The precise choice of material will depend on the climate zone where the building is located – the requirements for a location that gets very cold in winter will be rather different from a zone where it’s warm or hot year-round. ‘In the north, closed cell foam is primarily used. In the south or middle America, open cell can be very successful,’ Wells said.
Closed cell foam is also commonly used in areas prone to hurricanes or tornadoes. This type of foam attaches firmly to the roof of a house, preventing wind uplift. Although it is more expensive than open cell foam, it gives greater structural strength. ‘Another good place to use closed cell is in basements and crawl spaces because it provides a vapour barrier,’ he said. ‘Open cell should not be used anywhere that might get wet, and it will require a vapour barrier if it is used in colder climes.’ That vapour barrier is not needed with a closed cell foam.
Kramer said that more than half of the market is closed cell. ‘A lot of that is driven by climate zones and code changes relative to air filtration, which is becoming more of a focus,’ he said. There is a common misconception that homes can be too airtight, he believes, but there is a move towards constructing tighter structures. ‘With highly efficient and variable functional HVAC systems, this is going very well,’ he said. ‘This is the key – as long as there is sufficient air exchange, you cannot make a house too tight. It’s changing the way we construct.’
Building codes and installation
The way insulation products are used has an impact on performance – and installation cost. In contrast to spray foam, which is applied continuously, polyiso insulation is delivered to the construction site as boards. These need to be taped, caulked or sealed at the joints to give the air barrier that spray foam automatically provides. Polyiso foams have about the same R value per inch as a closed cell SPF; the value for PS is lower.
Early adopter Flaim set up Biofoam in 2005. This was a couple of years after she bought her own SPF rig. That move was prompted when, as a real estate agent, she started specifying building products for construction projects, and struggled to find a local contractor. At that time, SPF still wasn’t widely known.
‘People were intrigued, but homeowners weren’t asking for it – at the time they weren’t even asking what kind of insulation a property had,’ she said. ‘It was a way for us to differentiate our projects. We could say they had high-efficiency insulation as standard.’
It was years before SPF became standard practice for insulation. ‘The end customer always drives trends in homes, so if they are not asking for a feature, the builders will save money,’ she said. ‘But they started to offer it as an upgrade if the customer wanted to pay extra, and now in the majority of the quality builders, spray foam is standard now in my region.’
Driving future uptake
Building codes are likely to drive future increased uptake. In some areas, Wells said, codes are being adopted that include requirements for air exchange inside buildings. ‘As these codes get adopted in different locations, they will be more likely to use spray foam as otherwise they have a hard time meeting the codes with insulation that isn’t an air barrier.’
The opportunities for more widespread use are still there, Flaim said. ‘Rarely do you see a foam roof with a foam exterior wall, as well as in the waterproofing,’ she said. ‘One of my favourite ways of installing foam is on the exterior rather than the interior, and a lot of people don’t realise it’s a three-in-one product. And it’s always great to present a success story. No-one wants to be a guinea pig – they want to know where it’s been proven, with savings of money or time or energy costs.’
Flaim would like to see manufacturers interact more with architects and specifiers to speed up SPF’s adoption. ‘I would like to see more involvement in the design and build process, and more advocating for the benefits to the end-user for installing the product.’ she said.
The US SPFA carried out lifecycle assessments for SPF five years ago and has just updated them under ISO rules. Its published environmental product declarations (EPDs) are, essentially, condensed versions of the long Life Cycle Analysis (LCA) documents aimed at architects and specifiers trying to meet sustainable building programmes, such as LEED. While the SPF assessments are only applicable to the north American market, they give a good indication of how the product performs to users elsewhere.
SPFA’s Duncan explained that, overall, the environmental impact of SPF is not substantially different from other foamed plastics such as polyisocyanurate, polystyrene and expanded polystyrene. Compared to fibreglass, the positive difference is substantial -- the impact of the plastics is much higher. However, he said, it must be remembered that spray foam is not just insulation – it’s also an air barrier and can be water resistant. ‘It also adds to the strength of the structure,’ he said. ‘In many cases, a closed cell foam can reduce the amount of wood framing needed for a building. Those EPD results should be considered as a part of a whole building impact LCA.’
An architect should take all the materials used to evaluate the building’s environmental impact – including air barriers, vapour retardants and changes in the framing. ‘The EPDs [for different materials] really shouldn’t be compared directly, but should be integrated directly into the whole building’s LCA.’ So for a fair comparison with fibreglass, all the other materials that will be required to make fibreglass perform as well as SPF should also be included in that LCA.
The potential energy savings of using spray polyurethane foam are substantial. Wells said the saving depends on what is done and how big the building is, but he has seen projects where energy bills have been halved. ‘The savings can be very big,’ he said. ‘In the near-13 years we have been doing spray foam, I have never had someone telling me they wished they had not done it.’
It can be easier to get interest from people building a custom new home because one is talking to the end-user who will directly see the benefits to the energy bills. For commercial developments, whether they are for residential or business use, the developer is more likely to focus on the bottom line of how much construction will cost, and not the cost-in-use for the ultimate owner.
Wells believes that, unless a developer of commercial buildings understands the importance of saving energy and really cares about it, they will still simply look for the lowest cost. ‘If you are looking for the lowest cost, spray foam is not what you are going to be using,’ he said. ‘But we have contractors who do commercial work, who understand and exclusively use spray foam. Others aren’t interested in being a spray foam salesman and telling people why the cost of the units are higher and why they are better quality. That can make it a little tough, but this is starting to shift as well.’
Moving away from HFCs
The new, updated EPDs include foams made with the new HFO blowing agents such as Honeywell’s Solstice. There are substantial environmental benefits in making a switch to HFOs, Duncan said. ‘For the same closed-cell foam, we see a reduction of about 90% in terms of global warming potential compared to older closed-cell foams with HFC blowing agents.’
Much of the world is phasing out HFCs, but the planned phase-out in the US is not happening. This is because a court ruled in 2017 that the Environmental Protection Agency did not have the jurisdiction to force a change to fourth generation blowing agents. In contrast, the ban will be implemented north of the border in Canada at the beginning of 2021. ‘Many of our manufacturers have already prepared for the new HFO blowing agents, and several have released products where HFOs replace HFCs,’ Duncan said. ‘But manufacturers can continue to make foams with HFCs, and some have opted to do so because of the costs of bringing in new products.’
However, this is not the end for the HFC ban: several US states, including California, are writing regulations that will require HFC phase-out, regardless of the federal rules. ‘Manufacturers have realised this and are going ahead with HFO blowing agents,’ Duncan said. ‘We expect that with the new administration after 2020, things will change.’
Wells believes that the industry simply needs to use the newer blowing agents. He uses a product that is blown with Honeywell’s HFO product Solstice. ‘Being a good steward in the industry, you need to do the best you can,’ he said.
Flaim always tries to offer the most environmentally friendly option, but the owner is often only looking at price. ‘We do always try to push the new blowing agents, and advocate that this is what the industry is moving towards, but we are not the decision makers,’ she said.
The industry is moving fast, which can cause its own problems. ‘Sometimes we get specifications for products that don’t exist anymore,’ Flaim added. ‘That’s an opportunity to explain what is now available. If they are interested in the environment, and their client is interested in any kind of green certification accolade, they absolutely want to know about it. We always bring it forward as an exciting opportunity. You can either say it is greener but more expensive – or highlight all its great attributes.’
Training and education
Good training and experience among contractors is crucial. ‘Unfortunately, there are people out there who are not very professional about how they run their business. Even more unfortunately these get more press than all of the good contractors,’ Wells said. ‘But the industry is heading in the right direction. SPFA has a professional certification programme that has gained a lot of traction in the past couple of years. It is a fully comprehensive spray foam training programme, all the way from beginner installers up to project managers and expert sprayers.’
He added that social media is playing a part, as well. A closed Facebook group called Spray Foam Worldwide now has about 7,500 professional PU foam installers. It acts as a forum allowing contractors around the world to speak to each other and solve problems.
The industry is now stepping up to enforce training requirements, Kramer said; and he is a big believer in licensing. ‘Electricians have to be licensed in the US, so I don’t see why we wouldn’t require it as well,’ he said.
Wells said that education still represents a big challenge, all the way from installers to the code officials doing inspections. ‘The more education we can get out there, the more we will all benefit from this product that is far superior and can help people in a lot of ways.’
Keep on teaching
It is important industry continues to educate contractors and consumers about the value of the product, Kramer said. ‘The industry has come a long way in the past 25 years in terms of technology and safety. I think the biggest change is the continued evolution of quality and scale of contractors,’ he said. ‘There has been a consolidation at a national contractor level, again raising the stakes with the size of the companies that are participating.’
In the coming years, Kramer believes, there will be good, steady, continued growth. ‘I think everyone will catch up on HFO technology . It will be broadly accepted for closed cell foams,’ he said. ‘I also think there will continue to be innovation around spray foam. This could be better yield giving lower costs, new blowing agents, and other innovations that will help make the product more cost-effective and broadly accepted. We don’t see any major risk in disruption of the momentum, and the industry is becoming more sophisticated.' This is true 'in terms of consolidation at the distribution level, the contractor level and the manufacturing level. That is typically the sign of a maturing industry. The demand seems to be sustained – and sustainable going forward. We are very optimistic.’