What are "primary" vs "secondary" measures in the context of grants?

When exploring ways to make your home more energy-efficient, you may encounter the terms “primary” and “secondary” measures. These terms are most commonly used in the context of UK government energy efficiency schemes, such as the Energy Company Obligation (ECO4) or the Great British Insulation Scheme. Understanding the distinction between these two categories is vital for homeowners and tenants looking to reduce their carbon footprint and lower their energy bills.

In simple terms, these categories dictate how grants are allocated. Grant providers generally prioritise high-impact changes that provide the most significant energy savings. By categorising measures, the government ensures that the “fabric” of the building is improved before smaller, supplementary upgrades are funded. This approach is often called “fabric first,” ensuring that heat is retained within the property before new heating systems or controls are installed.

What are primary measures?

Primary measures are the “heavy hitters” of energy efficiency. These are improvements that provide a substantial reduction in heat loss or a significant shift toward renewable energy. In most grant schemes, a primary measure must be installed before you can even consider applying for secondary measures. They are the foundation of a more sustainable home.

Common examples of primary measures include:

• Solid wall insulation: This involves adding a layer of insulation to either the internal or external walls of a property that does not have a cavity.
• Cavity wall insulation: Filling the gap between the inner and outer leaf of a brick wall to prevent heat from escaping.
• Underfloor insulation: Insulating the ground floor of a property to stop cold draughts from rising.
• Loft and roof insulation: Since heat rises, insulating the top of the house is one of the most effective primary measures available.
• Air source or ground source heat pumps: Moving away from traditional gas boilers toward renewable heating technologies is often treated as a primary measure in modern grant cycles.

The goal of a primary measure is to fundamentally change how the property performs thermally. Because these projects are often more expensive and labour-intensive, grants are specifically designed to help cover these costs for eligible households.

What are secondary measures?

Secondary measures are smaller-scale improvements that complement primary measures. While they contribute to energy efficiency, they are generally seen as less impactful on their own than the primary upgrades. Because of this, most UK grant schemes will not fund secondary measures unless at least one primary measure is also being installed at the same property.

Examples of secondary measures include:

• Heating controls: This includes smart thermostats, thermostatic radiator valves (TRVs), and programmers that help you manage your energy use more effectively.
• Draught proofing: Sealing gaps around windows, doors, and skirting boards.
• Hot water cylinder insulation: Adding an insulating “jacket” to your water tank to keep water hot for longer.
• Glazing upgrades: In some schemes, upgrading from single to double glazing, or adding secondary glazing, is classified as a secondary measure.

It is important to note that the cost of secondary measures must generally be less than or equal to the cost of the primary measure they are paired with. This ensures that the bulk of the grant funding is directed toward the most effective energy-saving solutions.

The relationship between primary and secondary measures

The relationship between these two categories is often referred to as the “pairing rule.” You cannot usually “pick and mix” secondary measures without addressing the primary needs of the building. For example, if you wanted a grant for new heating controls but your loft was uninsulated, the scheme would typically require you to insulate the loft (the primary measure) as a condition of receiving the heating controls (the secondary measure).

This structure helps the UK meet its net-zero targets by ensuring that homes are upgraded holistically. It prevents a scenario where a homeowner installs an efficient new boiler but continues to lose all the heat through uninsulated walls. You can find more detailed guidance on how these schemes are regulated on the official Energy Company Obligation (ECO) page provided by the UK government.

Why the distinction matters for your finances

Improving your home’s energy efficiency is a smart financial move. A better-insulated home typically leads to lower monthly utility bills and can increase the overall value of your property. However, the initial cost of these upgrades can be high. This is where grants become essential.

If you are applying for a grant, you must ensure your project follows the specific rules of the scheme. If you attempt to install only secondary measures, your grant application may be rejected. By understanding which category your desired improvement falls into, you can plan your renovation more effectively and avoid unexpected costs.

In some cases, a grant might only cover a portion of the costs. If you need to fund the remaining balance, you might consider various financial products. Before taking on any new debt or making significant financial changes, it is wise to check your current standing. Get your free credit search here. It’s free for 30 days and costs £14.99 per month thereafter if you don’t cancel it. You can cancel at anytime. (Ad)

Eligibility for primary and secondary measures

Eligibility for grants that cover primary and secondary measures often depends on several factors, including your household income, the current EPC rating of your property, and whether you receive certain government benefits. Typically, households with an EPC rating of D, E, F, or G are prioritised for these schemes.

If you are a tenant, you will need your landlord’s permission to carry out any primary measures. Many landlords are keen to support these upgrades as they improve the property’s value and ensure compliance with Minimum Energy Efficiency Standards (MEES). Always ensure that any installer used is properly accredited, as most grants require work to be completed by TrustMark-registered professionals.

People also asked

Can I get a grant for double glazing as a primary measure?

In most current UK schemes like ECO4, double glazing is considered a secondary measure and can only be funded if a primary measure, such as wall insulation, is also installed.

Do I have to install a primary measure to get heating controls?

Yes, under most government grant rules, heating controls are secondary measures that require the simultaneous installation of a primary measure like insulation or a heat pump.

What is the most effective primary measure for saving money?

Loft and cavity wall insulation are generally considered the most cost-effective primary measures because they are relatively inexpensive to install and provide immediate, significant reductions in heating bills.

Is a new boiler a primary or secondary measure?

Under the ECO4 scheme, boiler replacements are subject to strict rules and are often treated differently than standard primary measures, frequently requiring a “broken boiler” status and being limited to certain household types.

Can I apply for multiple primary measures at once?

Yes, many grant schemes encourage a “whole house” approach where multiple primary measures, such as both loft and wall insulation, are installed together to maximise energy efficiency.

Summary of benefits

Focusing on primary measures first ensures that your home is capable of retaining heat. Once the property is well-insulated, secondary measures allow you to fine-tune your energy usage. This phased approach is the most efficient way to upgrade the UK’s housing stock. By taking advantage of these grants, you can enjoy a warmer home, lower energy costs, and contribute to a greener environment without bearing the full financial burden of the improvements yourself.

Always research the specific requirements of the grant you are applying for, as definitions of “primary” and “secondary” can vary slightly between different local authority schemes and national programmes. Planning your upgrades with a clear understanding of these categories will give you the best chance of a successful, fully-funded application.