---
product_id: 489776488
title: "6LB Density Expanding Pour Foam, 2 Part Polyurethane Closed Cell Liquid Foam for Boats, Dock Flotation, Carving, Soundproofing, Filling Voids, and Insulation (Quart Kit)"
brand: "fiberglass supply depot"
price: "£48.04"
currency: GBP
in_stock: true
reviews_count: 8
category: "Fiberglass Supply Depot"
url: https://www.desertcart.co.uk/products/489776488-6lb-density-expanding-pour-foam-2-part-polyurethane-closed-cell
store_origin: GB
region: United Kingdom
---

# 2-part polyurethane formula for precision mixing 5 min full cure time for rapid project turnaround 6LB density for max buoyancy & strength 6LB Density Expanding Pour Foam, 2 Part Polyurethane Closed Cell Liquid Foam for Boats, Dock Flotation, Carving, Soundproofing, Filling Voids, and Insulation (Quart Kit)

**Brand:** fiberglass supply depot
**Price:** £48.04
**Availability:** ✅ In Stock

## Summary

> 🚀 Expand your projects with foam that works as fast and smart as you do!

## Quick Answers

- **What is this?** 6LB Density Expanding Pour Foam, 2 Part Polyurethane Closed Cell Liquid Foam for Boats, Dock Flotation, Carving, Soundproofing, Filling Voids, and Insulation (Quart Kit) by fiberglass supply depot
- **How much does it cost?** £48.04 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.co.uk](https://www.desertcart.co.uk/products/489776488-6lb-density-expanding-pour-foam-2-part-polyurethane-closed-cell)

## Best For

- fiberglass supply depot enthusiasts

## Why This Product

- Trusted fiberglass supply depot brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Rapid 5-Minute Cure:** Get projects done fast with foam that fully sets in just 5 minutes
- • **Precision 2-Part Mix:** Equal parts A & B ensure consistent, reliable expansion every time
- • **High-Density Strength:** 6LB closed-cell foam delivers superior buoyancy and structural support
- • **Versatile Application:** Perfect for boats, docks, soundproofing, carving, and void filling
- • **Resin-Compatible Finish:** Can be laminated with polyester, epoxy, or vinyl ester without damage

## Overview

Fiberglass Supply Depot’s 6LB Density Expanding Pour Foam is a professional-grade, 2-part polyurethane closed-cell liquid foam designed for rapid curing and high-strength applications. Ideal for boat flotation, soundproofing, insulation, and sculpting, this 1-quart kit produces 0.375 cubic feet of durable foam that bonds seamlessly with common resins, enabling versatile, precision repairs and creative projects.

## Description

Product description

Review: Excellent Closed Cell Foam for Small Projects - This worked well to fill a small void in a fiberglass boat step project I was working on. I am not sure how waterproof it would have been because I encapsulated it with epoxy before covering it with glass and Coosa board. One thing I had trouble with was figuring out how much to mix for the size of void. That information was provided but I way over estimated how much was needed. It was easy enough to cut off the excess with a hack saw. The image attached is "after" I made the adjustment to closer to the right amount. Making that calculation easier for smaller quantities would be nice. Along those lines, markers on the bottles for smaller batches would be very helpful. Nice product though.
Review: Very good - just what I needed - This saved me having to rip out and re-mortar a tub. First time mortar bed for fiberglass acrylic tub and the mortar shrank leaving voids. This fills the voids perfectly, it’s incredibly solid now. In case you’re wondering as I was, this will go through a tube to get it exactly where you need it. I was afraid it’d expand in tube before exiting. I had it mixed and poured in funnel though within 20sec. Void and tube in vid both 5/8 in.

## Features

- Flotation Foam is a polyurethane 2-part foam that, when mixed in equal parts and poured in place this foam will soundproof, insulate, or provide extra buoyancy.
- 6LB. Density polyurethane flotation Foam 1 Quart Kit; Consists of 1 Pint of Part A and 1 Pint of Part B and produces 0.375 cubic feet.
- Once fully cured this foam can be laminated over with any type of polyester, epoxy or vinyl ester resin without melting.
- The 6LB density also works well in floating decoy or taxidermy applications as well as many other sculpting, casting, carving and other filling applications
- All expansion rates and times given are temperature critical. Temperatures below 75° F will lower the expansion rate therefore requiring more foam. Ideal working temperature is 75° to 80° F or above. Accurate measuring of these products is extremely critical. Working time before foaming: approx. 45 seconds Time before full expansion: approx. 5 minutes

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B0BLKLDH79 |
| Best Sellers Rank | #93,143 in Industrial & Scientific ( See Top 100 in Industrial & Scientific ) #125 in Urethane Adhesives |
| Brand | Fiberglass Supply Depot |
| Brand Name | Fiberglass Supply Depot |
| Color | Clear/Transparent |
| Compatible Material | Vinyl |
| Container Type | Can |
| Customer Reviews | 4.4 out of 5 stars 56 Reviews |
| Full Cure Time | 5 Minutes |
| Global Trade Identification Number | 00819794023276 |
| Included Components | 6lb poly foam |
| Item Form | Liquid |
| Item Package Quantity | 1 |
| Manufacturer | Fiberglass Supply Depot Inc. |
| Material | Foam , Resin |
| Material Type | Foam,Resin |
| Model | 00819794023276 |
| Other Special Features of the Product | Soundproofing, insulation, buoyancy, resin lamination compatibility |
| Part Number | Poly6lbgk |
| Special Feature | Soundproofing, insulation, buoyancy, resin lamination compatibility |
| Specific Uses For Product | Flooring, Repair, Casting, Wall Repair, Furniture, Woodworking, Wood |
| Unit Count | 32.0 Fluid Ounces |
| Viscosity Level | Low |
| Volume | 1 Quarts |
| Water Resistance Level | Not Water Resistant |

## Product Details

- **Brand:** Fiberglass Supply Depot
- **Item Form:** Liquid
- **Material:** Foam,Resin
- **Special Feature:** Soundproofing, insulation, buoyancy, resin lamination compatibility
- **Specific Uses For Product:** Flooring, Repair, Casting, Wall Repair, Furniture, Woodworking, Wood

## Images

![6LB Density Expanding Pour Foam, 2 Part Polyurethane Closed Cell Liquid Foam for Boats, Dock Flotation, Carving, Soundproofing, Filling Voids, and Insulation (Quart Kit) - Image 1](https://m.media-amazon.com/images/I/71D4G+ANFgL.jpg)
![6LB Density Expanding Pour Foam, 2 Part Polyurethane Closed Cell Liquid Foam for Boats, Dock Flotation, Carving, Soundproofing, Filling Voids, and Insulation (Quart Kit) - Image 2](https://m.media-amazon.com/images/I/61Xg7wuqwHL.jpg)
![6LB Density Expanding Pour Foam, 2 Part Polyurethane Closed Cell Liquid Foam for Boats, Dock Flotation, Carving, Soundproofing, Filling Voids, and Insulation (Quart Kit) - Image 3](https://m.media-amazon.com/images/I/81s3RjkkMiL.jpg)
![6LB Density Expanding Pour Foam, 2 Part Polyurethane Closed Cell Liquid Foam for Boats, Dock Flotation, Carving, Soundproofing, Filling Voids, and Insulation (Quart Kit) - Image 4](https://m.media-amazon.com/images/I/71Gbm9XW+IL.jpg)
![6LB Density Expanding Pour Foam, 2 Part Polyurethane Closed Cell Liquid Foam for Boats, Dock Flotation, Carving, Soundproofing, Filling Voids, and Insulation (Quart Kit) - Image 5](https://m.media-amazon.com/images/I/71fqAimxMaL.jpg)

## Questions & Answers

**Q: Can you press dents into this with your fingers once it’s fully cured?**
A: If you pour too much, too fast, you can create less dense regions that you can press your finger into. If you are patient with your pour it's pretty dang rigid - with that being said, if you put a tremendous weight through your thumb, you can still dent it a bit, but it's not easy to deform (I'm a 180 lbs male of average strength).

## Customer Reviews

### ⭐⭐⭐⭐⭐ Excellent Closed Cell Foam for Small Projects
*by H***E on December 23, 2025*

This worked well to fill a small void in a fiberglass boat step project I was working on. I am not sure how waterproof it would have been because I encapsulated it with epoxy before covering it with glass and Coosa board. One thing I had trouble with was figuring out how much to mix for the size of void. That information was provided but I way over estimated how much was needed. It was easy enough to cut off the excess with a hack saw. The image attached is "after" I made the adjustment to closer to the right amount. Making that calculation easier for smaller quantities would be nice. Along those lines, markers on the bottles for smaller batches would be very helpful. Nice product though.

### ⭐⭐⭐⭐⭐ Very good - just what I needed
*by B***8 on July 17, 2024*

This saved me having to rip out and re-mortar a tub. First time mortar bed for fiberglass acrylic tub and the mortar shrank leaving voids. This fills the voids perfectly, it’s incredibly solid now. In case you’re wondering as I was, this will go through a tube to get it exactly where you need it. I was afraid it’d expand in tube before exiting. I had it mixed and poured in funnel though within 20sec. Void and tube in vid both 5/8 in.

### ⭐⭐⭐⭐⭐ 6lb foam
*by T***Y on February 20, 2024*

As described. Easy to mix, drys quickly.

## Frequently Bought Together

- Fiberglass Supply Depot 6LB Density Expanding Pour Foam, 2 Part Polyurethane Closed Cell Liquid Foam for Boats, Dock Flotation, Carving, Soundproofing, Filling Voids, and Insulation (Quart Kit)
- 2 Lb Density Expanding Pour Foam, 2 Part Polyurethane Closed Cell Liquid Foam for Boat and Dock Flotation, Soundproofing, Filling Voids, and Insulation (Quart Kit)

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*Product available on Desertcart United Kingdom*
*Store origin: GB*
*Last updated: 2026-06-10*