Hemp insulation represented approximately 2% of all natural insulation sold in the UK in 2025, with demand rising 15% year on year, according to the Energy Saving Trust’s latest materials report (Energy Saving Trust, 2026). Hemp insulation is a breathable, plant-based material made from the woody core of industrial hemp, typically mixed with a binder such as lime or polyester fibre to form batts, rolls, or loose-fill. This article explains who can access UK grant funding for hemp insulation in 2026, who is excluded, and how to verify eligibility, drawing on data from the Department for Energy Security and Net Zero (DESNZ), Ofgem, the Microgeneration Certification Scheme (MCS), and the Energy Saving Trust.
The Great British Insulation Scheme closed on 31 March 2026. It funded insulation measures only and never covered windows or glazing.
The Great British Insulation Scheme closed on 31 March 2026. It funded insulation measures only and never covered windows or glazing. The Great British Insulation Scheme closed on 31 March 2026. It funded insulation measures only and never covered windows or glazing. The grant covers 100% of material and installation costs for eligible households, capped at £1,500 per measure. Homeowners must use an installer registered with TrustMark and certified under PAS 2035 or PAS 2030, and the installer must confirm the hemp product’s U-value on the EPC. Income thresholds and the cap are set out in Ofgem’s GBIS guidance, updated January 2026 (Ofgem GBIS guidance, 2026).
ECO4 does not explicitly exclude hemp insulation
ECO4, the Energy Company Obligation, funds insulation for low-income and vulnerable households with no fixed cap on cost per measure. Hemp insulation is technically eligible under ECO4 if it meets the scheme’s minimum energy performance standard, again a U-value of 0.30 W/m²K or lower for walls (DESNZ ECO4 Order 2026, GOV.UK). In practice, ECO4 installers rarely specify hemp because the material costs 30% to 50% more than mineral wool, according to the Energy Saving Trust’s cost comparison table using 2025 data (Energy Saving Trust, 2026). Homeowners must have an EPC of D, E, F, or G and be in receipt of a qualifying benefit such as Universal Credit or Pension Credit (Ofgem ECO4 eligibility criteria, 2026). If a homeowner insists on hemp, they must find a PAS 2035 certified installer willing to source it, and not all suppliers carry stock.
Homeowners not on benefits can still claim 0% VAT on hemp insulation
Since 2022, the UK government has applied 0% VAT on all insulation materials, including hemp, for installation in residential properties regardless of household income (HMRC VAT Notice 708/6, updated April 2026). The 0% rate applies to materials and labour when installed by a VAT registered contractor. DIY installers can reclaim the VAT on materials only. There is no income cap, no EPC requirement, and no grant application needed; it is an automatic reduction at the point of sale. This is the only universal subsidy for hemp insulation in 2026.
Quick numbers, cost, U-value, and grant amounts for hemp insulation in 2026
| Measure type | Typical cost per m² (installed) | Typical U-value achieved (W/m²K) | GBIS grant cap (per measure) | ECO4 typical contribution | 0% VAT savings |
|---|---|---|---|---|---|
| Loft insulation (300mm hemp batt) | £25–£35 | 0.14–0.16 | £1,500 | Full cost (no cap) | 20% of total cost |
| Solid wall (internal hemp-lime board) | £60–£90 | 0.28–0.30 | £1,500 | Full cost (no cap) | 20% of total cost |
| Cavity wall (hemp loose-fill) | £35–£50 | 0.28–0.30 | £1,500 | Full cost (no cap) | 20% of total cost |
Costs vary by region and installer availability. These median estimates are drawn from Energy Saving Trust cost data (2025), the MCS product database (2026), Ofgem grant cap figures, and HMRC VAT rates (Energy Saving Trust, 2026; MCS product database, 2026; Ofgem, 2026; HMRC, 2026).
Who does NOT qualify for government-funded hemp insulation
The Great British Insulation Scheme closed on 31 March 2026. It funded insulation measures only and never covered windows or glazing. The Great British Insulation Scheme closed on 31 March 2026. It funded insulation measures only and never covered windows or glazing. The Great British Insulation Scheme closed on 31 March 2026. It funded insulation measures only and never covered windows or glazing. Properties with existing insulation that already meets the minimum U-value standard are not eligible for grant funded upgrades. No grant scheme covers hemp insulation as a standalone measure; it must be part of a wider insulation project such as whole wall or whole loft.
How to verify a hemp insulation installer is certified and grant-compatible
For GBIS and ECO4, the installer must hold PAS 2030:2023 certification for insulation and be registered with TrustMark (TrustMark register, GOV.UK, 2026). For any grant scheme, the installer must also be on the Ofgem approved list for that specific programme, which can be checked via Ofgem’s online portal. For non grant funded installations using 0% VAT only, the installer must be VAT registered; confirm this via HMRC’s VAT number check tool. Hemp specific certification is required if the hemp product is part of a renewable heating system, such as hemp lime in a heat pump house, in which case look for MCS certification (MCS register, 2026). Otherwise, no additional hemp specific certification is needed beyond PAS 2030 and TrustMark.
Hemp insulation is grant-eligible in the UK in 2026
The Great British Insulation Scheme closed on 31 March 2026. It funded insulation measures only and never covered windows or glazing. No grant covers hemp insulation for higher income homes or those with good EPC ratings; the 0% VAT relief is the only universal support. The Great British Insulation Scheme closed on 31 March 2026. It funded insulation measures only and never covered windows or glazing. guide to checking your EPC rating and eligibility for insulation grants overview of natural insulation materials and their performance
Frequently Asked Questions
Hemp insulation costs £15 to £25 per m² installed, depending on thickness and supplier. The Energy Saving Trust reports this range for 2026, with materials making up 40-50% of the total.
Ofgem's 2026 guidance confirms this for households with an EPC rating D-G and income under £31,000.
Yes, ECO4 funds hemp insulation technically, but practical barriers like MCS certification for installers limit uptake. The Energy Company Obligation has no fixed cap, but the installer must be TrustMark-registered and PAS 2035 certified.
The installer confirms this on the EPC, per Ofgem's technical specification.
No, grants require installation by a TrustMark-registered professional certified under PAS 2035 or PAS 2030. The Great British Insulation Scheme closed on 31 March 2026. It funded insulation measures only and never covered windows or glazing.
