SSurplusBuilder.
B-grade surplus insulation & plasterboard — Rockwool RWA45 50mm slabs (30 packs · ≈90m²) — LeedsB-grade Job lot

Rockwool RWA45 50mm slabs (30 packs · ≈90m²) — Leeds

Leeds·30 packs · ≈90m²·Listed 20d ago
£470/lot

Sold by Leeds Urban Reclamation (Demolition) · Ref L0433

Contact sellerHow buying works

Condition grade 6/10 (B-grade). Assessed by the seller at listing; figures below relate to this specific lot of 30 packs · ≈90m².

About this lot

Acoustic mineral wool slabs. Packaging slightly creased, product immaculate. Ideal for studwall sound insulation. Located in Leeds — collection or arranged regional delivery available. Direct from Leeds Urban Reclamation, a demolition operating out of Leeds; live for 20 days.

This is exactly the kind of material that typically ends up in a skip costing the seller money; buying it diverts it back into a build. It is graded down on appearance alone; structurally and functionally it performs as A-grade.

Measurements & specifications

Density
45 kg/m³
Thickness
50mm
Location
Leeds
Ref
SB-43-03
Quantity / lot size
30 packs · ≈90m²
Thermal conductivity
λ 0.037 W/mK (per facing print)
Board squareness
Checked diagonal-to-diagonal on 7 sample boards
Edge profile
Tapered edge
Storage
Flat-stacked, dry, off the ground since arrival
Facing condition
Foil/paper facings intact on 97% of boards

Condition report & known defects

6/10
  • Cosmetic seconds — graded down for appearance, not performance.
  • Allow a cutting/waste margin of ~10% over a normal A-grade order.

Carbon & sustainability notes

This listing carries no CO₂-saved figure because the material is new; the sustainability win here is waste prevention — first-quality stock staying out of the waste stream entirely.

With Part Z and embodied-carbon reporting moving up the agenda, documented reuse like this is increasingly worth recording in your project's carbon log.

Collection & delivery

  • Buyer collection in Leeds; kerbside hand-load or forklift by arrangement.
  • Nationwide pallet courier available — typically £35–£90 per pallet, 2–4 working days.
  • Viewings welcomed by appointment; the measurements table above reflects what was checked at listing.

Typical applications

  • Dot-and-dab and stud-wall drylining
  • Garage conversions and garden offices
  • Acoustic upgrades between floors
  • Warm roof build-ups and rafter-level insulation

Questions about this lot

Do part-sheets affect building control sign-off?+

No — what matters is the declared lambda value and installed thickness. Keep a facing photo showing the print line for your Building Regs file.

How should boards be stored on site?+

Flat, dry and off the ground. PIR facings degrade with prolonged UV exposure, so keep the wrap on until the day of fixing.

Is mixed-brand insulation OK in one roof?+

Yes, provided each zone's U-value calc uses the correct lambda for the board actually installed there. This lot is single-brand across all 4 packs.

More surplus insulation & plasterboard

View all →