Top Ten Tips: How to Improve the Energy Efficiency of an Older Property

If you live in an older property, chances are there is something you can do to improve its energy efficiency. A home’s energy efficiency is defined as using less energy to perform the same task (i.e. heating and cooling.) This Top Ten Tips list has been created with Victorian through to early 1950s homes in mind. Cost estimations have been included, based on 3-4 bedroom semi-detached properties. However, many of these tips will also be of benefit to those living in properties constructed up until the early 2000s, before Part L of the Building Regulations – Conservation of Heat and Power – was first published.


    A whopping 35% of a home’s heat is lost through un-insulated walls. Internal insulation can be a costly option and has the undesirable outcome of reducing room size. A relatively cheap and effective option is to install thermal liner. This product is similar in appearance to wallpaper. Incredibly it improves the U value of your walls, claiming to achieve a 15% energy saving! Simply decorate and no one will know it is even there. Interested in learning more? Visit my product review of Wallrock Thermal Liner from when I installed this product in my home.

Estimated cost – £200-£350 per room, depending on room size



    External solid walls may be insulated using an external insulated cladding system, however this can be expensive and may not always be an option. Cladding may greatly change the character of a house and as a result, may not be granted planning permission. For an eco-friendly alternative that has the potential to save you up to 15% on your energy bills, it is worth considering cork render. This innovative product is breathable, waterproof, will not crack, and has up to 40% improved thermal resistance compared to traditional renders. Other benefits include acoustic insulation and achieves Euro Class B fire resistance, as well as being made from 100% natural material. For more information, visit CorkSol or ecoCORK.

Estimated cost – £8,000-£15,000 for the home entire.



    This form of insulation is only suited to double brick skinned properties, typically constructed from the 1930s onwards. The process involves inviting a registered installer to drill small holes into your perimeter walls and inject insulating materials, such as mineral wool, polystyrene beads or polyurethane foam into the cavity. This is a relatively quick an easy process and it is possible to make back the installation cost in under 5 years. Please note that this method does not suit all properties with cavity walls. It is recommended that a borescope investigation is carried out first to determine cavity thickness (minimum 50mm), and confirm the cavity is free from builder’s debris. Cavity wall insulation should not be installed in homes in exposed conditions at risk from high winds and driven rain.

 Estimated cost – £400-£600 for the home entire.



    A relatively inexpensive and easy solution that reaps tangible benefits. An average property loses 25% of heat energy through air leaks around windows and doors. The ideal solution is to replace the windows and doors with new tightly fitting double glazed units, however this is sometimes not an option due to planning or budget constraints. Where this is the case, it is best to opt for hanging thick curtains, preferably thermal curtains which can be purchased from major retailers such as Dunelm, John Lewis and the Range. Another option is to DIY your own Kume curtains which are more alike to insulating blinds. I love the DIY advice provided by (Thanks guys!)

Estimated cost – £25-£150 per set of thermal curtains.  £15-£25 (approx.) for DIY Kume depending on fabric used.



    If your home still has single glazed windows, where possible, it is worth investing in double glazed units throughout. This will add value to your home and save you approximately £100 per year in energy bills. Unfortunately, new double glazing does not come cheap and may be an unaffordable option. If this is the case, in addition to item 4 above, we recommend draught proofing to the perimeter of all windows and doors, or even installing magnetic secondary glazing (see Magneglaze for details) which is both economical and effective.

 Estimated cost – Between £5,000-£15,000 for new windows depending on the size of your home and the quality of the product. 


  1. ROOF 

    25% of the heat energy produced by your boiler could be lost through the roof if uninsulated or where insulation is old and of insufficient depth. We recommend that loft insulation is installed between the joists to a depth of 270mm. Natural fibre insulation products should be used, such as Thermafleece sheep’s wool insulation and Pavatex wood fibre insulation.

Estimated cost – £150-£400 initial outlay, however this saving will be recouped within 2-3 years of installation.



    Older homes are often purchased by people with a love of period features, such as high ceilings and ornate fireplaces. In many rooms, fire places may only be retained as a decorative feature, however these can cost homeowners hundreds of pounds each year if the chimney has not been capped or blocked. To maintain the option of using the fireplace in the future, we recommend installing a Chimney Sheep. The product is made from 100% Herdwick wool and as well as improving the thermal efficiency of your home, will prevent wildlife and debris falling in, stops wind noise as well as saving you money on your energy bills.

Estimated cost – £20-£70 depending on the size of your chimney.



    Ground bearing concrete floors were introduced in the early 1930s. They  increased in popularity in the 1950s following the war when limitations were placed on importing timber. Early concrete floors contained little or no insulation, it is however possible to upgrade your existing slab. Strip back all existing floor coverings and add rigid insulation, (such as EcoTherm thin rigid floor insulation boards,) and top with a vapour control membrane and your chosen floor covering. A negative side-effect of insulating in this way is the need to remove all skirtings and radiators to allow for increased floor level, and doors will also need to be shortened. A raised floor level would also likely create unequal step heights which do not achieve building regulation requirements. For this reason, upgrading concrete slab insulation may be best suited to those living in bungalows.

Estimated cost: Between £2,000-£10,000 depending on the size of your home and the number of associated adjustments required.


    For older properties with suspended timber floors, much thermal energy is lost due to the passive ventilation circulating cool air below the floor boards. Whilst this design prevents the timbers from rotting, this cool air may make your home difficult to heat. To resolve this issue, it is recommended to retrofit a thermally efficient insulation system beneath the floorboards. Best practice involves installing a breather membrane up and over the top of the joists to create a support for a natural, breathable high-performance insulation such as Thermo Jute 100 or GUTEX Thermoflex. Finish with an airtight membrane fixed over the insulation and joists, followed by replacement of the floorboards and floor finish.

Estimated cost – Between £500-£1,500 depending on the condition of your existing floorboards.



    Your old boiler may still be in good working order, however if it is more than 10 years old, it is likely to be an inefficient gas guzzler! But how can you tell? The first step is to find out the energy rating of your boiler. Boilers are rated A-G (with A most energy efficient.) If your boiler is rated D-G, or has no rating at all, investing in a new boiler will both substantially reduce your home’s carbon footprint, whilst also substantially reducing your energy bills in the long term.

Estimated cost – £2,000-£4,500 depending on boiler type and quality.

Note: If your home is for life and you want to invest in the best, consider a Hydrogen Fuel Cell Boiler. These boilers use natural gas to produce both heat and electricity whilst expelling zero emissions other than water vapour. Sounds interesting? Visit my blog page all about the Viessmann Vitovalor to learn more.