Do vines insulate your home?

With the energy and cost of living crisis on our minds, more people are considering creative ways to stay warm at a low cost this autumn and coming winter, while sparing the environment too.

And it appears insulating our homes with nature itself could be a possible method. Take Michael and Teresa Lye, a retired couple from Bromley, for example, who are using green energy to hopefully do just that.

After originally trying to tame the vines covering their house when they moved in in 1984, they're now happy to let the climbing plant grow, seeing the benefits.

"We think it acts as natural insulation," says Michael, 75. "The room is nice and warm," adds his wife Teresa. "Go in any of the rooms – it's warm. That's why we've got a fan in here. In the winter we are toasty."

The temperature inside has even prompted their daughter to ask if they have the heating on (which they don't).

But are vines really capable of insulating your home? And what about the structural damage they might cause?

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Watch: UK couple finds natural way to keep their home warm by covering their house in a climbing plant

Do vines insulate your home?

Describing plant-covered sections of buildings as 'living wall systems (LWS)', one study by the University of Plymouth found they can reduce the amount of heat lost through its structure by more than 30%.

To come to this conclusion, they used a pre-1970s building on campus to compare how two sections of its walls retained heat, including one fitted with an exterior LWS facade and the other left untouched.

The paper, with lead author Dr Matthew Fox, states: "Whilst this study is not representative of all situations and wall types, the findings suggest that adding a LWS to the façade of an uninsulated cavity masonry wall could be used to lower heat losses in addition to bringing many other benefits, such as increased biodiversity, sound absorption and reductions in air pollution."

A study conducted by the RHS and University of Reading found that ivy is the most effective plant cover for both cooling buildings and reducing humidity. Researchers discovered ivy helped to reduce the internal and external wall temperature by 7.2°C and 5.7°C respectively, more than Virginia creeper and climbing hydrangea. As well as keeping buildings cool in winter, it also helped to keep them less damp in winter.

Additionally, a Historic England 'Ivy on Walls' report also explains how a vine can help regulate building temperatures in different circumstances. "We now have strong evidence that ivy reduces... freeze-thaw, heating and cooling [a heat loss or gain] and wetting and drying [how moist it is]… through its regulation of the wall surface microclimate," it states.

"Ivy canopy does not need to be very thick to have such an effect, and the benefits seem to affect walls in many different climatic regions and in exposed as well as shaded positions."

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Can vines damage your home?

The Royal Horticultural Society (RHS) website provides information on the specific plants that could cause issues – and the varieties that are considered safe.

"Self-clinging climbers such as Boston ivy and Virginia creeper do not usually cause damage to wall surfaces, but common or English ivy supports itself by aerial roots and where these penetrate cracks or joints they may cause structural damage," the website states. "Sound masonry is unaffected."

It adds, "Where brickwork is sound, the main problem is to keep growth away from gutters and paint work."

Gardening expert Harry Bodell, who has over 10 years of gardening expertise in both commercial and residential settings, also gives an insight on whether different types of vines can be damaging.

"Non-clinging vines that rely on some kind of structure like a trellis for support help to keep the vines away from the building’s façade. These vines pose almost no threat to your home’s exterior as they don’t climb on their own," says Bodell of PriceYourJob.co.uk.

However, he adds, "Clinging vines with tendrils and aerial rootlets can pose a threat to buildings – particularly ones with sticky discs. If you have any deteriorating areas of your external walls such as gaps around the windows and doors or cracks in the masonry, this could cause a threat.

"Twining types of vines [climbs by its shoots] may have large stems that could sometimes be as thick as the limbs on trees. Woody twining vine types pose the most threat. These varieties can dislodge downpipes and guttering. They can also cause clogs in the gutter and may pose a threat to shingles and siding."

"Additionally," Bodell points out, "the weight of vines over time can make the roof of a building collapse and pull down power lines.

"If the vines are on the north side of a building, they may not get enough sun so the rainwater and dew may not dry off fully. This could cause a build-up of moisture that can lead to mould, rot and infestations of insects."

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While using vines to insulate your home could mean using the heating less and cutting energy costs, this would also help to reduce your carbon footprint and the harmful effects on the planet.

But of course, it's wise to weigh up the pros and cons for you and your home before you immediately start planting or stop chopping yours. If you do want to give it a go, see this RHS website page on how to plant a climber.