90mm Mannok IsoCavity Full Fill Cavity Wall Insulation
1200mm x 450mm | 2.16m² per pack
FREE delivery over £500 excluding VAT
90mm Mannok IsoCavity Full Fill Cavity Wall Insulation
1200mm x 450mm | 2.16m² per pack
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FREE delivery over £500 excluding VAT
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Product Description
Product Description
90mm Mannok IsoCavity Full Fill Cavity Wall Insulation is a rigid PIR insulation board manufactured for masonry cavity walls, where it fills the cavity rather than leaving the wide residual gap a partial fill board demands. It is the entry thickness in the IsoCavity range, sized to suit a standard 100mm cavity, and it replaces Mannok's earlier IsoShield board with a foil facing designed to be easier to handle on site.
Each board measures 1200mm x 450mm x 90mm, covering 0.54m² per board, and is supplied in a pack of 4 boards covering 2.16m² per pack. The board has a thermal conductivity of 0.022 W/mK and a thermal resistance of 4.05 m²K/W*, with a compressive strength greater than 140 kPa and a core water vapour resistivity of 300 MNs/gm. Dimensional stability is classified DS(TH)4 to EN 1604, so boards hold their shape and butt tightly to form a continuous insulation layer.
Both faces carry a low emissivity composite foil, which raises the thermal resistance of the residual cavity alongside the insulation value of the core itself. The four tongue and groove edges are precision cut so boards interlock as they are placed, helping maintain continuity of insulation across every joint and restricting moisture movement through the joint line. Because the profile does the alignment for you, boards go in square and stay square as the inner leaf is built up.
Mannok IsoCavity is used in masonry cavity wall construction and has been tested and certified for a residual cavity of 0mm to 10mm, which is what allows a 90mm board to work in a 100mm cavity. For cavities up to 100mm, Mannok specify wall ties in the inner leaf at maximum 900mm horizontal and 450mm vertical centres, with additional ties at openings and corners, and boards fitted tight against the inner leaf with joints tightly interlocked. Install in line with the latest Mannok technical guidance, the project specification and the relevant Building Regulations. Filling the cavity this way lifts the thermal performance of the wall without adding to its overall thickness, which matters when the footprint and the outer leaf position are already set.
Key Benefits of 90mm Mannok IsoCavity:
- 90mm rigid PIR full fill cavity board sized to suit a standard 100mm masonry cavity.
- Thermal conductivity of 0.022 W/mK, among the lowest available from rigid board insulation.
- Thermal resistance of 4.05 m²K/W* for the 90mm board.
- Tested and certified for a residual cavity of 0mm to 10mm, so more of the cavity width does useful work.
- Precision cut tongue and groove edges on all four sides for continuity of insulation across joints.
- Low emissivity composite foil facings on both faces, increasing the thermal resistance of the residual cavity.
- Compressive strength greater than 140 kPa.
- DS(TH)4 dimensional stability to EN 1604, allowing boards to be tightly butted into a continuous layer.
- Zero ozone depletion potential and a global warming potential of less than 5.
- Fibre free, rot resistant, and does not support mould or fungus.
- Supplied as 4 boards per pack covering 2.16m².
Good to Know:
- Cavity sizing: the IsoCavity range is built around standard cavity widths, with 90mm for a 100mm cavity, 115mm for 125mm and 140mm for 150mm.
- Foil facing: the low emissivity foil is a thermal facing. It is not a vapour control layer and does not replace one where the design calls for it.
- Fire performance: reaction to fire is Euroclass F to BS EN 13501-1, which should be checked against the fire strategy for the building.
- Keep the cavity clean as you build. Mortar droppings on the block face stop boards seating properly against the inner leaf.
- Wall insulation should extend 150mm below the upper edge of floor insulation to limit thermal bridging at the floor perimeter.
- Mannok provide U-value and interstitial condensation calculations for specific wall build-ups through their technical team.
For a standard cavity built to a modern specification, the 90mm board is the one that does the most with the width you already have.
Certifications & Standards
Certifications & Standards
Technical Datasheets
Technical Datasheets
- Mannok Isocavity Fullfill Wall Cavity Technical Data Sheet
- Mannok Isocavity Fullfill Wall Cavity Safety Data Sheet
- Mannok Isocavity Fullfill Wall Cavity Installation Guide
- Mannok Isocavity Fullfill Wall Cavity Declaration of Performance
- Mannok Isocavity Fullfill Wall Cavity Flyer
- Mannok Isocavity Fullfill Wall Cavity KIWA Certificate
- Mannok Isocavity Fullfill Wall Cavity ISO9001 Certificate
- Mannok Isocavity Fullfill Wall Cavity 14001 Certificate
- Mannok Isocavity Fullfill Wall Cavity 50001 Certificate
Customer Information
Customer Information
Free delivery on orders over £500 ex-VAT. All orders below £500 (ex-VAT) are subject to a £50 delivery charge.
Ordering & Delivery
How do I place an order with Insulation UK?
You can place an order for delivery anytime online. If you want to collect from our distribution centre in South Yorkshire then please email us your requirements at sales@insulationuk.co.uk
and we will send a payment link and collection instructions. If you can’t see what you are looking for or need more information, then call our team on 03003 034 578 and we can sort your order from there.
How do I know what’s happening with my order and when I will receive it?
When you have placed your order, you will then receive an email confirmation, giving you an order reference number and asking you to double check everything is correct on your order such as delivery address, quantities etc. If there are any amendments to be made, then please reply to your confirmation email with any details.
Once the team has processed the order you will receive an email with a BY delivery date, this is the latest date you will receive your delivery.
Your final email will be a 24/48hr notification, on the day of the delivery if you need a more accurate ETA then contact the office on 03003 034 578.
Do you offer next-day delivery?
Yes, we do on certain lines, you will see our next day delivery products marked as NEXT DAY. Order before 12pm for next day delivery (charges will apply)
How much does delivery cost and how long will it take?
Standard delivery is £50 + VAT for all orders below £500 excluding VAT, above £500 excluding VAT delivery is free. Bespoke deliveries can be made but will incur charges. Each product page gives you an estimate delivery by date. For more accurate information call the team on 03003 034 578
Can I choose a specific delivery date or time slot?
We will endeavour to try and accommodate a preferred date, if you need a delivery on a certain day, then please call us on 03003 034 578.
Do you deliver nationwide?
We deliver across most of the UK; however, some postcodes are restricted due to their location. Check out our delivery map for more information. If you find that you are in area we don’t deliver to, we have access to a wide range of haulage options, please call the team on 03003 034 578 to discuss your requirements further.
Will the driver help unload the insulation products?
Most of our deliveries are made with vehicles with mechanical off-load (known as a moffett or fork-lift), the driver will leave them in a safe place of your choice. They will help as much as they are allowed but are not insured to bring anything into a property.
What happens if my order arrives damaged or incomplete?
In the unlikely event your order arrives damaged, then please contact within 48 hours at sales@insulationuk.co.uk with any images of the damage and the team will be in touch. If there is anything missing, then notify the team within 48 hours on 03003 034 578
What if my order doesn’t arrive and I have paid for trades to be on site, can I claim anything towards the costs I have incurred?
We advise not to have trades booked in and around the day of your delivery. Things can happen beyond our control, and your delivery may be delayed or abandoned. We cannot be held liable for any consequential loss such as tradesman wages etc.
Product Advice & Support
How do I know which insulation product is right for my project?
With such a variety of insulation products, we fully understand making sure you have the right one can seem daunting. Our team have over 50 years of experience in the construction industry and there isn’t a question they haven’t been asked! Speak to our technical team on 03003 034 578 and they will be happy to offer some help and guidance.
Do you offer technical advice or support before I buy?
Yes we do! Just call 03003 034 578 and ask for our technical team and we will be happy to support you.
Product Information & Suitability
Product descriptions on this website are provided as general guidance only and are not a substitute for the manufacturer’s Technical Data Sheet (TDS), fire classification information, and the project’s design/specification requirements. Suitability depends on the full build-up and intended use (including any requirement for encapsulation, coverings, and compliance with Building Regulations and the project fire strategy).
It is the customer’s responsibility to confirm, before ordering, that the product specification and performance are suitable for the intended application by reviewing the relevant TDS and taking professional advice where required. If you are unsure, contact us before purchase and provide your intended build-up so we can confirm what information we can support.
Nothing in this notice limits or excludes your statutory rights
Can I speak to someone to confirm product specifications?
Of course you can! There is also a range of data sheets and guides available on the product pages under Technical Information.
Are your products suitable for both DIY and trade customers?
Yes, they are. If you are new to DIY projects involving insulation,
then we advise to always do your research. We have a handy guides section which may help.
Do you offer fire-rated or eco-friendly insulation options?
Yes, we do. Fire ratings are indicated in the specification table on the product page, and our sustainable range is continually growing.
Pricing & Payments
Do you offer trade or bulk-buy discounts?
We always aim to offer the best price online; however we do offer project pricing for larger orders, speak to our sales team with your requirements on 03003 034 578.
What payment methods do you accept?
We accept all major cards including American Express, as well as Apple Pay, Google Pay and PayPal
Can I set up a trade account with credit terms?
We do offer trade accounts, however there are certain criteria we ask for, and any credit account application is subject to credit checks. Call the team on 03003 034 578 to discuss any credit applications.
Do your prices include VAT?
The website has a toggle at the top right of the page so the prices can be displayed including and excluding VAT. VAT, where applicable, is charged at checkout.
Returns & Cancellations
Can I return unwanted insulation products?
Contact the team via email sales@insulationuk.co.uk with the items you wish to return and any other information. Please note if we you need us to collect any unwanted items,
a collection fee will apply.
How do I arrange a return or exchange?
Contact the team via email sales@insulationuk.co.uk or check out our refund policy.
Are there any restocking fees?
Restocking charges will apply in certain instances, please contact the team via email at sales@insulationuk.co.uk check out our refund policy.
What if I’ve ordered incorrectly or need to cancel my order?
Contact the team via email as soon as possible. The best way to get in contact is to reply to any of the emails we have sent you, they will come straight through to the team and will have any relevant order information already on there.
Installation & Compliance
Do you offer installation services or just supply materials?
We do not offer any installation services; we are a supplier of insulation and building materials.
Can I get a datasheet or certificate of performance for your products?
Yes, data sheets can be found in the Technical Information drop down on the product page.
How should I store insulation products before installation?
There are a variety of insulation products each with their own storage instructions. Generally, please keep them off the ground, in a dry area, away from the elements.
Sustainability & Quality
Are your insulation products environmentally friendly?
This depends on the individual products, data sheets are available,
and any environmental benefits are noted on the product pages.
Do your products help reduce energy bills?
The correct insulation properly installed can reduce heat loss from a building and therefore help reduce energy costs.
Are your products made in the UK or imported?
With such a wide variety of products some are made in the UK and some are imported.
Customer Service & Support
How can I contact your support team?
By phone on 03003 034 578, email sales@insulationuk.co.uk or via our
webchat online
What are your opening hours?
Monday to Friday 8am to 5pm for sales and technical support, orders can be placed on line 24/7
How quickly can I expect a reply to my enquiry?
We aim to respond to our customers as quickly as possible.
Technical Details
- Brand:
- Mannok
- Material:
- Polyisocyanurate
- Size:
- 1200mm x 450mm x 90mm
- Length:
- 1200 mm
- Width:
- 450 mm
- Thickness:
- 90 mm
- Unit Coverage:
- 0.54 m²
- Qty Per Pack:
- 4 Items
- Sqm Per Pack:
- 2.16 m²
- Applications:
- Wall
- Edge Type:
- Tongue and Groove
Thermal performance helps show how effectively the product reduces heat transfer.
Thermal conductivity measures how readily heat passes through the material, so lower figures generally indicate better insulating performance.
R Value shows the material’s thermal resistance at that thickness, so higher figures generally mean stronger insulation performance.
These figures relate to the insulation product itself and should be considered alongside the full wall, roof or floor build-up when checking project requirements.
- Thermal Conductivity:
- 0.022 W/mK
Compressive strength shows how well a product resists being squashed under pressure.
The figure is measured in kPa, which stands for kilopascals.
A higher kPa number means stronger resistance to compression. For example, 120 kPa offers more compression resistance than 70 kPa, but less than 150 kPa, 200 kPa or 300 kPa.
This does not mean the product can carry that load on its own. It should always be checked as part of the full floor, wall, roof or system build-up.
- Compressive Strength:
- >140 kPa
Euroclass reaction to fire is the European EN 13501-1 classification used to show how a construction product behaves when exposed to fire.
The main scale runs from A1 and A2 at the highest end, through B, C, D and E, down to F.
A1 is non-combustible and A2 is limited combustibility, while lower classes indicate a greater contribution to fire.
Euroclass F is the lowest rating on this scale and indicates the weakest reaction-to-fire performance.
This is different from fire resistance, which relates to how long a complete wall, floor or roof build-up can resist fire.
- Reaction to Fire:
- Euroclass F to BS EN 13501-1
