The UK’s lockdown has seen us all spending more time at home. Naturally, this has led to significant changes to our lifestyle; some positive, others less so. At Switchee we have been thinking: with all of this extra time at home, what impact is it having on our homes?
With thousands of Switchee devices installed across the UK, from Hastings to Perth and Swansea to Norwich, we have been able to get unrivalled insight into how our new lifestyles are impacting the conditions in our homes. With its five sensors sending readings once every ten minutes, each Switchee device sends 720 data points per day and 262,800 each year. For a housing stock of 10,000 properties, this equates to 2.6 billion data points per year. And this is just from Switchee’s five sensors, it does not include the external weather and boiler firing data Switchee is also collecting.
In spending so much more time at home, many of us have been concerned about increases in our energy usage, and subsequently, our energy bills. During lockdown, we have worked closely with a number of housing providers to get free energy advice to residents who are concerned about rising energy and gas costs. Whilst Switchee does not track overall energy usage, it does track heating and boiler usage to help improve efficiency and monitor boiler performance. What our data shows is that despite more time being spent at home, heating and hot water has been used less than the equivalent time period last year. Why is this? Well, the simple answer is, because the weather has been so good.
For the sake of fair comparison, we are comparing the dates of the UK’s full lockdown in 2019 and 2020: 23rd March – 10th May.
The graph below compares the average daily weather temperature for each Switchee across the lockdown period in 2019 vs 2020. Each Switchee device gathers weather readings from its nearest weather station. So if in your part of the country it felt warmer than 16°C on 9th May this year, remember that this is a daily average across all Switchee devices - it will have been much cooler elsewhere in the UK. The graph clearly shows that the lockdown period in 2020 has been warmer than the corresponding period in 2019 – a difference of just over 1°C. The average temperature in 2019 was 8.76°C while in 2020 it was 9.78°C - a percentage increase of 11.6%.
This increase in weather temperature could be the leading factor in the significant reduction in boiler firing times over the lockdown period as displayed in the graph below. The average boiler firing time over this period in 2019 was 6h12m, in 2020 it was 3h02m – a 51% reduction. Of course, there are other reasons why people might be using their heating less this year compared to last year. It could be part of a concerted effort to reduce the use of heating on lockdown as financial pressures take their inevitable toll on many of us. Moreover, Switchee’s user nudges could be attributable to more conservative heating usage. You can read more about how Switchee is fighting fuel poverty in this white paper.
What we can conclusively say is that, unsurprisingly, as the weather temperature increases, the length of time we heat our homes reduces. The graphs below show the lockdown period in 2019 and 2020 and the boiler firing time is almost the exact inverse of the weather temperature in both years.
It has been a similar story with hot water settings. We have seen a 7.9% reduction in average hot water usage between 2019 and 2020, from 6h07m to 5h38m. Since hot water settings tend to remain largely constant throughout the year regardless of weather temperature, this reduction might again be indicative of people reducing their hot water usage in an effort to reduce gas bill costs.
With households at full capacity for more time during 2020’s lockdown period, homes are more exposed to moisture being generated by humans, thus leading to higher humidity in homes. The Institute of Specialist Surveyors and Engineers (ISSE) suggest that one person spending a day at home carrying out normal activities can produce 1.6kg of moisture. Multiply this by the average UK household of 2.4 people, this represents 3.84kg of moisture being added to a home. If we conservatively estimate that people are spending an extra 8 hours at home during lockdown when they would typically be at work, this equates to an additional 1.28kg (one third) of moisture being added to the home each day. This is not including the likely additional use of appliances that release moisture, such as showers and dryers.
Low and behold, our data shows an 23.5% increase in absolute humidity (AH) in the 2020 lockdown period. Here we use absolute humidity as it measures the moisture in the air regardless of temperature. What’s more, weather AH was 2% lower in 2020 than in 2019, taking the adjusted AH increase to 26.2%.
As has already been displayed, the weather temperature during the 2020 lockdown period has been greater than that in 2019. However, the weather relative humidity has been lower in 2020 than in 2019. Despite this, we have seen considerably greater average RH inside homes during the lockdown period in 2020 than in 2019 – 46.9% compared to 38.1%, a 23% increase. When adjusting for this year’s lower weather relative humidity, there is a 27% increase this year. The graph below compares the 2019 and 2020 average RH readings.
With all of this extra moisture building up homes, it begs the question: what does this mean for condensation, damp and mould?
It is difficult to say right now, however, it is widely accepted that more moisture is likely to accelerate mould growth. The rate of mould growth is dependent on a few other factors, namely temperature gradients. This is where relatively warm and moist air comes into contact with relatively cool surfaces, much like it does on a glass of cold water on a warm, humid day, causing a build-up of damp. This issue is usually exacerbated in the colder winter months when surfaces are cooler making it easier for moisture to condense. However, there is still a risk in the warmer spring/summer months. There is a temperature gradient during cooler night times that can lead to damp build-up. At Switchee we will be encouraging our clients to keep a close eye on the mould risk rating for each home. Read more about how technology is being used to reduce condensation, damp and mould in our white paper.
In summary, our data analysis shows that the worst effects of the COVID-19 lockdown on our household gas usage has been eased somewhat by the good weather in the UK over the past two months. This will hopefully go some way to cancelling out the increased energy costs many homes will be experiencing during lockdown. It does, however, pose the question – if UK quarantine measures extend past summer 2020 and into the colder months, how much will gas usage (and the subsequent bills) increase? With the UK set for its largest recession in a generation and with thousands of jobs expected to be lost, will more households be pushed into fuel poverty and forced to choose between eating and a warm home? Only time will tell.
Furthermore, as summer turns to winter, will the cooler weather and increased household occupancy encourage more condensation, damp and mould growth in homes? Again, time will tell, but the likelihood is that it will. To help prevent this, it is key that tenants are made aware of ways to prevent damp. Many housing providers offer this as a service and distribute leaflets guiding their customers on how to prevent damp and at Switchee we will be encouraging our clients to make use of our messaging feature to ensure that this advice gets through to tenants. At Switchee, it is our mission to ensure that our device is being used to improve the homes and lives of the people living in the five million homes managed by the UK’s housing associations and local authorities.