New heating system

Monaou2

Hi,

So we have recently taken the plunge and bought a house. It is a ~ 1960's semi-detached in Dublin city.

We have a query regarding the heating system and would love people's thoughts. The current heating system is old electric storage heaters - so a full upgrade will be needed. Would love people's thoughts on what would be the best system to get installed.

A few points to note:
- while cost is obviously important, we want a system that keeps the house comfortably warm, as we feel the cold alot! So are willing to spend sufficiently now to have the correct/best system for years to come.
- There is gas coming to the house, so installing a gas central system would be an option.
- It has a sufficiently large back garden, so could this open up the option for geothermal heating systems or is this just not possible in a typical city dwelling?
- Would it be possible to add underfloor heating throughout the house and is it worth it?
- The current BER rating is F, so alot to improve on here.
- I fully understand that no matter what system you install, if the insulation isn't good in the house then it is a waste of money. Full re-insulation of the house will be done.
- In case it matters re geothermal, there is no access to the back garden from the side of the house....

Any thoughts on the best system to install (gas/geothermal/pumps etc etc) and the key points to consider would be great.

Metric Tensor

In a city geothermal heating would mean a "well" style system where the drilling is done vertically into the ground by a drilling rig. This would be VERY expensive and if you calculate the money it would save over the years the payback period would probably be VERY long. So in my opinion it is not worth it.

Air source heat pumps (which operate on a similar principal just extracting heat from the air) are very popular in new build houses at the moment because they aid in the calculation of renewable energy requirements that are mandatory in new builds. They need underfloor heating to operate correctly and retrofitting this is quite expensive. It means tearing up all your floors and installing pipes and screed both upstairs and downstairs. Your upstairs floors are probably timber and they may need strengthening to hold the weight of a concrete screed.

In my opinion by FAR the best option for you is a high efficiency gas boiler feeding wall mounted radiators with a proper time and temperature zoned control system.

A few points that I think are relevant:
1. None of that is worthwhile unless you do appropriate upgrades to your insulation and air-tightness combined with correct ventilation. Make sure you employ a professional to advise and design as necessary. Don't just take installers words for it.
2. Even for radiators in order to run pipes you will end up doing a lot of chopping and cutting of floors and ceilings. It won't be cheap.
3. You must have an immersion for your hot water at the moment. If you go with a gas boiler it would be worthwhile putting in a new cylinder fed from this boiler (with a backup immersion - that you should never need if the zoning is correct).
4. Although I have no great experience in the area I understand that modern electric storage/direct heaters with a modern programmable control panel can be quite efficient. You could look into this if the costs become exorbitant any of the other ways.


tldr: Opinions will probably vary but mine is that for your needs a gas fired central heating system with radiators is the way to go!

Calahonda52

"We have a query regarding the heating system and would love people's thoughts. The current heating system is old electric storage heaters - so a full upgrade will be needed. Would love people's thoughts on what would be the best system to get installed."
LOL

1: Make sure you understand what MT means in his point one by insulation, airtightness and correct ventilation. This is absolutely fundamental to the project and to understand it correctly you must understand the existing building fabric and how it functions.
2: The correct design of 1 will throw out a heat demand number for the house. Now is your best chance of getting this number down to the lowest number and this will then give you the lowest longterm heating costs.

3: Once you have one and two done it will inform the heat capacity requirement of any installed heating equipment.

4: I agree with MT re gas and rads for your gaff. If the house is being gutted for the pipe work, then you could put an individual wall mounted room stat in each room and have each room as its own zone.

Will it need to be rewired?

Don't be fooled into spending money on fancy kit such as heat pumps, etc.
Keep it simple as per the points above.

Finally, if you are doing new windows, do them in the right sequence and allow for decent insulation on the reveals.

Some light reading:
free
https://www.nsai.ie/S-R-54-2014-Code-of-Practice.aspx

Pay
The first link is for details, second for Irish pricing
https://www.amazon.co.uk/Construction-Technology-Designing-Sustainable-Homes/dp/0717148343/ref=sr_1_fkmr1_1?ie=UTF8&qid=1463079029&sr=8-1-fkmr1&keywords=construction+technology-+trevor+hockey

https://schoolbooks365.ie/index.php?_route_=construction_technology_hickey

The best 35 odd euro you will spend