I Bought Insulation Myself — What VAT Rate Applies?

If you buy insulation materials from a builder's merchant yourself, you are charged 20% VAT. The 0% energy saving materials rate only applies to a supply-and-install contract where a VAT-registered contractor both supplies the materials and installs them. A merchant sale of materials (without installation) is standard-rated at 20% — there is no reduced rate for a customer purchasing insulation products directly.

Supply-and-install

Why this matters

The ESM 0% rate is designed to reduce the cost of professional installation of qualifying energy saving measures. It is not a general discount on insulation products. If you self-manage your renovation and source materials separately, your insulation materials are 20% — the same as any other builder's merchant purchase.

The key distinctions

20% — customer buys insulation from a merchant

A builder's merchant selling insulation boards, rolls, or loose-fill to a homeowner charges 20% VAT. This is standard rate regardless of how the insulation will be used. There is no reduced rate for self-supply of materials.

0% — contractor supplies and installs qualifying ESM

A VAT-registered contractor who both supplies the qualifying insulation materials and installs them makes a qualifying ESM supply charged at 0% until 31 March 2027. Both supply and installation must come from the same contractor.

20% — installation only (customer-supplied materials)

If a contractor installs insulation that you have supplied, they are making a supply of installation services only. HMRC's position is that the combined supply-and-install is what qualifies for the 0% rate — installation alone on customer-supplied goods is standard-rated at 20%.

Action needed — reconsider who supplies the materials

If you are planning to buy insulation materials yourself and then have a contractor fit them, consider whether asking the contractor to supply-and-install instead would qualify the whole supply for 0% and reduce the total cost.

Practical checklist

Confirm whether your contractor will supply and install the insulation, or install only
If contractor is supply-and-install, confirm they apply 0% to the whole supply (materials + labour)
If you buy materials yourself, expect 20% at the merchant — there is no route to reduce this
Consider structuring your contracts so the contractor takes on supply responsibility for ESM elements
Ask the contractor for a written statement of the VAT rate they intend to apply and the basis for it
Retain the insulation specification and any manufacturer energy-rating certificates

HMRC notice references

HMRC Notice 708/6 Paragraph 2.2—Supply-and-install requirement for ESM zero-rating

HMRC Notice 708/6 Appendix A—Qualifying energy saving materials list

VATBuild is not affiliated with HMRC. References to HMRC publications are for informational purposes. Always consult a qualified tax adviser before making decisions about VAT on your project.

How VATBuild helps

What VATBuild checks for this situation

VATBuild identifies on each invoice whether a contractor is making a qualifying supply-and-install ESM supply (eligible for 0%) or an installation-only supply against customer-supplied materials (standard-rated). It flags any line where the rate applied does not match the actual supply structure.

Extension with insulation VAT Energy saving materials VAT Mixed quotation VAT