Very large gas usage advice

hmontg

We have a 5 bed house approx 4000 sq ft new build Jan 2023. Underfloor heating both levels,thermostats set to 18 and rarely fire,house is comfortably warm. Mech ventilation also. Gas boiler — hot water and towel rails on timers, gas fires which we have avoided using past year. 
Our most recent gas bill was £1509 for 100 days. We used 14380 kwh…where are we going wrong or is this just normal? We really want to reduce our usage since bills approx £6000 for the year for gas. 

Hoenir

Open plan living areas? 

QrizB

You have a very large house, 4x bigger than the average, so should expect larger gas bills.

14000kWh for the coldest quarter of the year doesn't sound especially high, considering the size of your home.

If you're certain that you haven't knowingly used that much gas, it would suggest that you have a leak; either of gas, or of hot water.

hmontg

Ok this is reassuring, thank you. I realised it isn’t average size but also feel it is quite efficient and also we aren’t overindulging in heat and constant hot water…if it’s just the cost of running the house I can accept it. 

hmontg

Hoenir said:

Open plan living areas? 

Yes open plan kitchen living dining but zoned UFH. 

Hoenir

hmontg said:

Hoenir said:

Open plan living areas? 

Yes open plan kitchen living dining but zoned UFH. 

All the air will be heated whether you need to or not. 

hmontg

Hoenir said:

hmontg said:

Hoenir said:

Open plan living areas? 

Yes open plan kitchen living dining but zoned UFH. 

All the air will be heated whether you need to or not. 

Ok yes I get you re. this

Scot_39

Whilst it could just be size and layout as above.

As a more apt guide than the standard Ofgem TDCV in the headlines these days - they actually produce figures for 3 dwelling groupings.

The larger size Ofgem TDCV for duel fuel for instance is 17000 kWh for gas annually - and they give as a guide sizing - for 4-5 people in 4+ bedroom house.

https://www.ofgem.gov.uk/information-consumers/energy-advice-households/average-gas-and-electricity-use-explained

You mention last 3 months - c14400 kWh  - what about the annual total ?

It certainly doesn't sound that outlandish - in context of the 17,000 Ofgem cap guide for potentially slightly smaller home - given 100 days over winter.

If having thought about the size and layout and occupancy levels - you still don't think the house is performing as well as expected - there may be things you might want to think about checking - or have checked. 

In the interim is there anything else you can adjust - like the flow on the ventilation (it's likely of course to be sized for a full house - all 5 bedrooms in use etc - corresponding per person humidity generation etc).

Or if the 5 bedrooms aren't all in use all the time - have you thought about dropping them to say 14/15 - an anti mould rather than sitting / comfort level etc.

And not wishing to worry you - the possibly scarier side of things - hopefully rare - home build issues. In one recent thread re heating costs - only a couple of posts were negative about new build's insulation consistency in practice (small in context of I guess 100,000s homes built annually) see

https://forums.moneysavingexpert.com/discussion/6499562/insulation-issues-in-new-build-home/p1

Reed_Richards

Perhaps the hear recovery part of your MVHR ventilation is not working and you are just blowing warm air out and cold air in?

TheElectricCow

Reed_Richards said:

Perhaps the hear recovery part of your MVHR ventilation is not working and you are just blowing warm air out and cold air in?

It seems unlikely that an installation could be messed up this badly, but it’s a very valid point nonetheless - perhaps check the MVHR unit for any “summer vent” settings that may be incorrectly enabled and have activated in winter.

hmontg

Thank you so much for all of this, I really appreciate it. It was hard to find estimate for house our size as above average so grateful for the Ofgem estimates for larger home. I will check the ventilation and immersions.