Here is a page dedicated to questions frequently asked by our customers.

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Can I get a Green Homes Grant if I'm receiving a Renewable Heat Incentive?

The Domestic Renewable Heat Incentive (RHI or DRHI) is a government-backed financial incentive that is run through Ofgem and designed to help promote the use of renewable heating systems. Households with qualifying renewable technologies can join the scheme, and they will receive quarterly payments for seven years for the amount of renewable heat their system has produced.

If you’re receiving a DRHI, you can get a Green Homes Grant to cover the cost of energy efficiency measures such as wall, floor and roof insulation, external wall insulation and new heating controls. As long as you’re only installing energy efficiency measures through the Green Homes Grant (and no renewable heat technologies), there will be no overlap between the two schemes, and they can be used together seamlessly.

However, if you’re planning to use the Green Homes Grant to cover the cost of renewable heat technologies (such as biomass boilers, air-source heat pumps, ground-source heat pumps or solar-thermal systems), and also want to receive RHI payments for that system, then you’ll need to claim the Green Homes Grant first and then notify Ofgem. The amount you receive through the Green Homes Grant will then be deducted from your RHI payments.

Since Green Homes Grants can only be used to cover the cost of new installations, you cannot get a grant for a system that you are already receiving RHI payments for. If you are already receiving RHI payments and want to install an additional renewable heat system, then you would need to apply for the grant first, then notify Ofgem.

If your Green Homes Grant is only for measures that will improve the energy efficiency of your home, and you’re not installing any new renewable heat technologies, then there will be no overlap between the schemes, and no need to contact Ofgem.

To find out more about the Green Homes Grant and the solutions available from Saint-Gobain, please get in touch.

Can I get a Green Homes Grant if I've received ECO funding?

If you have received an ECO grant, yes, you may also be eligible for a Green Homes Grant. However, the grants cannot be used to pay for the same measures.

Also known as the Affordable Warmth scheme, The Energy Company Obligation (ECO) is a government-backed programme intended to help make UK homes more energy efficient. Through the scheme, large gas and electricity suppliers are obliged to help customers with the costs of upgrading their homes to reduce heating bills. Around £640 million is available across the UK to cover energy efficiency measures such as wall, floor and roof insulation and new heating controls.

As long as your ECO funding and Green Homes Grant are being used to pay for different energy efficiency improvements, then you can claim both. So, for example, if you have received an ECO grant to help cover the costs of internal wall linings, you could use the Green Homes Grant to pay for external wall insulation or a ground-source heat pump.

To learn more about the solutions available from Saint-Gobain, please contact us.

Can Isover CWS be used below DPC level in masonry cavity walls?

ISOVER CWS is manufactured with a water-repellent binder, meaning that it can safely be used below DPC level in masonry cavity walls without the risk of ground moisture bridging the DPC via capillary action.

Can ISOVER Spacesaver be used in a sloped or vertical application?

ISOVER Spacesaver is a low-density loft insulation roll, and as such we would only recommend it be used in a horizontal application as it may not self-support in any sloped or vertical application.

Can more than one company carry out Green Homes Grant installations on the same home?

Yes, multiple installation providers can work together to carry out work on a single home through the Green Homes Grant. Each measure will need to be quoted separately, and a separate voucher applied for.

This is expected to happen often, as the Green Homes Grant covers many types of energy efficiency measures, many of which require different skills and knowledge. For example, a homeowner would probably need several companies to install solid wall insulation, double glazing and a ground-source heat pump.

For more information about the Green Homes Grant, as well as insulation installation training in relation to the scheme, please register your interest with Saint-Gobain Insulation UK.

Do I need to use membranes when installing PIR below a concrete slab or screed?

First of all, ensure that the PIR insulation boards are laid above the damp proof membrane (DPM). The foil facings of our PIR insulation boards may be damaged by wet screed or wet concrete, allowing gas to escape that may weaken the floor topping so we would always recommend a membrane be used for protection over the PIR insulation boards once they have been laid & prior to the screed or concrete topping being poured.

Do I need to wear PPE when installing your insulation products?

Our safety data sheets provide information on the precautions that should be taken when installing our MW or PIR insulation products.

Does your insulation attract rodents or other vermin?

Our insulation offers zero nutritional value to vermin, although if rodents can access the insulation they may use it as a nest.

Green Homes Grant: how do contractors get paid?

To get paid through a Green Homes Grant voucher, you'll need to register as a contractor on GOV.UK. To do that, you'll first need to be registered with TrustMark.

When you register as a contractor for the Green Homes Grant, you'll be asked to provide a few details about your company, including the area in which you will carry out work and the type of installations you can do. You will also need to agree to the scheme's terms and conditions and enter your bank details so you can be paid.

Before carrying out any work under the Green Homes Grant scheme, you must have received confirmation of successful registration, and a voucher must have been issued for that specific measure.

As a registered contractor, customers can contact you for quotations and carry out work such as the installation of loft insulation or solid wall insulation. Once the project is complete, there are a few items of administration that must be completed within 14 days, including uploading specific project information to the TrustMark Data Warehouse where it may be reviewed for compliance, and providing the customer with an invoice and guarantee where appropriate. The voucher redemption process may then start and following certain confirmations by both the customer and installer with the scheme administrator, payment will be issued. It has been confirmed that this can all be achieved, and voucher payment received by the contractor in less than 12 days.

All work will need to be completed and lodged at least seven days before the vouchers expire, Vouchers are valid for three months, and the expiry is either the three-month validity or the end of March 2021, whichever is sooner. In certain circumstances, voucher applicants can apply to extend the expiry date past the three months but not past the end of March 2021. Further information may be found in the scheme’s customer and installer specific terms and conditions.

For more information on the Green Homes Grant scheme, including information on our loft insulation training, click here.

How do I find a TrustMark-approved contractor?

If you're considering getting work done through the Green Homes Grant - such as the installation of floor insulation or draught-proofing, you must use a TrustMark-approved contractor to carry out the work.

Finding a TrustMark-approved contractor is simple. Either visit the SEA website - within the description page for each measure, there is the ability to search for an installer - or, for a more comprehensive list, visit the TrustMark website and use the find a local tradesperson tool.

To use the tool, you need to enter your address and the type of work you'd like completed. It will then generate a list of potential contractors with a map showing their locations, along with contact information and other relevant company information.

For more information and advice about insulating your home through the Green Homes Grant, please download our Green Homes Grant Insulation Guide.

How should PIR products be stored?

Our PIR insulation boards should be stored in their original packaging, protected from the weather and clear of the ground. Any damaged boards (e.g. crushed corners) or wet boards should not be used.

For any further queries please contact our Technical Support Centre

Must suppliers be approved on the Green Homes Grant?

While contractors carrying out installation work through the Green Homes Grant must be TrustMark registered, the scheme does not set out any specific requirements about which products are used or which suppliers they are purchased from. However, the products or systems will require some form of warranty or guarantee and, dependent upon the system, this may be provided by the certification scheme, manufacturer or another third party.

By being TrustMark registered, contractors have demonstrated their ability to comply with PAS 2030. This means they already have the training and knowledge to source products that meet the required safety and performance standards - such as our range of thermal insulation.

When delivering energy efficiency measures under the Green Homes Grant scheme, use our website to search for stockists of Celotex and ISOVER products.

Once installed, how long will your insulation last in my building?

Once installed, if left unmolested and undisturbed we can say that the insulation will perform for the expected lifespan of the building into which it is installed, which is generally taken to be 60 years.

What costs does the Green Homes Grant cover for contractors?

Under the Green Homes Grant scheme, the government issues vouchers for up to two-thirds of the cost of certain energy-efficient home improvements, up to the value of £5,000 per household. Up to £10,000 may be available for lower income homes, covering 100% of the upgrades up to the £10,000 voucher limit. The costs covered by the scheme include the costs of materials, such as floor insulation and cavity wall insulation, as well as labour. Some other costs that are directly related to the installation of energy efficiency and microgeneration measures are also covered.

The government has published a comprehensive list of costs that are and are not covered; it can be downloaded here. Highlights of the list of covered costs include:

  • Professional services to ensure compliance with standards: design drawings and calculations, damp specialist and structural engineer costs, modelling to evaluate moisture risk, airtightness tests, modelling to estimate payback.
  • Contractor costs: labour and materials, scaffolding, waste removal, VAT.
  • Reasonable enabling work: necessary structural improvements, repairing and treating damp, repairing and improving controlled ventilation.

The voucher will not cover costs that are not directly related to energy efficiency measures. Some of the other things not covered by the voucher include:

  • Energy Performance Certificates (EPCs), building surveys and building design work not linked to a Green Homes Grant retrofit.
  • Training costs for contractors
  • Asbestos removal
  • Re-roofing
  • Electricity or gas safety work
  • Changing the layout of the property (such as moving windows or doors)

To find out more about what kinds of work are included on the Green Homes Grant, read our FAQ: What's the difference between primary and secondary improvements on the Green Homes Grant?

Contractors must be TrustMark approved to carry out work through the Green Homes Grant, and Saint-Gobain Insulation UK offers training to help installers demonstrate compliance with the competence requirements for gaining the required certification. To find out more, or sign up for our next course, please register your interest.

What is a Euroclass ‘reaction to fire’ rating?

A Euroclass ‘reaction to fire’ rating is a measure of a product’s behaviour when exposed to a direct ignition source. The behaviour is classified as A1 through to F, with A1 attaining the highest level of performance and F the lowest level of performance.

What is PAS 2030 accreditation?

PAS 2030 is a specification covering the installation of energy efficiency measures in existing buildings. PAS 2030 includes requirements for installation, process management and service provision. It also includes criteria relating to installation methods, equipment, tools, product or system selection and material suitability.

The commissioning of installed measures and the training, skills and competence of the people undertaking such installation is also covered in PAS 2030. Contractors carrying out work through the Green Homes Grant must be TrustMark registered, which requires certification to PAS 2030.

The framework was developed in response to the Each Home Counts (Bonfield) review, which found the quality and performance of many energy efficiency and renewable energy retrofit projects was insufficient. In particular, it addressed the concern that many such projects were often carried out without adequate consideration for what was best for the property and its occupants.

Since its original publication, PAS 2030 has been redeveloped, and we are currently in a transition phase between PAS 2030:2017 and PAS 2030:2019. Because of this, contractors with an existing certification can register with TrustMark using either version of PAS 2030. However, switching your certification to PAS 2030:2019 sooner is recommended. Those contractors who were not certified to a PAS 2030 standard before the scheme launched will need to work towards PAS 2030:2019 certification.

Saint-Gobain Insulation UK offers training to help contractors ensure they are meeting the required standards when installing wall insulation, roof insulation or floor insulation. To find out more or to register for our loft insulation training, please register your interest.

What is SEA (Simple Energy Advice)?

Simple Energy Advice (SEA) is a website that has been developed in conjunction with the Department for Business Energy and Industrial Strategy (BEIS). It provides trusted recommendations and impartial advice for private homeowners, landlords and local authorities on how to improve a dwelling's energy efficiency.

The SEA website has a guide to the Green Homes Grant, an eligibility checker and a tool to help you find out what energy efficiency measures you could have installed through the Green Homes Grant - such as loft insulation or a ground-source heat pump. It also offers advice on finding a contractor and getting a quote for work.

If you're looking for more information about how to insulate your home through the Green Homes Grant, please download our Green Homes Grant Insulation Guide.

What is the best way to cut Mineral Wool or PIR insulation?

Specialist insulation saws and knives are widely available, these should be used to trim or cut our insulation products when required.

What is the Green Homes Grant?

The Green Homes Grant is a government-funded voucher scheme that was launched to incentivise and help homeowners pay for energy efficiency retrofits and upgrades. The grant was announced in July 2020 and opened for applications at the end of September. It is currently scheduled to finish at the end of March 2021.

Through the Green Homes Grant, qualifying homeowners can get vouchers for up to £5,000 to cover up to two-thirds of the total cost of work. Lower-income households may be eligible for grants of up to £10,000 covering 100% of the cost up to the voucher amount.

To be eligible for a Green Homes Grant, you must live in England and:

  • Own your own home or park home on a residential site or
  • Be a residential landlord in the private or social rented sector.

The vouchers can be used to pay for a variety of energy efficiency measures, such as solid wall insulation, floor insulation, loft insulation, ground-source heat pumps, draught-proofing and new heating controls. The various measures have been split into primary and secondary categories, and at least one installation must be from the primary category.

Further details about the scheme, as well as the application for vouchers can be found at the GOV.UK Green Homes Grants webpage. Contractors can also register for our upcoming course to gain the skills and knowledge needed to become an approved installer on the scheme.

What is the TrustMark Data Warehouse?

The TrustMark Data Warehouse is a repository of information about work that has been undertaken to improve the energy efficiency of domestic homes in the UK. It acts as the industry-facing side of the Property Hub, which is the consumer-facing platform that provides homeowners insight about their property and what kinds of improvements or changes have been made over the years - such as the installation of loft insulation.

Contractors must lodge details of works carried out through the Green Homes Grant in the Data Warehouse. Lodging work in the Data Warehouse is also required as part of PAS 2035 and, therefore, any work carried out by a TrustMark-approved contractor will be added to the system.

For more information and to get updates about training related to TrustMark and the Green Homes Grant, please register your interest with Saint-Gobain Insulation UK.

What is TrustMark?

TrustMark is a quality scheme endorsed by the UK government. It covers work that a homeowner chooses to have carried out on their home, and was implemented to help consumers ensure that they are working with contractors who will deliver to its three cornerstones of quality:

  • Technical competence
  • Good customer service
  • Good trading practices

Contractors who are approved by TrustMark will have been accredited to specific standards and, in the case of energy efficiency installations, this includes certification to PAS 2030. Depending on the type of work a contractor carries out, other qualifications, such as MCS certification, may also be required to be TrustMark approved.

TrustMark is intended to give consumers confidence about having work done on their homes. Contractors operating through the scheme may be able to offer their customers certain benefits, such as financing options offered through a network of scheme partners. TrustMark also offers a range of solutions should problems arise.

To carry out installations through the Green Homes Grant voucher scheme - such as the installation of cavity wall insulation or solar thermal heating - contractors must be TrustMark approved.

To find out more about getting TrustMark approval, and receive notifications about upcoming training opportunities, contractors can register with Saint-Gobain Insulation UK.

What's the difference between primary and secondary measures on the Green Homes Grant?

To ensure that works carried out through the Green Homes Grant provide sufficient improvements to the housing stock, the government has separated the various applicable measures into two categories: primary and secondary.

Primary measures include thermal insulation and low-carbon heating, such as:

The secondary measures include:

  • Draught proofing
  • Double, triple or secondary glazing
  • Upgrading to energy-efficient doors
  • Heating controls

To qualify for a Green Homes Grant, at least one primary measure must be installed, and the amount provided for secondary measures must not be more than the cost of the primary measures. So, for example, if you choose to have loft insulation installed for £1,000, then you can also request funding for secondary measures up to £1,000 but not over.

It's important to know precisely what type of work will be covered by a Green Homes Grant voucher. For example, it cannot be used for like-for-like replacements or repairs of existing systems. In terms of insulation, the grant will not cover:

  • Insulation of new extensions that have current building permission
  • Extensions without building permission or planning permission
  • Extensions and conservatories without fixed heating
  • Outbuildings

Also, solar photovoltaic (PV) installations are not covered by the Green Homes Grant. If you're looking for funding for solar electricity or other types of micro-generation systems, you may want to consider the Smart Export Guarantee.

If you'd like more information and advice about insulating your home through the Green Homes Grant - a primary measure on the scheme - please download our Green Homes Grant Insulation Guide.

Where can I find the Declaration of Performance (DoP) for your insulation products?

Visit our webpage dedicated to our Declarations of Performance to download the appropriate DoP for your product, or alternatively look for a link on the relevant Product Page.

Why does the TrustMark scheme accept the 2017 and 2019 versions of PAS 2030?

We are currently in a transition period between the two versions of the PAS 2030 standard. Because of this, contractors with an existing certification can register on TrustMark based on either version. Those contractors who were not certified to a PAS 2030 standard before the scheme launched will need to work towards certifying to PAS 2030:2019.

The first version of PAS 2030 was launched in 2017. It has since been redeveloped in conjunction with PAS 2035, and a new standard covering the retrofitting of dwellings for improved energy efficiency has been published. So, we now have:

  • PAS 2030:2017 - This is the original specification for the installation of energy efficiency measures, such as loft insulation and floor insulation in existing buildings. It covered topics from design, through installation to commissioning, as well as other processes, competencies and quality management requirements.
  • PAS 2030:2019 - This is the redeveloped specification. It provides guidance for retrofitting dwellings for improved energy efficiency, covering the installation, commissioning and handover of retrofit projects.
  • PAS 2035:2019 - This sets out a holistic approach for assessing a property, identifying improvement options and designing and specifying energy efficiency measures. It also takes a long-term view of monitoring efficiency and suggesting further improvements over a 20-30 year period.

Parts of PAS 2030:2017 were moved to the new PAS 2035 standard, so PAS 2030:2019 is a condensed version of its predecessor. However, PAS 2030:2019 certification requires compliance with PAS 2035, ensuring the requirements that were moved to the new standard are still covered.

The transition period ends in June 2021; after that, TrustMark will require contractors to be certified to PAS 2030:2019. Since this happens after the Green Homes Grant scheme is scheduled to finish in March 2021, contractors through the Green Homes Grant do not necessarily need to update their certification to take part in the scheme. However, updating your processes and certification sooner is advised, as it will help to ensure you're providing the best service possible to your customers and could protect your business as well.

Saint-Gobain Insulation UK’s offers loft insulation training, which provides contractors with the information and skills needed to demonstrate compliance for TrustMark approval. To find out more or sign up for our next course, please register your interest.

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Take a look at our collection of questions. If your query cannot be answered on this page, please contact the Technical Support Centre on 01473 820850

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