Are new builds more energy efficient?

If you’re looking to buy a home, you’ve probably come across the question: are new builds more energy efficient? And because energy bills and environmental impact are so closely linked, it’s natural to wonder too where new build homes are new sustainable?

The short answer is, new homes are usually built to much higher standards than older properties - typically with better insulation, more efficient heating systems, and modern building methods that reduce wasted energy. However, there’s more to it than that. Energy efficiency can vary between developments, and not all “new” homes automatically mean “green”.

In this guide, we’ll talk through what makes many new build homes more energy efficient, how EPCs and green mortgages work, and what sustainability can look like in modern developments - including approaches we use.

In this section:

• The energy efficiency of new build homes
• Energy efficiency, EPCs and green mortgages explained
• Are new build homes more energy efficient than older properties?
• Why are new build homes more energy efficient?
• FAQs

The energy efficiency of new build homes

Energy efficiency is really about one thing, how well your home holds onto heat and how much energy it needs to stay comfortable.

Many older homes lose warmth quickly through walls, loft spaces, floors and windows. That means heating must work harder, and stay on longer, to keep rooms warm. New build homes tend to do the opposite. They’re designed to hold heat in and keep cold air out - which helps reduce energy use without you having to constantly adjust the thermostat.

This isn’t just a “nice to have”. A more energy efficient home can genuinely change how a property feels to live in. Rooms heat up faster, temperature stays more consistent, and you’re less likely to have cold spots or persistent draughts. Over time, that can make a real difference to running costs too.

EPCs and green mortgages explained

What is an EPC?

An Energy Performance Certificate (EPC) gives a home a rating from A to G, with A being the most energy efficient. It’s designed to show how expensive a home could be to run, and where improvements could potentially be made.

EPCs are based on factors like insulation levels, heating systems, glazing, and whether renewable energy technology is in place. Because new homes are built under modern regulations, they often score higher - typically between A and B - while older homes are more likely to fall into the middle bands unless they’ve been upgraded.

If you want a quick indicator of whether a home is likely to be efficient, the EPC is a solid place to start.

What is a green mortgage?

A green mortgage is simply a mortgage product designed to reward People buying energy efficient homes. Many lenders do this by offering incentives - like lower interest rates, cashback, or reduced fees - if the home meets a certain EPC rating.

The logic is pretty easy to understand: an energy efficient home often costs less to heat, which can make day-to-day budgeting more manageable. Some lenders factor this into affordability and risk.

Not every lender uses the same criteria though, so if you're interested in a green mortgage, it’s worth checking exactly what EPC rating they require.

Are new build homes more energy efficient than older properties?

In most cases, yes - new build homes are more energy efficient than older properties. That doesn’t mean older homes can’t be improved (many can), but it does mean new homes typically start from a much better baseline.

A lot of traditional housing stock was built long before today’s energy standards existed. That’s why you often hear about older properties being harder to heat, especially during colder months. Single glazing, solid wall construction, older boilers and general draughtiness all add up.

In contrast, new build homes are designed with performance in mind. They’re built to stricter standards for insulation and airtightness, and they usually include modern systems that are simply more efficient.
It’s not unusual for Someone to move from an older home into a new build and notice immediately that the home stays warmer for longer - even with the heating on less.

Why are new build homes more energy efficient?

There are a few key reasons why new build homes often come out ahead, and most of them boil down to how the home is constructed and what it’s fitted with. Here are just some of the most common reasons why new build homes tend to be more energy efficient: 

Better insulation and fewer gaps

Insulation plays a huge role in energy performance. New build homes typically include high-quality insulation in walls, roofs and floors. That reduces heat escaping through the structure itself.

Equally important is airtightness. Older homes often have small gaps around windows, doors, floorboards and loft spaces that let warm air leak out and cold air creep in. Newer homes are generally built in a way that reduces these losses, making the home easier to heat and keep warm.

Modern windows and glazing

Most new builds include double glazing as standard, and sometimes enhanced glazing depending on the specification. This helps keep warmth in, reduces condensation, and can improve comfort in colder weather.

Efficient heating and controls

New build homes tend to have modern heating systems (or low-carbon alternatives depending on the development), and they’re often paired with smarter controls. That matters because heating efficiency isn’t just about the boiler - it’s also about how well you can manage heat in your home, and whether you’re heating space you don’t need to.

Sustainability built into the bigger picture

Sustainability isn’t only about what’s inside the home. It’s also about how a development is planned and how it supports People in everyday life.

At Places for People, the focus is on creating Communities where People can put down roots - with design choices that support a better quality of life and longer-term sustainability. Depending on the development, this can include energy-conscious design, thoughtful green spaces and landscaping, and connections that support active travel such as walking or cycling.

Because Places for People is the UK’s leading Social Enterprise, we also have a a wider commitment to creating long-term value for Customers and Communities –that means not just building homes, but creating spaces that work for the People living there.

Final thoughts