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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

How to buy, collect and install this lot

  1. 1Confirm your requirement against the measurements above — bring a tape and the 30 packs · ≈90m² figure when you visit London Reclaim Co. in London.
  2. 2Reserve the lot in writing with a deposit; get the batch/reference (L0430) and condition grade (7/10) on the receipt.
  3. 3Arrange transport: car/van accessible, assistance with loading provided. Confirm access at your delivery address (width, overhead clearance, forklift or hand-ball).
  4. 4On arrival, check the count against the 30 packs · ≈90m² stated and photograph any transit damage before signing the delivery note.
  5. 5Store correctly on site — for insulation, that means dry, level and off the ground; keep original packaging on until the day of use where possible.
  6. 6Dry-lay or trial-fit a small sample first to confirm insulation performs as expected in your specific application before committing the whole lot.
  7. 7Log the reuse for your project records: photograph the seller invoice, capture the ~60 kg CO₂e figure and save this listing URL in your embodied-carbon file.

Pre-purchase checklist

  • Measure twice — confirm 30 packs · ≈90m² covers your net requirement plus a 7% waste/cutting allowance.
  • View in person or request a video walkround from London Reclaim Co.; do not rely on the hero photograph alone.
  • Check condition against the 7/10 grade above — ask which specific defects apply to the units you'll actually receive.
  • Confirm the batch or shade reference (L0430) so what you inspect is what you collect.
  • Agree collection or delivery cost in writing — pallet, hiab, flatbed or hand-ball each price very differently.
  • Verify VAT position: is the £455/lot figure ex-VAT or inclusive? Trade sellers default to ex-VAT.
  • Ask about returns or replacements if the delivered quantity falls short — reputable demolitions stand behind the stated count.
  • Screenshot this listing (title, price, condition, CO₂ figure) as your negotiation baseline — surplus prices drift as lots age.
  • Check compatibility if you're matching existing material (brick blend, tile shade, timber section) with a physical sample first.
  • Book collection or delivery within your reservation window — reclaimed lots at this price rarely sit for long.

Price in context

  • At £455/lot, this lot sits roughly 39% below current UK merchant list for equivalent new material — the typical spread for reclaimed insulation.
  • Delivered-to-door pricing (including pallet freight within ~74 miles of London) tends to add £90–£150 to the headline figure; collection stays as advertised.
  • Comparable reclaimed lots in the surplus insulation & plasterboard category have moved on SurplusBuilder within 4 days of listing — well-priced surplus doesn't linger.

Sustainability deep-dive

The headline saving on this listing (~60 kg CO₂e) is benchmarked against producing virgin PIR/mineral wool boards (PIR ~3.5 kg CO₂e per m² at 100mm). That's the embodied-carbon figure — the emissions locked into new material at the point of manufacture, before it ever reaches your site.

In UK building terms, embodied carbon typically accounts for 40–60% of a project's whole-life emissions once operational energy is decarbonised. Reusing insulation like this lot from London bypasses the manufacturing stage entirely, which is why substitution consistently outperforms offsetting on lifecycle assessments.

For projects tracking against Part Z (the proposed embodied-carbon amendment to the Building Regulations), BREEAM Mat 01 credits, or the RIBA 2030 Climate Challenge, reused material counts at zero embodied carbon in the A1–A3 modules. Keep the seller invoice, this listing URL and the CO₂e figure together in your carbon file.

Beyond carbon: buying this lot from London Reclaim Co. keeps first-quality insulation out of the UK construction waste stream (currently ~62 million tonnes/year, per DEFRA). It supports the circular-economy supply chain — sellers who divert stock only continue diverting when there's a viable resale route.

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.

What payment and paperwork should I expect from London Reclaim Co.?+

London Reclaim Co. issues a VAT invoice on collection or dispatch — bank transfer is standard, card on request. For anything over £500 we recommend a written spec confirmation before paying, so the exact insulation description and quantity are on record.

Can I reserve this lot while I organise transport from London?+

A short reservation (typically 48–72 hours) is usually possible with a 10% holding deposit. Surplus stock moves quickly, especially reclaimed lots at this price point — confirm the hold in writing so the seller doesn't re-list.

Is this suitable for a Part L / Part Z reporting project?+

Yes — the ~60 kg CO₂e saving is calculable against the benchmark in the sustainability notes above; keep this listing URL as evidence for your embodied-carbon log.

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