heating system for new house

romeonovember

Hi there,

we are in planning for a 2900square foot house with a provisional BER of A2. in relation to the heating system I do not want to spend 25-30 k putting in an expensive geothermal heating system if we don't need to and will be a waste of money in a super insulated house. I was thinking of the following system:
solar panels for summer hot water - thinking of evacuated tubes over flat panels.
oil condensing boiler with astethically pleasing radiators.
stove in kitchen/diner/den area for local heating.
Insert stove in living room with possible back boiler that would aid winder heating to the large buffer tank.
the house is orientated to maximise solar gain.
Opinions would be greatly appreciated.

jameser123

Air to watet heat pump and underfllor heating.cost approx 16 or 17 k maybe

jameser123

Air to watet heat pump and underfllor heating.cost approx 16 or 17 k.
Not far off what u proprosed. Plus not always as simple as that when trying to make compliance

kscobie

Condensing Pellet boiler is about €6k, 6-26kW, there is a 4-16kW also but they have not it out yet, no idea of cost, but if its smaller, it should be cheaper, would allow you to have all above, with the pellet instead of the oil

antoinolachtnai

You really need the advice of the architect or engineer.

But I would observe the following. In principle an A2 rated house of 280 square meters will only use around 40kWh/square meter = 11200 KWh/year. You will already be putting around 4500 kWh into the house in ordinary domestic electrical usage (this is the national average, just running washing machines, cooking, lighting, etc), so you will only be 5700 short.

In reality, your heat requirement may be much less than 11200 kWh/year (strictly speaking primary energy per year). You may only need heat for a few days a year. A few electric heaters might well do the job. Unlike a regular house, your house will hold the heat, so if you applied heat to it at night at nightsaver rates, that might be enough to keep it warm.

It sounds mad but electric heat has very low capital costs. It's got the perception of being an expensive form of heating and it is, but if you are going to require very little energy per year, then the actual energy cost may not be that important. It also doesn't have any ventilation issues, as stoves will have.

Why spend 15 or 20 grand on a heating system for a house that actually requires damn-all heat?

Using electric heating could drive your BER down a bit however, because it effectively consumes twice as much primary energy to provide the same level of heat.

You could plumb for oil central heating or a heat pump, and then only actually install it if you find it is required after a season or two.

I would be concerned about ventilation, since your house will presumably be very well sealed.

ChippingSodbury

Hi,
We moved into our new house in Feb this year. It's around 3000 sqft. We have good solar gain with our design. We have an MHRV system installed, a 12kW solid fuel stove and 26kW oil fired condensing boiler, solar panels.
It took a while to increase the temperature in the house when we first moved in but we haven't had any form of heating (house or water) on since mid-April. At a guess, I don't envisage turning on heat for another month. We also put in an electric shower in the main bathroom to cater for times when there isn't enough hot water from the solar panels: quite useful.
We got a few of these radiators: http://www.theradiatorshop.ie/product.php?id_product=358, good service and price, they look and work well although they're a bit on the dear side when you compare them to "ordinary" rads.

romeonovember

hi,
thanks for all the replies. Just curious ChippingSodbury as to the type of wall construction you went for and the u value of same?
thanks

ChippingSodbury

Hi,
Nothing too fancy: I think it's an 8" cavity pumped with bead, don't have the details to hand. Windows are triple-glazed from Munster Joinery U-Value around 0.8 if I remember correctly. Air tightness membrane fitted also. One point regarding that: when fitting the windows, pay attention to the way the air tightness tape is applied around the window frames. We ended up trimming around the junction between the plaster and the frames to hide the protruding excess tape. If the tape was fixed to the frames before fitting, you might avoid this problem.

alemap83

ChippingSodbury wrote: »

Hi,
We moved into our new house in Feb this year. It's around 3000 sqft. We have good solar gain with our design. We have an MHRV system installed, a 12kW solid fuel stove and 26kW oil fired condensing boiler, solar panels.
It took a while to increase the temperature in the house when we first moved in but we haven't had any form of heating (house or water) on since mid-April. At a guess, I don't envisage turning on heat for another month. We also put in an electric shower in the main bathroom to cater for times when there isn't enough hot water from the solar panels: quite useful.
We got a few of these radiators: good service and price, they look and work well although they're a bit on the dear side when you compare them to "ordinary" rads.

Hi ChippingSodbury,
Can you tell me what stove you inserted please? We are starting to build a 3000 sqft house as well. We were planning to put a solid fuel range in the kitchen and use this along with an oil fired condensing boiler to heat our house. Unfortunately we cannot find a range suitable for an airtight house. So looks like we will have to go with a stove instead.

Digger40

Hi guys, anyone know where the best place to go for an insert stove. I tried hearthandhomes in lucan but they have a terrible service..Any ideas appreciated

ChippingSodbury

Hi,
We put in a Stanley Tara with an external air kit. It's 12kW, I think 8kW to the boiler and 4kW to the room (which isn't a lot to the room so if you're looking to be melted, you'd need more room output!). Bear in mind when going for an external air kit, you also need to provide ducting to the outside (preferably two external walls) which the builder will need to fit under the floor. If it's fabricated, there'll be a cost associated too.
We bought our stove from http://www.flamefireplaces.co.uk in Enniskillen. As far as I know, they'll deliver anywhere in the northern half of the country. They have a good selection in their shop and we found them more than helpful.

Digger40

Cheers I'll check them out

romeonovember

Hi There,

I am getting to the stage where we are agreeing on the heating and HW system. We are going to go with circa 8m2 of solar collectors, a grant vortex oil boiler and a wood burning boiler insert stove to get the Part L over the line. the problem is that my architect is asking for the ancilliary certifier to sign off the system; Grant will design and sign off on the oil boiler, the solar and the thermal store, but not the wood boiler stove, so herein lies the problem. has anyone encountered this under the new regs. as I would be interested to see how you got over this problem.

thanks,

Romeonovember.