How to keep your house warm: Sustainable energy house tips

25 July 2025

Keeping your house warm during the winter months is a top priority. If you are just starting your journey towards a sustainable home, there are plenty of ways to increase warmth and reduce your energy bills, while also helping the planet.

Why a sustainable house matters

Upgrading your home’s energy efficiency isn’t just about comfort. It’s a smart investment in your future and the environment. Whether you're retrofitting an older home or building new, sustainable energy upgrades can make a big difference.

The benefits of a home energy upgrade

• Lower energy bills all year round. Energy-efficient upgrades like insulation, double-glazed windows, and heat pumps reduce the amount of energy needed to heat or cool your home, leading to significant savings over time.
• Warmer and more comfortable living spaces. A well-insulated home maintains a consistent indoor temperature, eliminating cold drafts and hot spots. This means a cozier, healthier environment for you and your family.
• Grants and support available to help with upgrades. Many governments and local authorities offer financial incentives, grants, or low-interest loans to support energy-efficient renovations. These can significantly reduce the upfront cost of improvements.
• Energy upgrades can boost your home’s value if you want to sell in the future. Homes with high energy ratings are increasingly attractive to buyers. A better BER (Building Energy Rating) can make your property stand out in a competitive market.
• Supporting a greener future. Reducing your home’s carbon footprint contributes to global efforts to combat climate change. Every upgrade—big or small—helps reduce greenhouse gas emissions.

How to assess your current home insulation for better energy efficiency

Now that we’ve explored the many benefits of upgrading your home’s energy efficiency, you might be wondering where to begin. Before making any upgrades, it’s important to understand how well your home retains heat. Poor insulation can lead to significant heat loss, resulting in higher energy bills and colder indoor temperatures. Heat often escapes through hidden gaps, draughts, and poorly insulated areas. A thorough inspection can help you identify where improvements are needed. The most common problem areas include:

• Walls, attic and roof: These are major sources of heat loss, especially in older homes. Check for missing or degraded insulation, and consider upgrading to modern, high-performance materials.
• Windows and doors: Single-glazed windows or poorly sealed frames can let in cold air and let out heat. Look for condensation, drafts, or visible gaps, and consider installing double or triple glazing or using thermal curtains.
• Air ducts: Leaky or uninsulated ducts can waste a lot of energy, especially in homes with central heating systems. Sealing and insulating ducts can improve efficiency and comfort.
• Chimneys and fireplaces: While charming, these can be a major source of heat loss if not properly sealed when not in use. Consider using chimney balloons or dampers to prevent warm air from escaping.

You can get a professional home energy assessment by contacting an SEAI (Sustainable Energy Authority of Ireland) registered provider. The SEAI registered provider will carry out an assessment, provide you with a Home Energy Summary Report, and apply for your SEAI home energy upgrade grant(s) 

Simple everyday tips to keep your home warm and cozy 

Small changes can have a big impact. These are small tricks you can start with before making bigger upgrades.

• Seal air leaks around loose windows and doors: Use weather stripping or draft stoppers to block cold air from sneaking in. Even small gaps can lead to significant heat loss over time.
• Layer floors with thick rugs to trap heat: Rugs act as insulation, especially on hardwood or tile floors. They help retain warmth and add a cozy feel to your space.
• Close doors to unused rooms to stop heat from escaping: This helps concentrate warmth in the areas you use most, making your heating system more efficient.
• Use thick curtains and draw them at night: Heavy, thermal-lined curtains can prevent heat from escaping through windows. Drawing them at night adds an extra layer of insulation
• Rearrange furniture to make the most of heat sources: Avoid blocking radiators or vents with furniture. Position seating areas near heat sources to maximize comfort.

Explore energy efficient home heating and insulation solutions 

• Wall and attic insulation: Since most heat escapes through the roof, insulating the attic is the ideal first step. It's recommended to install between 300mm – 400mm of insulation between ceiling joists. For walls, the two most popular options are external wall insulation and dry lining. Both options effectively improve your home’s warmth and energy efficiency, helping you save up to €600 annually on energy bills. To learn more, check out the SEAI's guide on wall insulation. Grants for insulation upgrades are widely available, ranging from €700 to €8,000. You can read more about the best home insualtion grants in Irleand to support  your needs. 
• Energy efficient windows: With double or triple glazing, the extra layer of glass traps heat, making homes more comfortable during winter months. Thermal foam and airtightness tape block unwanted drafts, so it is essential to use these when upgrading windows.
• Heat pump installation: One of the most effective ways to heat your home and reduce energy costs and carbon emissions; heat pumps work by drawing heat from the air or ground outside and bringing it indoors. To apply for an SEAI heat pump grant, an assessment must be carried out before the work can begin.
• Harnessing solar power: An excellent option if you want to reduce electric bills. There are two types of solar panels available: Solar PV or photovoltaics, which convert sunlight into electricity that you can use in your home. Solar Thermals use the energy from the sun to heat water in your home. The average costs of installing solar panels in Ireland ranges from €6,000 and €18,000. The SEAI offers two grant options to help offset these costs. To learn more about how solar panels work, their benefits, and available grants, check our our guide on solar panels.

Financing Your Home Energy Upgrades

Keeping your home warm doesn’t mean sky high energy bills or complicated upgrades. The SBCI Home Energy Upgrade Loan Scheme from An Post Money offers a low-cost loan with a reduced fixed interest rate, starting from 3.75% APR*. At least 75% of the loan needs to be used for energy efficiency purposes, giving you a 20% improvement in your home's energy efficiency. And you also have flexibility to spend up to 25% of the loan on non-energy related works (e.g. redecorating your home).