SKU: 58136002301

Thermaclass Cavity Wall 21 - 1190mm x 450mm

Sale price$101.00 Regular price$112.22
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Ships within 48 hours · Estimated delivery Jul 25 - Jul 30

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Description

Thermaclass Cavity Wall 21 - 1190mm x 450mmThickness Sheets Per Pallet Sheet Coverage Pallet Coverage 90mm 96 0. 5355 m2 51. 4 m2 115mm 80 0. 5355 m2 42. 8 m2 140mm 64 0. 5355 m2 34. 2 m2 Thermaclass Cavity Wall 21 is an easy to install, high thermal performance polyisocyanurate (PIR) insulation board for full fill cavity wall applications, with a thermal conductivity of 0. 021 W m. K. It can be installed with up to a 10mm residual cavity (to support ease of installation and accommodate mortar

Thickness Sheets Per Pallet Sheet Coverage Pallet Coverage
90mm 96 0.5355 m2 51.4 m2
115mm 80 0.5355 m2 42.8 m2
140mm 64 0.5355 m2 34.2 m2

Thermaclass Cavity Wall 21 is an easy to install, high thermal performance polyisocyanurate (PIR) insulation board for full fill cavity wall applications, with a thermal conductivity of 0.021 W/m.K. It can be installed with up to a 10mm residual cavity (to support ease of installation and accommodate mortar squeeze) or as a full fill solution with no residual cavity.

The boards have a low emissivity foil facing to each side and feature an engineered tongue and groove joint profile, helping to ensure a continuous layer of insulation to maximise thermal performance and provide protection from wind driven rain.

Product Features

  • Lightweight 1190 x 450mm boards (installed dimensions)
  • Tongue and groove edge profile
  • Low emissivity foil facing
  • BBA approved – certificate 16/5343

Product Properties

  • Board size: 1190 x 450mm (installed) 1205 x 465mm (including tongue)
  • Thickness : 90-140mm
  • Material: PIR

Product Performance

  • Lambda: 0.021 W/m.K
  • Reaction to Fire: Euroclass E Reaction to Fire classification, according to EN 13501-1 (Products with this level of classification are not provided with a rating for smoke emission)

Product Benefits

  • Excellent thermal performance with a thermal conductivity of 0.021 W/m.K, reducing the thickness of insulation required to hit the target U-value.
  • Low emissivity foil facing provides improved thermal performance in sealed cavity air spaces, improving the achievable U-value.
  • Easy to install – The boards are sized to fit standard cavity wall tie spacing. They are light and rigid, assisting with ease of transportation, handling and fitting.
  • BBA certified - Thermaclass Cavity Wall 21 has been assessed by the BBA as fit for use in defined full fill cavity wall applications if installed, used and maintained as set out in the certificate.

Applications

  • External Walls – full fill cavity wall

Key Considerations

Thermaclass Cavity Wall 21 should not be used in the external walls of buildings over 18 metres in height (England and Wales) or 11 metres in height (Scotland). Recent changes to Building Regulations mean that only non-combustible insulation or insulation of limited combustibility can be used in buildings of that height.

Shipping Notes
  • Free Standard Shipping on $100+ Orders to the USA.
  • Except Preorder products are shipped in 48 hours.
  • Delivery to the USA:
  1. Standard Shipping : 3-10 business days
  • If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
  • We offer a 30-day return/exchange service after receiving.
  • Final sale items are not eligible for returns or exchanges.
  • To process your return/exchange, please contact us at [email protected]
  • Please click here for more details>>> Return & Exchange Policy
SKU: 58136002301

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BETTY HILDRETH
Boise, US
★★★★★ 5
very stylish
Size: Medium, Color: Pure Apricot
true to size. very comfortable.
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Reviewed in the United States on June 1, 2026
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Cap47
Fort Morgan, US
★★★★★ 5
Great Material
Love the sweater. So soft.
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Reviewed in the United States on May 23, 2026
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Eden Fam
Lexington, US
★★★★★ 5
LOVE. Ordering more colors.
Size: Medium, Color: Porpoise, Size: Medium, Color: Porpoise
I absolutely LOVE this sweater. This sweater is so flattering and comfortable. Great quality and the material is cozy and soft. I will be ordering this in more colors for sure! I just got it today but I know this will be my go to this season for lounging as well as being out and about. It could easily be dressed up or down and I love the Porpoise color I got (see photos). Originally I thought this came in a set but I still thinks its worth the price for just the sweater and I plan to order the shorts anyway. I got the medium and it fit true to size and so flattering. I am 5ft 2 and about 140lbs being heavier in my legs/hips. I generally wear a small/medium on top depending on the style and a large/XL on bottom. Definitely will be getting more colors!!
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Reviewed in the United States on December 1, 2023
D
Verified Purchase
Diane B
Alexandria, US
★★★★★ 5
beautiful Perfect Sweater! Highly Recommend!
Size: 3X, Color: Zephyr Pink
Gorgeous color. Soft and snuggly. Cool enough in summer for office wear. My office sometimes gets cold even in the summer and this sweater is perfect. I wear it with brown slacks and it looks very professional but could be dressed down for casual affairs. The cut is generous and maybe even runs a little large however, I like the loose fit. I still can't get over the neutral pink color. It is just amazing and was a real steal as it was on sale when I ordered it!
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Reviewed in the United States on June 22, 2025
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Dani Cuervo
Cuba, US
★★★★★ 4
Stylish and comfortable
Size: 3X, Color: Porpoise
I love the slit in the back, it elevates the sweater well. It’s comfortable and made out of a thick, quality material. The only downside is that the sleeves are quite long and don’t roll up well. Otherwise I love it!
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Reviewed in the United States on March 18, 2026

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