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Should I install more wall insulation?

If you want to make your home warmer and more energy efficient, one of the best solutions is to ensure the property is properly insulated. But once your home has the minimum amount of insulation recommended, is it worth adding more?

Types of insulation

For most modern houses, cavity wall insulation is the most appropriate option for the walls. Most houses constructed after 1920 have a gap between the internal and external wall. According to the Energy Saving Trust, filing this cavity with insulation can save a typical three-bedroom semi-detached house around £140 a year.

Consumer group Which? says that unfilled cavity walls could be responsible for as much as 35 per cent of heat lost from the home. It adds that the cost of installing cavity wall insulation is around £500, meaning that the expense is paid off in just a few years.

Older homes may have solid walls. These are harder to insulate, as the insulation must be applied to the wall, either on the inside of the property or the outside. However, just like with cavity wall insulation, the expense of solid wall insulation is made up by the savings on your energy bills within a short time.

Is more better?

Once your home is fitted out with the recommended level of thermal wall insulation, you should notice a dramatic improvement in its energy efficiency. The property should be easier to keep warm in the winter and your winter fuel bills should drop. Living in a warm home can also have a positive impact on your overall health and wellbeing.

With so many benefits to thermal insulation, it can be easy to assume that more is better. Maybe you could add some additional thermal wall insulation and make your home even cosier?

Well, actually, it seems that increasing your insulation beyond the recommended levels will only have a small impact.

Brian Horne, domestic energy expert at the Energy Saving Trust, told the Telegraph: "Once cavity wall insulation is fitted, although it is technically possible to add further external or internal wall insulation, this would be expensive and save very little in energy costs."

So, what can you do instead? Mr Horne suggests considering other energy-saving measures, such as loft insulation.

Loft insulation

According to Mr Horne, "After installing cavity wall insulation, there are other energy efficiency measures that the homeowner could look to install. These mainly include lower-cost measures such as topping up the insulation in the loft."

Loft insulation keeps heat from escaping out of the roof and should be at least 270 mm thick. If you're not sure about the thickness of your loft insulation, it's worth checking, as recommendations have changed in recent years.

There are many different types of loft insulation available. One of the most common products is the loose-lay material, which comes in rolls and is simply placed between the ceiling joists. However, if you plan to use your loft for storage or living space, you'll need to consider other options, such as solid insulation panels.

Mr Horne also suggests other energy-saving measures like installing draught excluders in doors and windows, filling in gaps around the floor and upgrading your boiler for a more energy-efficient model.