Conservatory insulation, why should you care about ‘U’ values?

We often talk about how warm and comfortable a conservatory can be, but when it comes down to it, how do we quantify that? The answer lies in U-values.

The U-Value is a measurement of how energy efficient the spaces in your home are. They’ll be different for each room, including your conservatory.

I know what you’re thinking, “This doesn’t sound very interesting”, but trust us, knowing more about U-values could make sure you get value for money.

As a trained renewable energy engineer, our director Miles spends lots of time on calculating the U-value of the conservatories we work on. Both those we build and the ones where we improve the conservatory insulation and roof.

By calculating the wattage required to heat the space, and how much of that heat will be lost, we can be sure that we’re recommending the right solution to a customer.

When U-values matter, and when they don’t

By totting up all the materials used in a particular space, we can calculate the U-value. Each material will, for a given thickness and area, give us a value. So once each material is accounted for, we can use some fancy maths (if maths is your thing, you can see the exact calculations here) to get the final U-value, which will be in the form of 0.343 W/m²K. This means for every degree in temperature difference between the outside and the inside, 0.343 Watts of heat will move through that square meter.

The lower that number the more heat efficient the space, as it means less heat is needed to keep the space warm. So, U-values do matter.

However, they are not the be-all and end-all. Because U-values are numerical they make great headlines for marketing purposes. Companies who sell conservatory roofs are liable to shout various U-numbers as being “more” energy-efficient than their competitors. Pushy salespeople will then ensure you pay a premium for these low U-numbers.

However, low U-numbers in a conservatory roof only tells part of the story. When the heat hits the roof and is turned back into the room, what other surfaces will it hit? Brick? Glass? Plaster? Aluminium? Remember it’s the U-value of the whole conservatory that is important here, not just the conservatory insulation and roof. Glass, a pretty common material in a conservatory, remains one of the biggest causes of heat loss.

We often see customers paying high sums for lower U-values, because they were told this is the most important factor for a particular insulated conservatory roofing product or conservatory system.

However, as one of the most experienced companies in the UK conservatory sector, we know that you can make a conservatory comfortable all year round simply by looking at the whole picture and working to comfort levels, not U-values.

It’s worth noting that building control standards will specify allowable U-values. Many of the U-values cited by companies that use them in their marketing are far lower than required. This means you’ll be paying for something unlikely to make any practical difference to your heating bill or comfort level. All Seasons Roof in Dorset has a range of products that will ensure your conservatory is comfortable all year round while being economical to keep warm. If you do need to meet a particular building standard, we can help with that too. While we are accredited installers for products with marketing leading U-values, we keep the conversation about your comfort. Do get in touch if you’d like to talk about making your conservatory the perfect place you always dreamed of.