An Interview with James Hulbert – Head of Housing, Knauf Insulation

[vc_row uxb_theme_class=””][vc_column uxb_theme_class=””][vc_column_text]In our new interview series, we talk to industry-leading product providers to learn more about their roles, changes in the industry and hot topics in the field.

In our second interview, we talk to James Hulbert, Head of Housing for Knauf Insulation in the UK.[/vc_column_text][/vc_column][vc_column uxb_theme_class=””][vc_column_text]Hello! Can you tell me your name, your position at Knauf Insulation and which sector you are involved in?

I’m James Hulbert, Head of Housing for Knauf Insulation in the UK.
‘Low rise, repeatable, volume housebuilding’ is as simple a definition as I can give you for the team’s sector. We primarily focus on national and regional developers in terms of unit numbers, though we are not prescriptive in volumes.

(For those not quite sure, the K isn’t silent, Knauf is pronounced ‘C’ (as in curly ‘c’)…‘now’…‘f’.) (…not Norf)

Which elements of the building fabric are Knauf Insulation products situated? What are those products?

For housebuilders and developers we’re best known for wall and loft systems and products;

External and Party Walls

• Supafil® – blown fibre, in situ formed, full-fill cavity wall systems fitted by Approved Installers
• Earthwool® DriTherm Cavity Slabs– built-in, full-fill, installed by your Bricklayers
• Earthwool FrameTherm Roll and Slabs – built-in, timber frame walls

Roofs, Floors, Partitions – Earthwool®

• Loft Roll – I don’t need to tell you where loft roll goes do I?
• Rafter Roll – you can probably figure this one too. Good for room in roofs, FOGs too.
• OmniFit Roll – best for floors over garages as it’ll fully fill between I-Joists (unlike Loft Roll)
• Acoustic Roll – all mineral wool is good at absorbing sound, this looks after internal partitions and floors.

You’ll also find our material in our partners’ complementary products, roof cassettes for example, as well as Eaves Insulators, T-Barrier®, cavity stop socks and the like.

How are they made? How sustainable are they?


…simplistically, we melt glass (predominantly recycled) for glass mineral wool and rock for…rock. We draw the molten material into a fibre, cut and package it into insulation.

For housing, we make two types of product, ‘cured’ and ‘loose’; cured product is Earthwool, has a distinctive brown colour and also smells OK too. It looks, feels (and smells) the way it does as the fibres are ‘glued’ together with our unique binder, ECOSE® Technology. We developed this with natural raw materials some time ago anticipating a demand to reduce phenol and formaldehyde usage in the supply chain. ECOSE® Technology products have neither of these chemicals added to it we’re pleased to say.

Supafil defines our ‘Loose’ products; for housing these are predominantly cavity wall and party wall systems, we melt and draw the raw materials in very much as we do for cured material, we just don’t apply the binder. These can then be blown into cavities, party walls (and framed constructions too) to the required density to achieved the target performance.

We talk about contributing to the comfort standard of a house; saving energy, acoustic wellbeing, health and safety too. The positive environmental impact during the use phase (energy saving) far outweighs that of production in a quite startling ratio of between 1:100 and 1:500 (with variances attributable to product and application type.)

We look to internationally recognisable platforms to demonstrate performance at both company and product level. Eurofins is a one such example of where we led not only the industry but the world in achieving that certification.

Earthwool and Supafil products all achieve ‘Eurofins Indoor Air Comfort Gold Standard, (a mouthful I know, and unlike ‘Knauf’, I can’t tell you how to pronounce Eurofins) certifying them as ‘an outstanding material according to the VOC Indoor Air Quality emissions regulations’.

Similarly, we’re soon to announce the addition of the Declare Label to our Supafil products, grandly titled as a ‘transparency platform and product database’ Declare has a very high disclosure threshold (> 100 ppm), allowing our customers to see where Supafil comes from, what it’s made of and where it goes at the end of its life.

I understand you have a new state of the art processing plant, which leads me to ask how has Knauf Insulation addressed climate change in its production process and how much is made from recycled waste?

We do like the Veolia partnership, and I’ll try to talk about it without using the term ‘circular economy’ too.

We are fortunate that we don’t need a specific colour of raw material, we’re able to use all sorts of recycled glass. At the beginning of 2017, we wanted to increase the average recycled content and future-proof our supply chain too; our incumbent suppliers couldn’t guarantee the quality, quantity or consistency required to achieve this. So we bought a plot of land less than a stone’s throw from our St Helens plant, partnered with waste management company Veolia, they invested the £10 million required to build the processing facility, which then opened in January 2018.

The facility processes over 60,000 tonnes of glass a year (350 million bottles of all shapes and sizes) and, being next door to the factory also saves around 375,000 miles of road journeys each year. The energy saved by recycling a single glass bottle equivalent to that needed to power a 100-watt light bulb for an hour.

We’ve held ISO 14001 since 1999, which defines the criteria of our Environmental Management System (EMS) that has helped us manage our environmental responsibilities since then.

We’ve also recently transitioned from ISO 16001 to adopt ISO 50001, our Energy Management Standard. This is designed to help tackle climate change by reducing greenhouse gas emissions, improving efficiency and reducing our energy consumption.

Since 2010 we’ve reduced our CO2 emissions by 20%; in the UK we’ve done this through various projects, one a partnership with Siemens which led to a comprehensive energy management programme being implemented to our two glass mineral wool plants, which monitors and reduces energy consumption and helped us to achieve our 20% target reduction well before its original commitment.
We have now taken a commitment to reduce the embodied carbon of our products further, by 15%, by 2025 (from 2019), and to create a clear roadmap towards zero carbon.
Less dramatic and without terms like ‘strategic’ and ‘roadmap’, we have the industry’s most advanced compression packaging (with a compression ratio of up to 9:1 unpackaged to packaged volume), giving more product and less packaging per pack delivered with fewer vehicles and carbon emissions.

Our glass [mineral wool] is made of up to 80% recycled materials, and never less than 50% depending on the product, mostly recycled glass bottles and jars, the stuff you put in your local bottle bank. One of our partners’ average new-build house, to ADL 2013, will have the equivalent of over 550 recycled wine bottles in it, (that’s some party!)

What do you see as the future for mineral wool insulation in terms of Future Homes Standard?

We don’t see The Future Homes Standard in isolation but set its ambitions alongside the New Homes Ombudsman Scheme that will go live this year.

A strong theme in both policies is a demand for greater assurance that the customer gets the home quality and performance they have paid for.

The next iteration of [Approved Document] Part L has a long list of new quality control requirements including photographing key build stages and recording a list of materials used while the New Homes Ombudsman Scheme will have home ‘fuel & energy’ performance in its remit and the capacity to fine the developer up to £50,000 per home.

Developers that simply chase a target U-value, tick the box and consider that ‘job done’ will be in for an expensive shock.

In this context, we believe well installed mineral wool has a strong future in de-risking future liabilities and delivering high performing homes.

Indeed, we are innovating to develop quality control support tools to complement the core ‘fit-ability’ of our mineral wool.

I understand you have a site monitoring programme in place, can you elaborate as to why this is vital in addressing the Performance Gap?

We have two in fact, both very different, both contributing to our confidence of a strong future for Knauf Insulation mineral wool in new build housing.

First of all, we support our blown-in Supafil cavity systems at point of install;

We have a Contracting Team with Regional Technical Managers (RTMs) who educate, train and surveil our approved installers and their technicians. Our Agrément Certification mandates that each technician must have their workmanship reviewed once a year, we look to a minimum of twice.

The RTMs work with both installers and site teams discussing when a plot is suitable for install (and crucially, when not), addressing any local questions and, in extreme situations, policing the system with a yellow and red card protocol.

Supafil has been a popular choice of cavity insulation in new build housing for many years, we have a great resource in the Housing Team to work with developers’ Regional Teams and third parties such as the NHBC, while the Contracting Team works with our installers and site teams.

Supporting all parties shortly will be our Track and Trace App (COVID may well have put paid to the working title!), that enables the technician to log the location, plot and equipment details of a Supafil installation along with product type and quantity.

Secondly, and from the perspective of monitoring, learning and addressing real building performance is Knauf Energy Solutions;

Digitalisation, executed by way of multiple sensors, cloud computing and machine learning –combining to allow highly accurate measurement of home fabric efficiency.

A variety of technologies are already being evaluated as part of a UK Government programme while we have been conducting large trials on our solutions and systems in both new build and older retrofitted homes. The results for our mineral wool have been very encouraging where installation has been quality controlled.

Some time ago, we believed the next iteration of Part L would be the last to set out targets solely in terms of tick box compliance exercises delivering only theoretical performance. Design target U-values would, we believed, ultimately be backed up by onsite performance evaluation if the journey to greater customer assurance – and the closure of the energy and carbon performance gap – was to be achieved.

Arguably, with the introduction of the New Homes Ombudsman Scheme, that real performance requirement for every home will soon exist as a potential liability on the balance sheet of up to £50,000 per home.
In terms of External Wall and Party Wall insulation, what are the main advantages of blown fibre over mineral wool batts, if any?

We manufacture both solutions, with Supafil and Earthwool DriTherm, both offering robust, cost effective solutions that are easy to do well and, difficult to do badly.

Supafil (blown-in)

• Typically enables properties to be built quicker [than built-in solutions] as the bricklayers can progress with what they prefer to do, namely lay masonry.
• The cavity to be left clear during construction requiring less protection during inclement weather as well as providing good visibility for Building Control.
• Is installed by approved, trained, specialist third parties and policed by our Regional Technical Managers.
• No product is held on site, freeing up storage space and mitigating potential theft.
• Blown solutions install the correct amount of product, and no more, with no waste and our LDPE-4 packaging is easily recycled by the contractor.
• Blown solution rates (£/m2) show lower variation nationwide than brickies install rates for built-in, especially in the South East of England.
• In party walls, leaving the cavity clear during construction minimises the chance for moisture to be held in the party wall masonry post-occupancy, which can manifest itself in the discolouration of plasterboards when heating systems are turned on.

Earthwool DriTherm (Built-in)

• Currently we can manufacture built-in solutions with a superior thermal performance [than blown], DriTherm 32 being 0.032 W/mK and Supafil 34, unsurprisingly 0.034 W/mK.
• Builders Merchants and Distributors readily stock these materials enabling flexibility on behalf of the developer.
• Some site agents simply prefer the visibility of a built-in insulant and, being balanced, not all site managers fully appreciate that they have an important role to play in simple plot readiness prior to calling an install off of blown product.

Do Knauf Insulation products have a Global Warming Potential and how do they sit in terms of helping to address Climate Change?

Another first (it is strange what excites some of our Group), we were very keen to register the first Environmental Products Declaration for an insulation manufacturer, and we achieved that in 2014.

We monitor the environmental impact of our products through Life Cycle Assessment (LCA). These results are reported in our EPDs, are independently, third party, verified and comply with EN 15804. They are registered with the Europe-wide ECO-Platform and BRE’s UK-specific Certified Environmental Profiles scheme. Every product we manufacture in the UK is covered by an EPD.

We have clear objective to further reduce the GWP of our products.

In terms of addressing climate change in housing, we fully support the direction that revisions to ADL1a and the Future Homes Standard are taking in new-build. We are consistent in championing joined up thinking to improve the energy performance of our existing housing stock, only then can we meaningfully tackle climate change.

You always come across as very knowledgeable in relation to legislation, is this something your team are engaged with?

Yes, our specification teams are those most impacted and most impactful around regulation change.

Legislation shapes the insulation market in new build or extended homes and buildings through Building Regulations or through subsidy schemes in the retrofit sector.

It is our job, at Team, Region and Group level, to see the direction of travel in regulation and innovate to support our customers in best responding to those changes.

The Housing Team are one element in that process and, as regulation compliance in housing, perhaps more than in other construction sectors, becomes less elemental, it’s key that we can see innovation outside our products too, be that with our App, Knauf Energy Solutions or with non-competing partners.

We appreciate the construction industry is in a delicate position at present and developers are likely to have a need to cut build costs. However, cheaper products do not always mean the overall cost is cheaper. How can Knauf Insulation help cut overall costs without cutting build quality and overall performance?

We are consistent in our messaging to developers, and increasingly we look to mandate change in our supply agreements too; the higher the level of engagement we can achieve, the more we can offer and deliver.

Looking to procure individual materials like-for-like, only ‘cheaper’, can only take you so far in value engineering and quickly hits the bump stops, often negating quality and preventing design innovation too.

We don’t believe the question is as binary as ‘How can Knauf Insulation help cut overall costs without cutting build quality and overall performance?’

When working in partnership with customers, looking at linear thermal bridging details, SAP review or introducing them to a non-competing partners we can help reduce their build cost, improve buildability and quality. We do this irrespective of whether they already use our products.

We firmly believe that engaging with us yields better understanding of quality at the front end, a better performing installation and appreciably reduced remedial costs.

Finally James, can you sum in a few words why you feel Knauf Insulation is best positioned to help developers to meet the soon to be implemented ADL 2020?

We get to Question Eleven and now you ask me to only use a few words! Our focus on:

1. Proven systems
2. Quality and monitoring
3. Training
4. Partnership
5. Introduction of evidential technology

… positions us well.

As we’re talking, the 4,000 responses to the Part F and L Consultations (in England) have yet to be fully reviewed, along with the socio-economic impact of COVID-19 too, so no one can be certain as to which option we will be faced with, and crucially, when.

Whether Option One or Two, we believe the strong fabric values where we currently feature, cavities and lofts, can largely remain as they are [under ADL2013] and evolve as we transition towards FHS. Our field and technical support, from training to calculating psi-values, gives developers a strong partner who will help compliance, cost management and quality.[/vc_column_text][vc_column_text]For further information please visit[/vc_column_text][/vc_column][/vc_row]