Why do we insulate our houses? – Can I Just Ask? – Episode 3

Why Do We Insulate Buildings?

It might seem like a basic question, but it’s one that’s worth revisiting. Why do we insulate our homes and buildings? While many clients come to us already committed to insulation, the full scope of its benefits often goes unspoken. At its core, insulation isn’t just about energy—it’s about creating healthier, more comfortable, and more sustainable spaces.

If you’d rather hear Andy and Chris talk through the ideas in this article, you can watch Episode 2 of Can I Just Ask? below. 👇

Energy Efficiency and Carbon Reduction

The most obvious and widely accepted reason for insulating is to improve energy efficiency. Well-insulated buildings require less energy to heat and cool, which not only reduces running costs but also significantly lowers carbon emissions. In an era of climate consciousness, this is no small thing. By minimising our energy consumption, we reduce our dependence on fossil fuels and make a tangible contribution to the fight against climate change.

Comfort and Indoor Climate

That said, energy savings are just one part of the equation. Perhaps more immediately noticeable is the improvement in comfort that insulation brings. We now spend the vast majority of our time indoors, whether at home or at work. The quality of that indoor environment has a profound effect on our health and wellbeing.

Insulation helps create stable indoor temperatures by reducing heat loss in winter and heat gain in summer. But it’s not just about temperature. Insulation also plays a critical role in managing internal moisture loads—a factor that’s often underestimated.

Moisture Management and Building Health

Modern living generates a lot of indoor moisture: cooking, washing, breathing, even drying clothes indoors. In older buildings that weren’t originally designed to handle this kind of humidity, that moisture can become a serious issue.

Poorly insulated walls tend to have colder internal surfaces. When warm, moisture-laden air hits those cold surfaces, condensation forms. This creates an ideal breeding ground for mould and bacteria, which not only damages the building fabric but also degrades indoor air quality.

By adding insulation, we can raise the internal surface temperature of walls, significantly reducing the likelihood of condensation and its associated problems. Combined with effective ventilation, insulation is a vital part of maintaining a healthy indoor climate.

The Hidden Cost of Cold Surfaces

Cold, damp surfaces aren’t just a maintenance issue; they can impact our health. Mould spores and bacteria thrive in high humidity environments and can contribute to respiratory problems, allergies, and conditions like asthma. The perception of comfort is also affected by radiant temperature—that is, how warm or cold our surroundings feel, not just the air temperature. Insulated spaces feel warmer and more comfortable because the surfaces around us aren’t absorbing our body heat.

Insulation as a Systemic Solution

Ultimately, insulation isn’t a one-size-fits-all fix, but it is a foundational element in sustainable building design. Whether retrofitting a historic home or designing a new build, getting the insulation strategy right is crucial. It supports energy efficiency, reduces health risks, enhances comfort, and protects the building fabric over time.

So, while “Why do we insulate?” might not be the question we hear most often, it’s one of the most important ones to answer well.