‘I spent thousands upgrading my 1998 home but it still feels cold – what else can I do?’

Would you like to take part in a free home eco-makeover? Email tom.haynes@telegraph.co.uk

Property owners can hardly move these days without the looming threat of net zero targets.

By 2025, all landlords must have upgraded their properties to have an Energy Performance Certificate (EPC) rating of C. Eventually, the Government wants all homes being sold to have the magic C-rating.

Jeff Thomasson, who lives in Bermondsey, south London, neither wants to sell nor rent his three-bedroom house in the near future. But he is concerned about high energy bills – and is at a loss as to how he can improve his property’s energy efficiency.

He has already made many of the most obvious improvements.

“I built into the loft and had a flat roof extension done,” he said. “At the time of building into the loft, I was looking to install solar panels but was advised that it wasn’t worthwhile given the small footprint and orientation of the flat roof.”

The property was built in 1998, and Mr Thomasson bought it in 2003. Until recently, it did not have an EPC.

Mr Thomasson says: “In 2014 I had all but a couple of the lighting fixtures changed to LEDs. Two years later all but one of the original windows were replaced with double glazing, and in 2020 the original garage door was replaced with a 67mm-thick insulated door.

“But there are still obvious drafts coming from the front and rear exterior doors and the ground floor is always cold.”

Telegraph Money called in the experts to help, including an EPC assessor from Vibrant, outsourced from Skiptons Building Society.

These checks are “nondestructive”, so judgements are based purely on observation. We also asked an energy efficiency expert to give their view.

Ben Heng, Vibrant, said:

I was welcomed at the door to a well-presented property. I entered into a hallway, which led to a downstairs bedroom, the utility room and the garage.

The assessment took around 45 minutes and would include taking photographs around the property to provide evidence for the assessment. The property was fitted with 100pc double-glazed windows and draught-proofed.

In order to carry out my assessment I had to two split the property into two, part of it was over an integral garage, which meant both parts had different thermal qualities, the section over the garage was over an unheated space, but had plenty of insulation.

The boiler was in the utility room. It was a regular boiler that requires a hot water cylinder within the property.

But it was nearing the end of its shelf life, so I proposed the customer could benefit from switching to a combi boiler system. This would provide the customer with hot water on demand, instead of approximately 210 litres of water being continually heated.

The average carbon rating in Mr Thomasson’s location is C74, while his property is rated C76. Compared to the average in his area, the property’s emissions are lower than average.

Potentially, Mr Thomasson could save 1.1 tonnes of CO2 a year, bumping his property up to a B85. This would also reduce his annual energy bill by £746.

I recommend installing solar heating, which can cost between £4,000 and £6,000 and will save you £84 a year. This alone would bump his property’s EPC rating up to C77.

A more noticeable effect could be achieved by installing solar panels, which can cost between £3,500 and £5,500. This would take his EPC to a B85 and would save £662 a year.

However, as we discussed, there would not be enough room on the roof for a solar panel array due to a room in the roof conversion.

Making the recommended changes would cost roughly £9,500 in total, but the investment would pay itself off in under 13 years.

Phil Steele, Octopus Energy, said:

Generally, Mr Thomasson’s home is in really great condition – featuring new double-glazed windows, electric underfloor heating, a new insulated sealed garage door and a brilliant attic conversion.

I took an infrared camera over to Mr Thomasson’s house to find any smaller heating and insulation problems that would be invisible to the naked eye and could be making a big difference to his energy bills.

I started with the garage. While the windows of the garage have all been replaced, the doors of the garage are all still the original ones from when the house was built in 1998.

Due to their age, the doors’ seals are worn and letting heat out at the bottom – so I would recommend replacing them.

I also spotted that the garage ceiling isn’t insulated which means the room above will feel cooler. Mr Thomasson could look into adding insulation to the roof of the garage which won’t cost a lot but would mean the room above it retains more heat. 

The home is a beautiful, open-plan design spread over three floors (not including the attic). With an open staircase all the way up, unfortunately, this does mean a lot of the heat rises and is lost from the lower floors.

If Mr Thomasson wants to fix this, he would have to close up the staircase, but this option needs to be considered as it could detract too much from the overall design.

Since the open design means a lot of heat ends up in the attic, Mr Thomasson really needs to look after any issues with the attic insulation to save from heat loss.

Upon closer inspection, the attic has been insulated with 50mm foam board rather than fibreglass insulation as the thicker layer of fibreglass needed would have taken up too much headroom.

Unfortunately, foam board is hard to cut to exactly the right width and we could see gaps between the insulation board and rafters which are letting out a lot of heat. These would need filling with some more insulation.

The attic ceiling has six spot lamps that are a decade old. As these are halogen the insulation has been cut out around them to avoid heat build-up causing a fire, and there are six holes from where heat was escaping.

If Mr Thomasson switches these to LEDs and plugs the insulation, he’ll be saving in no time.

The bathrooms have older extraction fans that I would recommend Mr Thomasson upgrades. The newer versions have small flaps that close when the fan isn’t in use so will save on any heat loss in the room.

The roof is ideal for solar panels, and two hatches in the attic would be an ideal place to install the inverter [which converts the current generated by the panels so it can be used inside the home] and battery.

Mr Thomasson knows from the original conversion that there’s a gap between his property and each neighbour which makes routing wiring to the electricity consumer unit [the fuse box] on the ground floor under the stairs easier.

Mr Thomasson is in a fantastic position already, but there is plenty he could do if he wants to take it a step further.

Would you like to take part in a free home eco-makeover? Email tom.haynes@telegraph.co.uk