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The Fibreglass Supplies 2-Part Polyurethane Expanding Foam Kit is a versatile, two-part (Part A & Part B), liquid foam system designed for projects that require a lightweight, rigid, and highly buoyant foam. When mixed in equal parts, this foam expands up to 25 times its original liquid volume, curing into a strong closed-cell structure that is both waterproof and durable. Ideal for marine, construction, insulation and moulding applications, it provides dependable performance where strength and buoyancy are essential.
This expanding foam is exceptionally buoyant - just 1 cubic foot of cured foam can support 27kg in water. Once set, it bonds well to most materials, creating a rigid and stable form that enhances structural integrity. It is commonly used in boat building, floatation devices, cavity filling, and lightweight construction projects.
Supplied as a two-part liquid, the foam is simple to use: just combine both parts in equal measure, pour, and allow it to expand. At standard room temperature (18°C), 1kg of liquid foam produces 1 cubic foot of solid expanded foam. Expansion may be reduced at lower temperatures, so correct working conditions ensure maximum yield.
Protective Requirements: While the foam sets as a closed-cell, waterproof structure, it should always be protected with a GRP (glass reinforced plastic) skin. This prevents water ingress if the foam is crushed, ensuring long-term durability in marine and outdoor environments.
Customer Reviews4.55 4.5/5 Based on 2 reviews
Easy to useReviewed by Doug on 30 Mar 2025
Easy to use foam. Fast acting. I tested small amounts first and achieved around 16x expansion by warming the foam to 20 degrees C, aerating part A as suggested in the directions, and ensuring that the room and surfaces were around 18-20 degrees. Could not get the "up to 25x" described on the tine but this was my first time using 2-part foam so perhaps it would improve with practice.
top gearReviewed by Tonymurton on 25 Feb 2025
Easy to mix and use
Fibreglass Supplies use Royal Mail, APC Overnight and the National Hazardous Pallet Network for our Next Day Delivery Services.
Royal Mail
Orders of up to 2kg will usually be sent using a Royal Mail First Class Service for National Next Day Delivery.
APC Overnight
Orders over 2kg and up to 30kg will be sent using a Fully Tracked Next Day Service using APC Overnight. Some smaller Roofing Kits that weigh up to 30kg in Total would be sent on this service. This includes Resins, Gelcoats and Topcoats which are classed as Hazardous and are decanted into 5kg Tins or Pales to comply with the Transportation of Hazardous Goods Act.
Pallet Network
All our larger orders by weight would usually be sent using the National Pallet Network. Non Hazardous Items can be sent using either the Pallet Network or APC Overnight.
All Hazardous goods over 30kg (which includes Roofing Kits over 30kg in total weight) are usually sent using the National Pallet Network on a Fully Trackable Next Day Delivery Service.
Click & Collect
All orders are eligible for Click & Collect. Pick up your items conveniently from our Cattedown Store, available Monday to Friday between 7:30 am and 4:30 pm (excluding Bank Holidays).
NB - Please note that our Direct Control of the Delivery Element extends to making sure we pick pack and dispatch all orders on time. As we have no Direct Control over the performance of any individual courier we would not be responsible for refunds due to the late arrival of any order.
We always work hard with customers to overcome any issues that arise so please call us if you do have any concerns with regard to tight delivery deadlines so that we can provide great advice if needed.
Please read our Returns policy laid out below.
Under the Consumer Contracts Regulations 2014 you are entitled to return goods within 14 days of delivery for a refund of the cost of the goods. The delivery costs and any packaging are not included in the refund. The returned goods should be in the original containers and unopened. It is the customers responsibility to pay for the cost of returning goods to our Business Premises.
Some of our products are made to order and as such once ordered are non refundable and non returnable. These include coloured gelcoats, topcoats and resins.
These Consumer Regulations do not apply to business purchases (B2B). However we will always help in any way and look to find a suitable and mutually acceptable solution should any issues arise through the order process.
It is the customers responsibility to understand the suitability of the product before its use. Technical and Safety Data Sheets are available for all products where applicable. These can be found on most product description pages or if not are available on request. If you are unsure please do not hesitate to contact us for expert advice and product suitability and application.
To organise a return please contact us on the following.