The door to Juan Botero's apartment in Houston, Texas, is wooden with an elegant walnut-like finish.

But, for Halloween, he planned a dramatic change. "I'm going to paint my door orange," Mr Botero, founder and chief executive of Glasst in Colombia, told the BBC last month. He also kept his promise.

However, the move isn't as drastic as it sounds. Mr. Botero's company is an "innovation company" that designs the paint to be removable - once dry, you can peel it off like plastic wrap. If it works as expected, it shouldn't leave any marks or residue.

Mr. Botero came up with the idea for the product, called Unpaint, about five years ago, and initially, his investors weren't enthusiastic. "They said I was crazy," he recalled. Still, he insists: “People are looking for customization in their lives.”

Glasst is just one of many companies claiming that house paint can do more than just look good. Manufacturers promise that a variety of products now on the market can save you money, keep you comfortable during a heat wave, or change your relationship with the walls of your home. But is it all too good to be true?

Unpaint will launch in the United States this November, and Mr. Botero believes there is a market for the product. He thinks it will appeal to people who live in rentals because they can't permanently change their decor.

Glaste predictably declined to reveal details of how it makes the coating, but Mr. Botero said it is a resin derived from renewable resources. I asked him if he meant trees, and he confirmed.

Strippable paint for car bodies already exists, but getting the product to work reliably on softer home interiors is more challenging.

Mr Botero said there is a risk of damaging the existing underlying paint when you finally remove Unpaint from the wall, but that won't happen if the permanent paint underneath is in good condition.

It does have an odd texture: "A bit like rubber," Mr. Botero said. Plus, it scratches easier than water-based lotions.

Bringing a product to market is not easy. Two years ago, Glasst posted a video about the paint on YouTube, but the launch was delayed until this year "to align with the right funding and resources needed," Mr. Botero said.

He mentioned that Glasst is working on other coatings with unusual properties, including "Thermglasst," an insulating resin that will be launched next year. Mr Botero claims less than 1mm of coating can provide the same insulation as 40mm foam.

There has been no independent verification of this claim, but there are a range of insulating coatings on the market that promise to cut your heating bills, and to be fair, they don't always perform well in scientific assessments.

In 2019, Richard Fitton of the University of Salford and colleagues Publish a paper They investigated the efficacy of six thermal paints on the market in the UK at the time. In short, they found that claims that such coatings could reduce heating bills by as much as 20 or 25 percent were impossible to substantiate.

First, the researchers coated the panels with paint so they could measure the coating's thermal resistance, or insulation value. The team then calculated the expected reduction in heating costs after applying these paints to the interior of a typical Victorian townhouse.

The maximum cost savings measured was only 2.9%, and given the price of the paint in question, at 2019 prices, homeowners may have to wait centuries or even millennia to recoup the cost of renovations: reduced heating costs.

"If someone brought me a paint that would save 25 per cent on my energy bill, it would be on my wall at the weekend," Professor Fitton said. He added that he is currently writing a follow-up paper to the 2019 study and would also be open to testing Thermglasst or any other insulating coating in the future.

Paint that helps keep your home cooler may be more effective. For years, researchers have been working to increase the reflectivity of exterior wall or roof coatings because this can help buildings stay cooler on hot, sunny days. This type of weather is becoming more common due to climate change.

This principle is as old as the hills – think of the white houses of the Mediterranean. But this effect can be enhanced by paint designed to be significantly more reflective than standard white paint. Hong Kong-based i2Cool is one of several companies currently selling such products.

In their case, the paint contains tiny nanoparticles and was inspired by extremely reflective objects Saharan Silver Ant – Must deal with the baking sun naturally.

CEO and co-founder Martin Zhu said the paint produced by i2Cool was tested on the roof of a shopping mall in Hong Kong, but only in one of its two buildings to see if it had a noticeable effect. Reduce building air conditioning (AC) operating costs.

"We use power meters to measure the energy consumption of AC systems," Dr. Zhu said. He added that the running costs of air conditioning in the repainted buildings dropped by 40%.

Dr. Zhu, who started working on the paint when he was a PhD student, mentioned that an early version made around 2017 contained silver, which made it very expensive—more than $100,000 just to cover a small area. After years of development, coverage now costs about $10 per square meter. Now it's also available in a variety of light colors, including grey, yellow and green.

The researchers note that highly reflective coatings used in passive cooling applications need to be resistant to dirt and stains to avoid a decrease in their effectiveness over time. Glare from ultra-reflective roofs has the potential to heat up nearby darker structures, 2020 Dissertation Proposals.

Dr. Zhu said i2Cool's paints do not contain heavy metals and use water-based emulsions, which are not biodegradable but can be recycled.

The company's latest major project is the Dubai Mall. The roof of this huge building complex—— The world's largest shopping mall by total area – will eventually be completely painted. So far, a 1,000-square-meter section has been completed.

Dr. Zhu said that although it has not yet been launched in Europe, this may change. "We are in discussions with some dealers in the UK," he said.