How to choose between cavity wall insulation and loft insulation

Loft insulation and cavity wall insulation are both fantastic ways of making your home more energy efficient. If you are in a financially strong position, it’s worth investing in both. But what if you really can’t afford to install both loft insulation and cavity wall insulation? Which one should you prioritise? Making this choice is even tougher than you might realise, but it’s definitely not impossible.

When you compare loft insulation and cavity wall insulation, there are two factors that you need to consider: the initial cost of installation and how much money that installation will be enable you to save in the long-run.

Loft insulation is notably cheaper to install than cavity wall insulation. According to the cost-comparison website MoneySavingExpert.com, loft insulation costs approximately £300 on average. In contrast, cavity wall insulation costs around £500 on average. It might therefore seem sensible to choose loft insulation over cavity wall insulation if you have a tight budget.

However, cavity wall insulation can save you more money than loft insulation in the long run. According to MoneySavingExpert, the difference is relatively small: it claims that cavity wall insulation can help you save just £10 per year more than loft insulation. However, other sources suggest that cavity wall insulation can save considerably more than this. The magazine ‘Which?’ asserts that cavity wall insulation can pay for itself in as little as nine months. In contrast, it suggests that loft insulation can take as long as two years to pay for itself. Both of our sources agree, however, that cavity wall insulation is more effective than loft insulation at saving you money on your energy bills. It is therefore a wiser long-term investment than loft insulation.

As you can see, both types of insulation have their advantages. But which type should you choose? The answer to that question depends on your situation. If you intend to live in your current home for a long period of time, it’s worth investing in cavity wall insulation (despite its relatively high cost), as it will save you considerably more money in the long run. If, however, you just need something that will help you save money for the next few years (and which doesn’t cost too much to install), loft insulation may be the solution for you.