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Reclaimed surplus insulation & plasterboard — Rockwool RWA45 50mm slabs (30 packs · ≈90m²) — LondonReclaimed Job lot

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

London·30 packs · ≈90m²·Listed 17d ago
£455/lot
~60kg CO₂e saved

Sold by London Reclaim Co. (Demolition) · Ref L0430

Contact sellerHow buying works

Condition grade 7/10 (Reclaimed). 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 London — collection or arranged regional delivery available. Direct from London Reclaim Co., a demolition operating out of London; live for 17 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 sold as reclaimed: character included, surprises excluded — read the defect notes below before bidding your time.

Measurements & specifications

Density
45 kg/m³
Thickness
50mm
Location
London
Ref
SB-43-00
Quantity / lot size
30 packs · ≈90m²
Thermal conductivity
λ 0.027 W/mK (per facing print)
Board squareness
Checked diagonal-to-diagonal on 5 sample boards
Edge profile
Square edge
Storage
Flat-stacked, dry, off the ground since arrival
Facing condition
Foil/paper facings intact on 95% of boards

Condition report & known defects

7/10
  • Surface weathering consistent with age — structurally sound throughout.
  • Expect natural variation in tone and texture across the batch — this is the appeal of reclaimed stock.

Carbon & sustainability notes

Reusing this material saves roughly 60 kg CO₂e versus producing virgin PIR/mineral wool boards (PIR ~3.5 kg CO₂e per m² at 100mm).

That's equivalent to about 354 km of average petrol-car driving, or what 3 mature trees absorb in a year.

Reuse is the single fastest way to cut a build's embodied carbon — substitution beats offsetting every time.

Collection & delivery

  • Buyer collection in London; forklift loading available weekdays 7:30am–4pm.
  • Regional pallet delivery can be arranged from £90 depending on postcode and lead time.
  • Inspection before purchase is encouraged — bring a tape and check sample units against the measurements above.

Typical applications

  • Floor insulation under screed or chipboard
  • Dot-and-dab and stud-wall drylining
  • Garage conversions and garden offices
  • Acoustic upgrades between floors

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.

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