Underfloor Heating System

ChoosySuzie

We have an underfloor heating system in our house (2,500 sq ft bungalow) which we bought a few years ago.
The boiler is run from LPG - Calor and is insanely expensive (approx €8,000 p.a for the Gas). It has started making strange noises in the last few days and may need changing (11 yrs old). What is the most cost efficient boiler for an underfloor heating system?
Thanks

aujopimur

A modern oil fired boiler is your best bet, a 26kw should should be suffient if you have zoned system.
If you can do it yourself the change over material cost would be about €1700 depending on the location of new/old boiler.

Outkast_IRE

also the reason your spending that much on heating is either you have a massive house or your house just isnt well insulated and your losing heat everywhere , if thats the case consider getting some extrainsulation done.

ChoosySuzie

aujopimur wrote: »

A modern oil fired boiler is your best bet, a 26kw should should be suffient if you have zoned system.
If you can do it yourself the change over material cost would be about €1700 depending on the location of new/old boiler.

aujopimur, Thanks for the response, why oil fired? is it less expensive for running costs?

Thanks

ChoosySuzie

Outkast_IRE wrote: »

also the reason your spending that much on heating is either you have a massive house or your house just isnt well insulated and your losing heat everywhere , if thats the case consider getting some extrainsulation done.

Outkast_IRE, Thanks for the response, I think that we have insulation issues That's next on the list of things to tackle!!

Outkast_IRE

Oh i meant to say i would reccomend oil fired too and get the most efficent one you can , it might cost slightly extra but the bills should reduce slightly more to make up for it.
Also the lpg is proven as prob the most expensive way to heat your home , when changing to oil you would defo see a reduction in running costs. But you will have extra installation costs as you will need to buy an oil tank and may require additonal work to connect to the system .

Get a few professionals in to price it for you , not just one .

Just as a comparisson im in a 3 bedroom semi detached with an old oil boiler and in the last 18 months we have spent only 1600 on fuel .
And we would have it on a lot the last few winters.

aujopimur

ChoosySuzie wrote: »

aujopimur, Thanks for the response, why oil fired? is it less expensive for running costs?

Thanks

LPG is the most expensive fuel, I installed an oil system 4 zones incl U/F + solar H/W nothing fancy in a new 2.500 sq ft 2 storey house, they both work but dont spare the heat and use a non boiler stove in one room during the winter, in 15 mts. they used about 500lts of oil.
The cost I mentioned included an oil tank.

ChoosySuzie

Thank you both, you've been a great help

JohnnieK

Also you can run a HE boiler at a lower temp (because of your underfloor heating) causing it to condense for longer thus reducing your bill more. Do you also have radiators?
Or you could go for a high efficient LPG boiler something Like a Viessmann with a 4 pipe configuration, 2 for heating and 2 for DHW so you are seperating the heating from the hot water. the boiler can be set at a lower temp for the heating and at a higher temp for the hot water.
You should also really think about the insulation too, good insulation is half the battle.
Dose the house cool down quickly?

ChoosySuzie

JohnnieK wrote: »

Also you can run a HE boiler at a lower temp (because of your underfloor heating) causing it to condense for longer thus reducing your bill more. Do you also have radiators?
Or you could go for a high efficient LPG boiler something Like a Viessmann with a 4 pipe configuration, 2 for heating and 2 for DHW so you are seperating the heating from the hot water. the boiler can be set at a lower temp for the heating and at a higher temp for the hot water.
You should also really think about the insulation too, good insulation is half the battle.
Dose the house cool down quickly?

Hi JohnnieK
Thanks for the response.
What is a HE boiler?
No we don't have rads
The four pipe config sounds good too
A lot of interesting points!
Does the house cool down quickly ... very hard to quantify! Quicker than we'd like anyway!
Thanks again

JohnnieK

HE is just short for High efficient, You should really get some one in to look at your insulation. There is no point in spending money on heating systems if the insulation is not going to keep it in.

Hair's Pam

Thanks[/QUOTE]
LPG is the most expensive fuel, I installed an oil system 4 zones incl U/F + solar H/W nothing fancy in a new 2.500 sq ft 2 storey house, they both work but dont spare the heat and use a non boiler stove in one room during the winter, in 15 mts. they used about 500lts of oil.
The cost I mentioned included an oil tank.[/Quote]

Hi just reading your post. We r starting a new 2200sq ft bungalow after winter and I have my heart set on UFH with solar panels and a back boiler in stove. It will be using a new 3 way water cylinder that can regulate the water coming from stove oil and solar. Just wondering do u have more of an insight into UFH as no one I know has it installed.
Do you really need it zoned Into 4 areas or would to be ok e.g kitchen n living area and then bedrooms for night. This would keep the cost down. We got prices in region of 19000 for everything including solar oil tank n burner cylinder valves etc. All except stove.
How does this compare in relation to your UFH. sorry for all the questions but trying to learn As much as possible before we fully commit to it

Thanks in advance.

Outkast_IRE

Hair's Pam wrote: »

Thanks

LPG is the most expensive fuel, I installed an oil system 4 zones incl U/F + solar H/W nothing fancy in a new 2.500 sq ft 2 storey house, they both work but dont spare the heat and use a non boiler stove in one room during the winter, in 15 mts. they used about 500lts of oil.
The cost I mentioned included an oil tank.[/Quote]

Hi just reading your post. We r starting a new 2200sq ft bungalow after winter and I have my heart set on UFH with solar panels and a back boiler in stove. It will be using a new 3 way water cylinder that can regulate the water coming from stove oil and solar. Just wondering do u have more of an insight into UFH as no one I know has it installed.
Do you really need it zoned Into 4 areas or would to be ok e.g kitchen n living area and then bedrooms for night. This would keep the cost down. We got prices in region of 19000 for everything including solar oil tank n burner cylinder valves etc. All except stove.
How does this compare in relation to your UFH. sorry for all the questions but trying to learn As much as possible before we fully commit to it

Thanks in advance.[/QUOTE]
Your looking at the short term costs in terms of zoning, the more zones the better as you have more control.

i have put in systems where the user literaly had control over every single room and long term it saves lots of money as you can set a room thats not in everyday use lower than a room that is in constant use, and they each have their own digital thermostat so if the room is being warmed by the sun or by extra people being in the room the thermostat will sense the room temp is reached and shut off just that room.

In long term cost savings control is the only game in town the more control you have the easier it is to manage the system effectively.

I will repeat the same thing i tell everybody only consider underfloor if
1. you house is going to be very well insulated .
2. You understand it isnt like rads where you flick on the switch for a blast of heat , the idea of underfloor is pick a nice ambient temperature in each room and try to maintain it hence why insulation is so important, and people living in the house understand that if you leave open a window to cool a room it will take a good while for that room to warm up again with underfloor.

If your concerned about prices get at least 3 different recommended plumbers to price it for you and remember cheapest isnt always best, good knowledge and reliability go a long way too.

3. Ensure you have a draft lobby or large porch , as i said maintaining the temp is key and on a windy winters day if you open the front door and its open to the rest of the house , a whole lot of energy gets wasted .

I know you dont know much on the technical side of things but if i was getting solar, stove and oil i would be hooking them all up to a accumulator/buffer tank and heat the cylinder and underfloor from that might be a bit dearer short term but you will gain extra efficiences from the oil , you could get solar tubes and place them at a steeper angle to help gain more use from the winter sun .
Best of luck anyway feel free to ask questions.

aujopimur

+1
I have no idea of the cost as I had no input with regards to prices etc..

Hair's Pam

Thanks for that. The main reason we would like to go with it is due to it's low running temp. So were hoping solar tubes will heat most of the water req during the day n then stove will be light in the evening. Just finding it hard to agree on one kind of system as 3 different plumbers I asked all had different ways of working it. The best looking system we seen so far uses a multi energy tank n they were MD Energy in Kilkenny. They seem to know there stuff and were good at explaining

Outkast_IRE

Hair's Pam wrote: »

Thanks for that. The main reason we would like to go with it is due to it's low running temp. So were hoping solar tubes will heat most of the water req during the day n then stove will be light in the evening. Just finding it hard to agree on one kind of system as 3 different plumbers I asked all had different ways of working it. The best looking system we seen so far uses a multi energy tank n they were MD Energy in Kilkenny. They seem to know there stuff and were good at explaining

If you have the money look at getting your heating system designed by a building services engineer or equivalant person who designs such systems for a living , an amount spent now on this will be paid back by having a proper set of plans for the heating side of things

BMD

Hi,

When looking through any posts regarding UFH, it is usually stated that 'high levels' of insulation should be used. Is there any definition of such 'high levels' as I think most people aren't sure whether they have high levels or not.

Lets assume a cavity block build as this is the way most houses are still being built. What would constitute high levels in this context?

Cavity insulation Thickness?
Dry lining Thickness?
Attic Insulation Thickness?
Ceiling Dry Lining Thickness?
Floor Insulation Thickness?

Lets also assume good workmanship wrt cold bridging etc.

Any opinions on this?

heinbloed

BMD asks:

Lets assume a cavity block build as this is the way most houses are still being built. What would constitute high levels in this context?

The insulation's "level" is non-relevant.
The thermal demand is relevant.
Get a thermal demand calculation done according to EN 12831.
Any other aproach is like palm reading. (" You have a thick skin - good luck ").

BMD

Hi Heinbloed,

This is exactly my point...most posts regarding UFH state that the house should be insulated to a 'high level'...but this is a very generic term. My idea of 'high' could be different to yours etc....what I am trying to get to is a term/value which describes how well a house is insulated...perhaps the BER result is the best tool?

heinbloed

Well, the question is: why asking?

The BER won't give any numbers on the thermal demand of a structure, like the penalty point system won't give any numbers on the gasoline purchase of a car owner.