Collection: Retrofit

Our expertise lies in providing advanced Retrofit solutions for both internal and external wall insulation, ensuring your home stays cosy while saving you money on energy bills.

With our wide range of wood fibre insulation, you can rely on year-round comfort. It keeps your house warm during chilly winters and pleasantly cool throughout the summer months.

Choose Insulation Merchant for a more comfortable, energy-efficient home that you'll love living in!

Retrofit Insulation | Insulation Merchant

Showing 118 of 118 products

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Showing 118 of 118 products

Showing 118 of 118 products
  • 80m Pro Clima Duplex Double Sided Membrane Tape
    Sale
    DUPLEX by Pro Clima

    80m Pro Clima Duplex Double Sided Membrane Tape

    Regular price
    £26.30 per item
    Unit Price
    £0.32 per LM (linear metre)
    inc. VAT
    Ex-Vat Price
    £21.92 per item
    Unit Price
    £0.27 per LM (linear metre)
    ex. VAT
    Regular price
    £27.00 Save £0.70
    Sale price
    £26.30 per item
    Unit Price
    £0.32 per LM (linear metre)
    inc. VAT
    Regular price
    £22.50 Save £0.58
    Ex-VAT Price
    £21.92 per item
    Unit Price
    £0.27 per LM (linear metre)
    ex. VAT
  • 25mm SKANDA Savolit Plus Wood Wool Board - 1200 x 600mm
    SAVOLIT PLUS - 1200MM by Skanda Savolit

    25mm SKANDA Savolit Plus Wood Wool Board - 1200 x 600mm

    Regular price
    £12.49 per item
    Unit Price
    £17.35 per m²
    inc. VAT
    Ex-Vat Price
    £10.41 per item
    Unit Price
    £14.46 per m²
    ex. VAT
    Regular price
    Save £-12.49
    Sale price
    £12.49 per item
    Unit Price
    £17.35 per m²
    inc. VAT
    Regular price
    £0.00 Save £-10.41
    Ex-VAT Price
    £10.41 per item
    Unit Price
    £14.46 per m²
    ex. VAT
  • STEICO Therm SD (wet)
    New
    THERM SD (WET) by Steico

    STEICO Therm SD (wet)

    Regular price
    From £5.62 per item
    Unit Price
    £6.94 per m²
    inc. VAT
    Ex-Vat Price
    From £4.68 per item
    Unit Price
    £5.78 per m²
    ex. VAT
    Regular price
    £5.04 Save £-0.58
    Sale price
    From £5.62 per item
    Unit Price
    £6.94 per m²
    inc. VAT
    Regular price
    £4.20 Save £-0.48
    Ex-VAT Price
    From £4.68 per item
    Unit Price
    £5.78 per m²
    ex. VAT
  • 75mm Thermafleece CosyWool Sheep Wool (2 x 570mm rolls)
    COSYWOOL by Thermafleece

    75mm Thermafleece CosyWool Sheep Wool (2 x 570mm rolls)

    Regular price
    £97.40 per item
    Unit Price
    £10.05 per m²
    inc. VAT
    Ex-Vat Price
    £81.17 per item
    Unit Price
    £8.38 per m²
    ex. VAT
    Regular price
    Save £-97.40
    Sale price
    £97.40 per item
    Unit Price
    £10.05 per m²
    inc. VAT
    Regular price
    £0.00 Save £-81.17
    Ex-VAT Price
    £81.17 per item
    Unit Price
    £8.38 per m²
    ex. VAT
  • ADAPTAVATE breathAplasta Thermal (Insulating Breathable Plaster) - 9kg bag
    THERMAL by Adaptavate

    ADAPTAVATE breathAplasta Thermal (Insulating Breathable Plaster) - 9kg bag

    Regular price
    £23.94 per item
    Unit Price
    £23.94 per m²
    inc. VAT
    Ex-Vat Price
    £19.95 per item
    Unit Price
    £19.95 per m²
    ex. VAT
    Regular price
    £23.10 Save £-0.84
    Sale price
    £23.94 per item
    Unit Price
    £23.94 per m²
    inc. VAT
    Regular price
    £19.25 Save £-0.70
    Ex-VAT Price
    £19.95 per item
    Unit Price
    £19.95 per m²
    ex. VAT
  • CEWOOD Wood Wool Multi-purpose Board - Square Edge
    Sale 5%
    MULTI-PURPOSE by Cewood

    CEWOOD Wood Wool Multi-purpose Board - Square Edge

    Regular price
    From £9.49 per item
    Unit Price
    £13.18 per m²
    inc. VAT
    Ex-Vat Price
    From £7.91 per item
    Unit Price
    £10.98 per m²
    ex. VAT
    Regular price
    £9.99 Save £0.50
    Sale price
    From £9.49 per item
    Unit Price
    £13.18 per m²
    inc. VAT
    Regular price
    £8.33 Save £0.42
    Ex-VAT Price
    From £7.91 per item
    Unit Price
    £10.98 per m²
    ex. VAT
  • 140mm Thermafleece CosyWool Sheep Wool (3 x 370mm rolls)
    COSYWOOL by Thermafleece

    140mm Thermafleece CosyWool Sheep Wool (3 x 370mm rolls)

    Regular price
    £96.10 per item
    Unit Price
    £18.81 per m²
    inc. VAT
    Ex-Vat Price
    £80.08 per item
    Unit Price
    £15.67 per m²
    ex. VAT
    Regular price
    Save £-96.10
    Sale price
    £96.10 per item
    Unit Price
    £18.81 per m²
    inc. VAT
    Regular price
    £0.00 Save £-80.08
    Ex-VAT Price
    £80.08 per item
    Unit Price
    £15.67 per m²
    ex. VAT
  • 40mm STEICO Therm (wet) - 600mm x 1350mm - per board
  • SIGA Majrex® 200 (1-directional) Airtight Humidity Vapour Control Layer - 1.5 x 50m (75m²)
    MAJREX® by SIGA

    SIGA Majrex® 200 (1-directional) Airtight Humidity Vapour Control Layer - 1.5 x 50m (75m²)

    Regular price
    £380.90 per item
    Unit Price
    £5.07 per m²
    inc. VAT
    Ex-Vat Price
    £317.42 per item
    Unit Price
    £4.23 per m²
    ex. VAT
    Regular price
    Save £-380.90
    Sale price
    £380.90 per item
    Unit Price
    £5.07 per m²
    inc. VAT
    Regular price
    £0.00 Save £-317.42
    Ex-VAT Price
    £317.42 per item
    Unit Price
    £4.23 per m²
    ex. VAT
  • SIGA Majcoat® 200 SOB Diffusion Open Roof Breather Membrane - 1.5m x 50m
    MAJCOAT® by SIGA

    SIGA Majcoat® 200 SOB Diffusion Open Roof Breather Membrane - 1.5m x 50m

    Regular price
    £317.65 per item
    Unit Price
    £4.23 per m²
    inc. VAT
    Ex-Vat Price
    £264.71 per item
    Unit Price
    £3.53 per m²
    ex. VAT
    Regular price
    Save £-317.65
    Sale price
    £317.65 per item
    Unit Price
    £4.23 per m²
    inc. VAT
    Regular price
    £0.00 Save £-264.71
    Ex-VAT Price
    £264.71 per item
    Unit Price
    £3.53 per m²
    ex. VAT
  • PROCTOR Spacetherm® A1 Fire Rated Silica Aerogel Blanket - 2400mm x 1200mm (2.88m²)
    SPACETHERM® by A. Proctor Group

    PROCTOR Spacetherm® A1 Fire Rated Silica Aerogel Blanket - 2400mm x 1200mm (2.88m²)

    Regular price
    From £240.61 per item
    Unit Price
    £83.55 per m²
    inc. VAT
    Ex-Vat Price
    From £200.51 per item
    Unit Price
    £69.62 per m²
    ex. VAT
    Regular price
    Save £-240.61
    Sale price
    From £240.61 per item
    Unit Price
    £83.55 per m²
    inc. VAT
    Regular price
    £0.00 Save £-200.51
    Ex-VAT Price
    From £200.51 per item
    Unit Price
    £69.62 per m²
    ex. VAT
  • 40mm STEICOduo Dry - 600mm x 2230mm
  • SIGA Majpell® 5 Vapour Control Layer - 1.5 x 50m (75m²)
    MAJPELL® by SIGA

    SIGA Majpell® 5 Vapour Control Layer - 1.5 x 50m (75m²)

    Regular price
    £233.70 per item
    Unit Price
    £3.11 per m²
    inc. VAT
    Ex-Vat Price
    £194.75 per item
    Unit Price
    £2.60 per m²
    ex. VAT
    Regular price
    Save £-233.70
    Sale price
    £233.70 per item
    Unit Price
    £3.11 per m²
    inc. VAT
    Regular price
    £0.00 Save £-194.75
    Ex-VAT Price
    £194.75 per item
    Unit Price
    £2.60 per m²
    ex. VAT
  • ULTIMATE Value Wood Wool Building Board
    Sale 5%
    BUILDING BOARD by Cewood

    ULTIMATE Value Wood Wool Building Board

    Regular price
    From £7.55 per item
    Unit Price
    £10.49 per m²
    inc. VAT
    Ex-Vat Price
    From £6.29 per item
    Unit Price
    £8.74 per m²
    ex. VAT
    Regular price
    £7.95 Save £0.40
    Sale price
    From £7.55 per item
    Unit Price
    £10.49 per m²
    inc. VAT
    Regular price
    £6.63 Save £0.33
    Ex-VAT Price
    From £6.29 per item
    Unit Price
    £8.74 per m²
    ex. VAT
  • 25mm SKANDA Savolit Plus Wood Wool Board - 2400 x 600mm
    SAVOLIT PLUS - 2400MM by Skanda Savolit

    25mm SKANDA Savolit Plus Wood Wool Board - 2400 x 600mm

    Regular price
    £24.90 per item
    Unit Price
    £17.29 per m²
    inc. VAT
    Ex-Vat Price
    £20.75 per item
    Unit Price
    £14.41 per m²
    ex. VAT
    Regular price
    Save £-24.90
    Sale price
    £24.90 per item
    Unit Price
    £17.29 per m²
    inc. VAT
    Regular price
    £0.00 Save £-20.75
    Ex-VAT Price
    £20.75 per item
    Unit Price
    £14.41 per m²
    ex. VAT
  • 140mm Thermafleece CosyWool Sheep Wool (2 x 570mm rolls)
    COSYWOOL by Thermafleece

    140mm Thermafleece CosyWool Sheep Wool (2 x 570mm rolls)

    Regular price
    £98.50 per item
    Unit Price
    £18.80 per m²
    inc. VAT
    Ex-Vat Price
    £82.08 per item
    Unit Price
    £15.66 per m²
    ex. VAT
    Regular price
    Save £-98.50
    Sale price
    £98.50 per item
    Unit Price
    £18.80 per m²
    inc. VAT
    Regular price
    £0.00 Save £-82.08
    Ex-VAT Price
    £82.08 per item
    Unit Price
    £15.66 per m²
    ex. VAT
  • SIGA Fentrim® grommet (White) - Internal Airtight Cable & Pipe Sealing
    FENTRIM® by SIGA

    SIGA Fentrim® grommet (White) - Internal Airtight Cable & Pipe Sealing

    Regular price
    From £4.30 per item
    inc. VAT
    Ex-Vat Price
    From £3.58 per item
    ex. VAT
    Regular price
    Save £-4.30
    Sale price
    From £4.30 per item
    inc. VAT
    Regular price
    £0.00 Save £-3.58
    Ex-VAT Price
    From £3.58 per item
    ex. VAT
  • Pro Clima Contega Solido SL-D80 (External Double-sIded Corner Adhesive Tape) - 80mm x 30m
    Sale
    CONTEGA SOLIDO SL-D by Pro Clima

    Pro Clima Contega Solido SL-D80 (External Double-sIded Corner Adhesive Tape) - 80mm x 30m

    Regular price
    £66.40 per item
    Unit Price
    £2.21 per LM (linear metre)
    inc. VAT
    Ex-Vat Price
    £55.33 per item
    Unit Price
    £1.84 per LM (linear metre)
    ex. VAT
    Regular price
    £68.16 Save £1.76
    Sale price
    £66.40 per item
    Unit Price
    £2.21 per LM (linear metre)
    inc. VAT
    Regular price
    £56.80 Save £1.47
    Ex-VAT Price
    £55.33 per item
    Unit Price
    £1.84 per LM (linear metre)
    ex. VAT
  • 115mm EJOT ejotherm STR U 2G Masonry Screw in Anchors (Box of 100)
    Sale 9%
    SCREW + WASHER by EJOT

    115mm EJOT ejotherm STR U 2G Masonry Screw in Anchors (Box of 100)

    Regular price
    £39.06 per item
    Unit Price
    £0.39 per screws
    inc. VAT
    Ex-Vat Price
    £32.55 per item
    Unit Price
    £0.33 per screws
    ex. VAT
    Regular price
    £42.97 Save £3.91
    Sale price
    £39.06 per item
    Unit Price
    £0.39 per screws
    inc. VAT
    Regular price
    £35.81 Save £3.26
    Ex-VAT Price
    £32.55 per item
    Unit Price
    £0.33 per screws
    ex. VAT
  • SIGA Fentrim® grommet (Black) - External Airtight Cable & Pipe Sealing
    FENTRIM® by SIGA

    SIGA Fentrim® grommet (Black) - External Airtight Cable & Pipe Sealing

    Regular price
    From £4.30 per item
    inc. VAT
    Ex-Vat Price
    From £3.58 per item
    ex. VAT
    Regular price
    Save £-4.30
    Sale price
    From £4.30 per item
    inc. VAT
    Regular price
    £0.00 Save £-3.58
    Ex-VAT Price
    From £3.58 per item
    ex. VAT