Could heat from your loft be putting your family at risk?

Could your loft be putting your family at risk?

  • Our Country can sometimes bask in prolonged summer heatwaves, such as the the record breaking summers of 1976 and 2013.
  • The Met Office frequently issue a Level 3 Heatwave Warnings during such spells of hot weather and in 2013 MPs called for the Countries wilting workforce to be sent home should temperatures continue to exceed 30.C indoors as part of new proposals.
  • The level three Heatwave Warning is issued when temperatures are considered to be dangerous for the very old or young who bodies have difficulty is regulating temperature and who are prone to dehydration and even death.
  • With 30C considered to be the critical level for health, could a poorly insulated loft be putting your life at risk?
  • As the Countries Rail Tracks buckle under the intense heat of the Sun and Tarmac on our roads starts to melt, take a moment to think about the effect the Sun is having on your BISF Home and the safety of your family.

Good levels of insulation in your home serve to keep your property warmer in Winter and cooler in the Summer. We are all used to turning up the thermostat, or lighting the fire as temperatures plunge but the majority of UK households have no facilities to cool the property down during the Summer months, apart from the odd fan or two.

It is no secret that non-improved BISF Houses are amongst some of the most poorly insulated properties in the UK but they are far from being alone in this respect. Around 30% of UK houses have single brick walls or walls that are considered hard to treat using traditional insulation methods such as cavity wall insulation.

What makes the BISF House stand out during times of excessive heat is the fact that the majority of these building were constructed using pressed steel panels to the upper floor level, along with corrugated steel roofing sheets, some of which were fitted as an alternative to asbestos sheeting and others being more modern day additions such as Decra Roof Tiles or Britmet Roofing Systems.

Steel by its very nature conducts and retains heat very well. As the searing rays of the sun hit these panels, they absorb much of the heat which can then be retained & transferred inside the building long after the sun has set. Whilst there is probably very little that you can do do stop this heat radiating in through the walls without undertaking extensive building work, you can help to stop the heat radiating down from the loft space and overheating your bedrooms by simply ensuring that you have adequate loft insulation fitted.

summer insulation

A simple indicator to determine if you do indeed have adequate insulation, will be the the temperature of your bedrooms during the evening. The loft space temperature during hot sunny spells can reach dangerously high levels.

We wanted to know exactly what those temperature levels were on a typical sunny day in the Midlands. In order to do this we chose a typical BISF property that had been fitted with a replacement Decratile steel roof. The loft in this property is very well insulated with two layers of thick 200mm mineral wool loft insulation and the upper floor steel sheeting covered in white UPVC cladding panels.

We used a simple digital thermometer incorporated into a digital clock/weather station reader that can be purchased from the High Street.

We placed the thermometer inside the loft on a cardboard box at a height of around 3ft from the inner Apex. Outside the weather was bright but slightly hazy with only a few clouds in the sky. The time was 14.00hrs and the date was today, the 17th of July 2012. To our surprise the temperature in the loft space recorded 44.6C or 112.28F, whilst the temperature in the bedroom below recorded a comfortable 25.9C or almost 20C less than the loft space.


We conducted the exact same test in the adjoining property that had been fitted with very poor shredded fibre insulation at around 3cm in thickness. This property also had a Decratile replacement roof with no upper cladding apart from the original steel sheets. The temperature in this loft space recorded a slightly lower 44.0C which was most probably due to the dissipation of heat into the poorly insulated space below which came as no surprise. What did surprise us though was the fact that the 1st floor bedrooms  both measured a very uncomfortable 31.0C, a full 5.1C higher than the insulated property. 31.0C is a full 1.0C higher than the cut off temperature recommended by MPs in which workers should be sent home from the workplace as currently there are no laws stating a maximum safe temperature for the workplace.

This temperature variation is more than enough to feel very uncomfortable and even dangerous for the very young or elderly who have greater difficulty in regulating body heat.

In particular, very hot weather can make heart and breathing problems worse.

“There is considerable evidence that heatwaves are dangerous and can kill,” says Graham Bickler of the Health Protection Agency. “In the 2003 heatwave there were 2,000 to 3,000 excess deaths (more than usual) in England. Across Europe, there were round 30,000 excess deaths.”

We must stress that this test has no scientific merit but in our test case situation, it outlined very clearly the safety and comfort benefits of installing a good level of insulation into your loft space, that will serve to not only keep you warmer in Winter and cooler in the Summer but it could also save a vulnerable family members life.

It is also a time to consider what you have stored in your loft as many electrical items will not appreciate being stored in such stifling conditions. Remember also that aerosol cans and perfume bottles could well explode if stored in high temperature conditions.