't work for an old house. The insulation can never be on par as a recent builds and only a third is saved in the operating costs.



The more research I do it seems smart to add floor heating to the existant heating oil burner and keep the radiators. Have the floor system run on the same burner only with reduction in temperature. As floor needs to be changed it won't cost that much extra to put in the heating.

When I was still living in Switzerland, we had a house with underfloor heating and I hated it. There was so much inertia in the system that the temperature in the house needed more than 6 hours to start to react to what I adjusted the temperature to. It was pretty well insulated, though.

So having it warm during the mornings and evenings and cool at night never worked for me. I felt that I must have wasted a lot of oil by keeping the house warm, while we were out working or in bed sleeping. I wanted my radiators back so badly

But if you're someone who likes it warm all day round and you sleep well in a heated room, then this surely is for you. The cost of installation and ownership is something that you'll have to do the maths about. Don't forget the chimney sweep; their bills can add up, too.

Once set correctly, it should never need adjusting.

We've always got round that by turning the heating off in the bedrooms and keeping the bedroom doors closed.

I like to sleep with the window open summer or winter and doing it any other way would be a waste of energy.

Our system (air heat pump and underfloor heating in a well insulated 12 year old house) runs all year round without adjustment.

The various variable were set in the first year. Now 15v hours at above or below 16° Is when it switches from winter to summer mode and visa versa. Each room is set with a thermastat, so bedrooms are cooler, bathrooms warmer.

All that said the OP situation sounds like it will need considerable investment…

How long does the facade have to live, don't they last around 5 decades? Do you plan to improve insulation upon its renewal?

Yes, it is a considerable investment. 2/3 of the floors need to be replaced, which comes to around 30k CHF everything included. While doing that, adding another 25k CHF will get floor heating attached to the current system and additional 10k work to replace doors for the higher ground.

Whether it is worth it to have floor heating in additon to the radiators, that is the question.

Probably in the near future, in 2-3 years

Why would you keep the radiators? You won't need them with underfloor heating and they have a finite life so will need replacing at some time if you don't just remove them.

Living room area is cathedral ceiling and the 1970s build with no insulation at the moment will simply not be enough with floor heating (at 35C), especially for colder weather, it's what most people say.

Even with top notch insulation it will be more difficult to get warm to 22C compared to a new standard build.

Most people are telling me to get a heat pump but that thing runs on electricity so I don't see the point.