by Liz White, editor
A lack of emphasis on insulation at the recent Ecobuild show in London has already been noted in this issue’s comment: insulation experts UTI spoke to at the event, at Earl’s Court, 3-5 March, had a good idea of the background to this.
“A big problem for the whole insulation market is that you come across ‘Eco Bling’,” said Kingspan Insulation Ltd’s marketing manager, Peter Morgan. This effect is what leads people to put a costly wind turbine or expensive solar panels on their roof, “without bothering to insulate and make that building perform as best as it can.” This can have various repercussions, said Morgan. First, “They may have to buy a renewable resource that’s overspecified — because you failed to prevent heat loss.” Also, “Potentially, you are producing valuable energy to put into a leaky underperforming building structure,” he added.
“That’s bonkers,” Morgan said.
But of course the other aspect of any sort of insulation, part of its value if you like, is that it’s “invisible and passive,” the Kingspan representative commented. This means that, “It just sits there doing its job, it’s not sexy, it just works,” he said. People would rather spend their money on a new kitchen — something visible that does raise the property value, Morgan said.
Kingspan was busy promoting its phenolic insulation at Ecobuild and Morgan was relaxed about competition in insulation materials: “Every insulation has its plus side.” And there is a recognition issue for foam insulation: “If you look at the average consumer, insulation is the stuff that’s rolled out in their attics, that’s people’s perception of insulation,” Morgan said.
“When people think, ‘I’m trying to keep my gas and oil bills down for heating. What can I use,’ that’s what they think of,” he continued.
A similar point came from Mohamed Hussein, market development manager for spray foam with BASF in the UK. In talking to manufacturers of timber-framed structures at Ecobuild, and looking around the show, he realised that, “people identify mineral wool with insulation. They’ve all seen it in their lofts, so they think that’s an accepted material, and a way of building.” Morgan noted that the sector is awaiting the next change to the UK’s building regulations — Part L — which deals with thermal performance.
This was still in consultation at the time of Ecobuild in March, with discussion focussed on possible tightening of the specifications for U values (heat transfer coefficient)
Hussein said that, at the moment, the UK’s limit for airtightness of buildings is 10 m3/h/m.2 “They’re looking to lower that to 8 m3/h/m2.” That will benefit spray foam, where “airtightness can be guaranteed,” he feels.
Europe’s values are tighter, Hussein commented, saying Germany is for example now looking at a limit of about 4 m3/h/m2.
Back to basis with insulation
Discussing the lack of focus on insulation at Ecobuild, Hussein said that, with his background as structural engineer, he feels “We jump too far ahead and forget the basics of how to achieve a well insulated structure to start with, and make it airtight.” And he said that there are also many misunderstandings about airtightness. “People come to me and say there are health issues for example.” Then he has to point out that, “We’re not talking about not ventilating. We’re talking about controlling airtightness so that we can then decide how and when to ventilate — and at the same time prevent heat loss.” “With insulation, airtightness will save energy, especially with refurbishment, where you have old plumber’s holes and electrical outlets which are not properly sealed, giving gaps in the building fabric,” Hussein said.
And he noted that the polymer foam sector must keep on “educating the specifiers, continuing training, offering case studies and even pilot projects, to demonstrate what can be achieved.” One thing he noted at Ecobuild is that “people are frightened of chemicals.” Kingspan’s Morgan also pointed out that, while people have to provide energy certificates for domestic properties, insulating, “does not add value to your property currently. It’s as simple as that.” It cuts energy bills, but won’t allow you to sell the property for a higher sum.
But when energy prices go up, then the pressure for better insulation rises also, he noted. This is why regulations are essential to get people to do the right thing and insulate, Morgan agreed.
Embodied energy (not) a key issue
For PIR (polyisocyanurate) and phenolic foams, “everyone decries their embodied energy,” Morgan said. But “for sheep’s wool and other fibre materials — which have their place — what people forget is that ... all the other thicknesses – of timber, and concrete have to increase also.
... That extra material increases the embodied energy in the building fabric,” he explained.
Discussing who needs persuading to use insulation, Morgan noted that architects are already convinced: insulation is mandatory.
And he made a similar point to that of Hussein: “Where people do need convincing ...
is if you are a consumer and have your rewiring done, or re-roofing or re-rendering ...
[you should] insulate at the same time and make the best use of that disruption,” he stressed.” And as regulations increase, and better U values are needed — “ then the plastic foams start to have real advantages, simply in terms of being able to do this without increasing the size of the building envelope/footprint massively,” the Kingspan executive continued.
While critics might say that as an insulation supplier, Kingspan “would say insulate first,” Morgan said, “It is the most sensible option.” For example, “It’s not influenced by behaviour in a building, it’s not going to break, you don’t have to understand how it works — which can be important, especially if you’re elderly or infirm or English is not your first language,” which is increasingly common in Kingspan’s customers, Morgan said.
Aerogels on the way
At Ecobuild, EcoTherm, which makes rigid insulation boards using PIR foam in the UK and the Netherlands, launched an aerogel-based insulation, Spaceline, noting that “a few other companies were launching similar materials.” This silica-gel-based material is offered in very thin sheets, and has a “fantastic” insulation (U value) of 0.13 W/m2.K, said a spokesperson. “It comes on a roll, you just roll it out and can plaster over it,” she added.
“If you have a Victorian house with fancy coving, this just wraps around it,” she said.
“There is lots of interest today in external insulation because people don’t want to lose internal space,” the spokesperson said. And it shows the “beauty of polymer insulation. You can insulate and render over it,” Ecotherm’s representative added.
EcoTherm’s latest product, Eco Liner, is a new PIR foam core, faced with 12.5-mm tapered-edge gypsum plasterboard. This allows users to “insulate and dry line in one simple application,” Ecotherm said. It is available for dab fixing with adhesive and for mechanically fixed dry-lining applications.
Spray foam moving into UK with BASF
BASF launched a new spray foam product called Walltite at Ecobuild, which is novel in being, “applied by trained and approved installers,” to assure the quality of the foam, said Mohamed Hussein, market development manager for SPF with BASF in the UK.
With this range, BASF is looking to achieve good energy savings, Hussein said, adding that there is now a lot more emphasis on energy efficient buildings. Also, he feels, insulation applications are better controlled and regulated than previously.
It is possible to use Walltite — coloured purple for brand identification – in “new build scenarios,” as typically done in Spain and Canada, the BASF representative said.
But he noted one characteristic of the UK market.
It has a lot of refurbishment, this is a “much bigger market” than in other parts of Europe, Hussein said.
Mainly, the foam is aimed at internal wall and roof insulation. Those are the, “two places we’re focussing on,” Hussein said.
The UK’s housing stock also has a lot of hard-totreat homes – for example those with solid walls, where cavity wall insulation is not an option. Here insulation has to be added as panels on the outside, or “by spraying the internal walls, and the same in roofs,” he added. Using SPF is space saving compared with the “excessive thickness needed with conventional mineral insulation materials,” Hussein said. “We can reduce thickness compared to ...
conventional materials to achieve the same target U values,” he added.
“That’s the beauty of Walltite versus conventional types of insulation,” added Christine Parker, of Parkdale Communications. “There’s the thickness, you can use thinner layers to give the same U values and you don’t then take so much space out of rooms,” she said. “In, say, a small Victorian house, you don’t have to spray it as thickly as you would with fibre insulation.” The spray thickness depends on the target U values.
Hussein also emphasised an important technical aspect: “The seamless nature of the product. It can reach into and fill difficult small corners and tight spots very easily and it’s not as labour-intensive as other conventional materials,” he noted.
And because it’s seamless it’s an airtight installation, he stressed.
In new-build construction techniques used in the UK, installers can use SPF for roofing and with timber-framed designs, Hussein added.
Walltite “probably takes a third of the time [to install] than needed for conventional materials,” he said. It “doesn’t need a lot of preparation, above a clean surface, as do other products.” “In the UK we’re copying the Canadian model for Walltite with a network of approved certified installers, and a bit more regulation on how the product is used. “If it’s not applied well, then you get unfair publicity on the application,” he concluded.
The key to green buildings
At Ecobuild, Kingspan was promoting its phenolic insulation, which has “the best lambda value – of 0.20 W/m2.K” and has also been rated A plus on the BRE Green Guide rating, commented Peter Morgan, marketing manager for Kingspan Insulation Ltd.
Kingspan can “also achieve that rating with our foil-faced PIR [polyisocyanurate foam], but not with tissue-faced PIR,” because the foil improves the performance, Morgan added.
Because the low lamda value means it can be thinner for a given insulation value, phenolic foam is good for refurbishment, he said.
Discussing PIR foam, Morgan described it as a commodity – “lots of people make it,” including Kingspan. In fact the group is the largest PIR insulation maker in the UK and believes it’s “the only maker of phenolic foams in the UK,” Morgan said.
According to Morgan, meeting the Green Guide eco rating of the BRE (the Building Research Establishment) “is really important because more local authorities are specifying such A+ ratings for building materials for public projects.” But there is a corresponding perception in the market that “lots of A+ products will give you a brilliantly performing building. It doesn’t work like that,” he stressed.
“You could have lots of A+ products in your construction and still not achieve a good overall rating,” Morgan added.
“But insulation is the key and buildings need that A+ rating because that’s used for the BREEAM rating (BRE Environmental Assessment Method), for the building overall,” he added.
Waiting for new UK Part L
EcoTherm recently issued a new guide on how to meet UK Building Regulations for insulation.
The company notes that, in the past, this was “relatively straightforward. A table would tell you the U-value that needed to be achieved for a particular floor, wall or roof and the manufacturer could then tell you what thickness of insulation you needed to achieve that value.” Now, “the requirements have not only become tougher, but also harder to put into a simple formula,” said EcoTherm.
The current Part L of the Building Regulations (Conservation of Fuel and Power) took effect in 2006. It applies to new buildings and to work on existing buildings.
On new buildings, the company points out the new Part L sets overall performance standards rather than laying down particular ways of achieving them. “The Elemental Method and Target U-Value approach of determining whether a building is compliant are no longer allowed,” EcoTherm emphasises.
Every new building now has to achieve a Target CO2 Emission Rate (TER) expressed in mass of CO2 per unit floor area emitted by all the internal heating, hot water, ventilation and fixed lighting. This is calculated using either the Government’s Standard Assessment Procedure (SAP 2005) for dwellings smaller than 450m2, or the Simplified Building Energy Model (SBEM) for non-domestic buildings.
It is now much harder to know how to comply, EcoTherm said, which is why it has issued the guide to help customers meet these new requirements, listing the following.
Sensible starting point for TER calculations Element U-value (W/m2.K) Thickness (mm) Wall 0.25-0.30 50 70 Floor 0.20-0.22 50 80• Roof 0.16-0.20 110 130 • Depends on floor perimeter/area measurement