UK · Updated 2026 · Explainer
Part Z & Embodied Carbon: Using Surplus Surplus Rockwool & Mineral Wool in Ipswich
Whole-life carbon assessments are becoming mandatory on Ipswich projects. Reclaimed and surplus mineral wool is the fastest lever for reducing A1–A3 embodied carbon in East of England. This 2026 guide shows the numbers and the evidence you need.
Embodied carbon savings
Reclaimed mineral wool typically avoids 60–95% of the A1–A3 embodied carbon of a new equivalent. On a mid-size Ipswich project this can equal 4–12 tonnes CO₂e avoided.
Part Z timeline and what it requires
- Whole-life carbon assessment on all major projects
- Reporting to a central UK register
- Alignment with RICS WLCA methodology
- Evidence of material provenance
Building a compliant evidence pack in Ipswich
- Yard invoice with weight/quantity
- Photos and batch references
- Manufacturer EPD comparison for baseline
- Site delivery notes
Cost of mineral wool vs carbon benefit
| Grade | Typical price | Notes |
|---|---|---|
| Job-lot / bulk | £12.00 per pack | Merchant clearance, palletised |
| Standard graded | £27 per pack | Sorted, ready-to-fit stock |
| Heritage / premium | £42 per pack | Character grade, hand-picked |
Frequently asked questions
+Is Part Z law yet?
Not yet fully — it's a private-members bill and industry alignment. Adoption on public and BREEAM projects is already widespread.
+How is carbon quantified for surplus?
A1–A3 emissions are usually set to zero for genuine reclaim; A4 (transport) uses actual distance.
+Can mineral wool get wet?
Recovers if it dries fully within 48 hours. Prolonged saturation permanently reduces R-value.