As a result of a record increase in global gas prices, the energy price cap has risen by 54% from the 1st April 2022 for approximately 22 million consumers. With average household price increases of between £693-708 per annum (and the global impact of our consumption), the importance of thermal efficiency is at the forefront of homeowners’ minds.

Amid the uncertainty of rising costs and consideration of our individual carbon footprints, homeowners are seeking to reduce their financial and environmental impact through a reduction of their energy usage. In recent months, we have seen increased interest in the energy efficiency of the homes that we are surveying so we thought it would be helpful to put together a Blog to address this pertinent issue.

We should start by saying that if you are unsure about the energy efficiency of your property, you can view your home's (or the home that you are looking to purchase) Energy Performance Certificate (EPC) at https://www.gov.uk/find-energy-certificate. The EPC will provide you with a rating for the current efficiency of the subject property along with suggestions to improve its energy efficiency. You will also see illustrative costs for the potential energy improvement works as well as likely savings.

Putting some of the 'big and expensive players' in home energy efficiency aside (e.g. solar panels, secondary heating sources), many of the most effective ways to improve thermal efficiency are less expensive and more attainable than we may think. We have explored a few of these options and have outlined them below:

1. Improve your insulation.

The average property allows approximately ⅓ of your heat to escape via its walls, and ¼ via the roof structures without proper insulation.

Cavity wall insulation is one of the simplest and most cost-effective forms of insulation. By increasing the energy efficiency of your home, cavity wall insulation can reduce heat loss and carbon footprint and can make the home warmer and cheaper to heat. Well fitted cavity wall insulation is estimated by The Energy Saving Trust to save an average of £137 per year (dependent upon the type of dwelling). Installation will cost approximately £200 per two storey wall, so a 3 bed terraced property could cost as little as £400 and would save approximately £185 per year (based on November 2021’s prices).

It should be highlighted that if moisture penetrates cavity insulation and bridges the inner leaf of the wall, its ability to keep your home warm will diminish. In addition, this can also lead to ‘cold patches’ in the home, where condensation may form on the inside of the property.

If your property was built prior to the 1920s, your walls are likely to be of solid construction and therefore unsuitable for cavity wall insulation. Insulation can still be provided, however, the installation costs are greater, at roughly £10,000-£14,000 for an average three bedroom semi detached house. That said, energy savings are increased at approximately £390 a year for the same property.

Internal insulation is the less expensive option of the two methods for older properties, however, it should be noted that there will be a small loss of internal space as a result of the installation method. This is because the introduction of internal insulation will involve removing the skirting boards, window sills, electric sockets, phone points, radiators and curtain rails from every external facing wall, before attaching rigid insulation boards to the wall.

External insulation is less disruptive as the works are all carried out to the outer face of the property. This method can also improve the external appearance of a dwelling.

Loft insulation is another cost effective method of reducing energy costs as it is estimated that approximately ¼ of heat is lost via the roof structure. Well fitted loft insulation is estimated by The Energy Saving Trust to save an average of £150 per year and can increase the value of a home by up to 16%. There are a number of different methods of insulation available and at a range of costs. For example, insulation of 270mm would cost approximately £300 in a semi detached house, with a saving of £165 per year when compared to an uninsulated space. Upgrading the same property from insulation of 120mm to 270mm would cost approximately £275 and save £15 per annum (based upon fuel prices as of November 2021). Whilst you may be tempted to install loft insulation yourself, we recommend that a professional insulation company is engaged to ensure the best method of insulation is used whilst adequate ventilation for the roof structures is provided. Poorly installed insulation can lead to condensation within the roof structure and, over time, potential degradation of the supporting timbers.

2. Eliminate draughts.

Draft proofing around the windows and doors of a standard semi-detached house can save approximately £45 a year, whilst an unused chimney can also be draft proofed and save around £65 per year. This method yields a good return when balanced against the cost of approximately £225 for the draft proofing of an entire standard semi detached house. As before, it is worth having this carried out by a professional as blocking up ventilation to an open fire or flue may pose a risk to health and/or lead to damp penetration to your property.

3. Update your windows and doors.

Double or triple glazing your property can save approximately £145 or £175 per year respectively. Upgrading glazing is a higher cost option and will require installation through a reputable company carried out within the requirements of Building Regulations (evidenced through FENSA certification). Leasehold buildings, listed buildings and those in conservation areas will also require relevant consents to be sought prior to carrying out the works. Typically, in these cases, you will likely be required to install fittings that are in keeping with the surrounding properties or those which are in keeping with the style of building.

4. Insulate tanks, pipes and radiators.

You can insulate your hot water tank easily with a cylinder jacket of at least 80mm thickness. In addition, foam piping insulation can be provided to hot water pipes. These items can easily be purchased for under £20 from a DIY store and fitted according to the instructions supplied. These simple and inexpensive measures will keep your hot water warmer for longer, thus reducing the reheating requirements. Such simple measures will reduce the annual bill of an average semi detached house when compared to a similar property with an uninsulated tank by £145 (based on prices as of April 2022).

Another simple measure is to add reflective panels behind radiators which are affixed to external walls. These types of panel will bounce heat back into the room instead of letting it escape via the external wall (of particular use with uninsulated solid walls).

5. Insulate Floors.

The cost of floor insulation for an average semi detached house could be between £1,300 and £2,700 and would save an average of £70 per annum. Solid floors can also be insulated, however, the cost is considerably higher. It should be highlighted that properties with suspended timber floors require the floor structure to be adequately ventilated in order to avoid the degradation of the timber due to humidity gathering within the void beneath. As such, external sub-floor vents to a property must not be sealed! It is possible to insulate these areas but we would recommend that this is carried out by an experienced professional to ensure the safety of the timber structure of the building.

Following on from the above, it is worth noting that sealing a property brings its own challenges, as adequate ventilation must be provided to ensure that humidity damage does not occur. If humidity is allowed to persist, over time, it can cause damage to a property and/or its structure. In order to assist in ventilating a property, humidity activated ventilation fans are recommended in areas of high humidity such as bathrooms, shower rooms and kitchens.

It should also be highlighted that when employing professionals to undertake works to your property, we always recommend that you carry out your own due diligence by meeting with the contractors and checking at least two of their references.

At Calsurv we are happy to comment on thermal efficiency and energy saving measures within our Home Survey reports. We will also review the methods seen in a property we inspect, comment on their effectiveness and make recommendations for improvements as required.

To summarise, many of the less expensive methods outlined above can make a big difference to the energy performance of a property. Whether buying, selling or staying put, efforts to improve your rating can maximise your savings and selling potential (whether long or short term).

Further information can be found at

https://www.simpleenergyadvice.org.uk/

https://energysavingtrust.org.uk/energy-at-home/reducing-home-heat-loss/