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115mm Celotex Thermaclass Cavity Wall 21 Full Fill Insulation Board T&G 1190mm x 450mm (2.68m2/Pack)

115mm Celotex Thermaclass Cavity Wall 21 Full Fill Insulation Board T&G 1190mm x 450mm (2.68m2/Pack)

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£154.05
Sale price  £154.05 Regular price 
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    Description

    Product Overview

    Celotex Thermaclass Cavity Wall 21 Full Fill Insulation Board with a 115mm thickness and 1190mm × 450mm dimensions.
     
    High-performance rigid polyisocyanurate (PIR) insulation board designed for use in full fill masonry cavity wall applications. Manufactured with a low emissivity foil facing, it delivers exceptional thermal conductivity of 0.021 W/mK, helping achieve low U-values while reducing overall wall thickness requirements.

    The tongue and groove edge profile provides a tight, secure fit, minimising air gaps and thermal bridging. The board can be installed as a full fill solution or with a residual cavity of up to 10mm to accommodate mortar squeeze and simplify installation.

    Lightweight, rigid, and easy to handle, the board fits standard wall tie spacing, supporting fast, efficient on-site fitting. The 115mm thickness is ideal for deeper cavity walls in high-performance housing and commercial developments.

    Features & Benefits

    • Outstanding thermal performance: Declared thermal conductivity of 0.021 W/mK reduces wall thickness while achieving low U-values.
    • High performance facer: Low emissivity foil facing improves performance in cavities with up to 10mm air space.
    • Precision fit: Tongue and groove edge detail ensures close jointing and minimal thermal bridging.
    • Ease of installation: Sized for standard wall tie spacing; light, rigid boards are simple to transport and fit.
    • Certified performance: BBA certified for full fill cavity wall use under Certificate 16/5343.
    • Thickness: 115mm board ideal for deeper cavity walls in high-performance housing and commercial developments.


    Applications

    • Full fill cavity walls: Suitable for use between masonry leaves in domestic and commercial buildings.
    • New build housing: Provides excellent U-value compliance in energy-efficient walls.
    • Residual cavity installation: Can be fitted with a 10mm residual cavity to accommodate mortar squeeze.
    • Thermal upgrade projects: Ideal for meeting advanced energy performance requirements.


    Installation Guidance

    • Preparation: Ensure cavity surfaces are clean and free from debris before installation.
    • Board placement: Install boards with tongue and groove joints interlocked and staggered in brick bond pattern.
    • Fixing method: Secure with appropriate retaining clips to wall ties as construction progresses.
    • Joint sealing: Ensure tight-fitting joints with no gaps; seal edges as required by specification.
    • Residual cavity: Maintain up to 10mm air space where design requires.
    • Protection: Keep boards dry and covered until fully installed.


    Compliance & Performance

    • Material specification: Rigid PIR insulation with low emissivity foil facing.
    • Thermal conductivity: 0.021 W/m·K (to BS EN 13165).
    • Fire performance: Euroclass E reaction to fire to BS EN 13501-1.
    • Compressive strength: ≥120 kPa at 10% compression.
    • Water vapour resistance: High resistance due to foil facing.
    • Certification: BBA certified (No. 16/5343) for full fill cavity wall systems.
    • Environmental compliance: Manufactured under ISO 14001:2015 Environmental Management System.
    • Standards compliance: UKCA marked to BS EN 13165 for factory-made rigid polyurethane (PU) insulation.
    • Important note: Install and maintain in accordance with Celotex guidance and BBA certification details.


    Shipping Policy

    At Supply Yard UK, we are committed to providing a reliable, transparent, and efficient shipping experience for all our customers across the United Kingdom.

    Shipping Destination

    We currently ship exclusively within the United Kingdom (mainland). Orders placed for delivery outside the UK mainland cannot be processed.

    Shipping Cost

    Delivery charges depend on the product category and your order value. All charges are shown clearly in your basket and at checkout before you pay. Because building materials vary greatly in size and weight, different categories have different delivery rates.

    Product Category Order Value Standard Delivery Express Delivery
    Core / General Items Under £200 £15
    £200 and over Free
    Insulation, Plasterboard & Drylining Under £400 £45 £90
    £400 and over Free £55
    Timber, Building Materials, Joinery, Gardens & Roofing Under £300 £30 £50
    £300 and over Free £35
    Screws & Fixings, Adhesives & Sealants Under £75 £7.50
    £75 and over Free
    Facing Bricks Any order value £85 per pack
    Bulk Deals / Pallets Any order value £120 flat

     

    Orders containing products from different categories may show more than one delivery charge, as items can ship separately from different suppliers.

    Delivery Timeframes

    Detail Information
    Order Handling Time 0–1 business day (Monday–Friday)
    Order Cut-Off Time 2:00 PM GMT
    Standard Transit Time 3–5 business days (Monday–Friday)
    Express Transit Time 1–2 business days (Monday–Friday)
    Estimated Delivery Standard: 3–7 days incl. handling / Express: 1–3 days incl. handling

     

    Orders placed after 2:00 PM GMT or on weekends and UK public holidays will be processed on the next available business day.

    Please note that delivery times are estimates and are not guaranteed. Delays may occasionally occur due to severe weather, courier disruptions, public holidays, or other circumstances beyond our control.

    Carrier Services

    We dispatch orders using trusted UK courier and haulage services, including:

    • Royal Mail
    • Evri
    • FedEx
    • UPS
    • DHL
    • Palletised freight carriers (for heavy and bulk items)

    The carrier selected for your order will depend on the parcel's size, weight, and delivery destination. Larger building materials are delivered on pallets via specialist vehicles and are typically delivered kerbside.

    Order Tracking

    Once your order has been shipped, you will receive a dispatch confirmation email containing your tracking number. You can use this tracking number to monitor your shipment from dispatch through to delivery.

    Dispatch Days

    Orders are dispatched Monday through Friday only. Orders placed on weekends or UK public holidays will be processed on the next available business day.

    Failed Delivery Attempts

    If a delivery attempt is unsuccessful, the courier may leave a notification card, attempt redelivery, or make the parcel available for collection at a local depot, depending on the courier's policy.

    Customers are responsible for providing a complete and accurate delivery address at checkout. Supply Yard UK is not responsible for delays, failed deliveries, or additional shipping charges resulting from incorrect or incomplete address information.

    Lost or Delayed Parcels

    If your order has not arrived within the estimated delivery timeframe, please contact our customer support team. We will work directly with the courier to investigate and resolve the issue as quickly as possible.

    Contact Information:

    Store Name Supply Yard UK
    Company No. 16994235
    Registered Address 139a Cherry Orchard Road, Croydon, England, CR0 6BF, United Kingdom
    Email sales@supplyyard.co.uk
    Phone +44 (7446) 365-929
    Website https://supplyyard.co.uk
    Support Hours Monday to Friday, 9:00 AM – 5:00 PM GMT
    Response Time Our customer support team responds within 48 hours (on business days, Mon-Fri)

    Refund Policy

    At Supply Yard UK, we are committed to providing high-quality products and excellent customer service. We want you to be completely satisfied with your purchase. If for any reason you need to return an item, we have a clear and transparent return process to assist you.

    1. Return Window

    We offer a 28-calendar-day return window. This means you have 28 calendar days after receiving your item to request a return. If 28 calendar days have passed since your delivery, unfortunately we cannot offer you a refund or return under this policy.

    2. Eligibility for Returns

    To be eligible for a return, your item must be in the exact condition that you received it:

    It must be unused, uninstalled, and in its original packaging

    All tags, labels, and included accessories must be intact

    Your order confirmation or proof of purchase is required

    Items that have been cut, drilled, modified, installed, or altered after delivery are not eligible for return

    3. Damaged, or Incorrect Items

    If your item arrives damaged or incorrect, please contact us within 24 hours of delivery at sales@supplyyard.co.uk with clear photographic evidence of the issue. We will arrange a full refund or replacement and cover all return shipping costs. Claims submitted after 24 hours of delivery may not be eligible for a free return or full refund.

    4. Return Shipping Costs & Method

    To ensure complete transparency, here is how return shipping is handled:

    Damaged or Incorrect Items: Contact us within 24 hours of delivery with photographic evidence. We will arrange a full refund or replacement and cover all return shipping costs.

    Change of Mind Returns: If you ordered the wrong item or simply no longer want it, you are responsible for arranging and paying for the return shipping costs. We recommend using a tracked delivery service as we cannot accept responsibility for returned parcels lost in transit.

    We do not provide prepaid return shipping labels for change-of-mind returns.

    5. Restocking Fees

    We do not charge any restocking fees on returns.

    6. Order Cancellations

    Orders can be cancelled free of charge within 12 hours of placing them (Provided the order has not yet been dispatched). To cancel, contact us immediately at sales@supplyyard.co.uk with your order number. If the order has already been dispatched, please use our standard return process once you receive the item.

    7. Refund Processing

    We will notify you by email once we have received and inspected your returned item.

    Approval & Timeline: Approved refunds are processed within 14 calendar days of receiving and inspecting the returned item at our facility

    Payment Method: Refunds are issued to your original payment method only

    Delivery Charges: Original delivery charges are non-refundable unless the return is due to our error

    8. Exchanges

    Supply Yard UK does not offer direct exchanges. If you require a different product, please return your original purchase in accordance with this policy and place a new order through our website.

    9. Contact Information:

    Store Name Supply Yard UK
    Company No. 16994235
    Registered Address 139a Cherry Orchard Road, Croydon, England, CR0 6BF, United Kingdom
    Email sales@supplyyard.co.uk
    Phone +44 (7446) 365-929
    Website https://supplyyard.co.uk
    Support Hours Monday to Friday, 9:00 AM – 5:00 PM GMT
    Response Time Our customer support team responds within 48 hours (on business days, Mon-Fri)

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