DIY Guide

    DIY Underfloor Insulation Made Easy

    A warmer, drier home in just a weekend.

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    Installing underfloor insulation is one of the easiest ways to improve your home's comfort. Follow these simple steps to get it done right.

    The Process

    Six Simple Steps

    Adapted from the official EXPOL Installation Guide.

    STEP 01

    Measure Your Joists

    • Use the EXPOL DIY Ruler to size joist spacing
    • Measure in a few spots — sizes can vary
    • You may need a mix of panel sizes
    STEP 02

    Trim the Edge

    • If a panel is too wide, slice the concertina edge
    • Leave it ~5mm oversized for a firm friction fit
    STEP 03

    Slide Panels Between Joists

    • Push panel up firm against the floor — no air gap
    • Concertina cuts grip the joist for a tight fit
    • Keep 200mm clear of flues, downlights & exhaust fans
    STEP 04

    Secure the Panels

    • Existing floors: use EXPOL Z Clips, push-fit, no nails
    • New floors: fix Joist Saddles or galvanised nails diagonally
    • Position fixings ~200mm from each end
    STEP 05

    Work Around Wiring

    • Wrap any cables touching the panel with EXPOL Wireguard
    • Don't use a staple gun — take care around electrics
    STEP 06

    Notch Around Pipes

    • Cut neat notches with a sharp knife around plumbing
    • Leave 100mm clearance for future maintenance
    View full installation guide (PDF)

    It's Easier Than You Think

    No special tools

    A tape measure and a sharp knife is all you need.

    A weekend job

    Most homes can be completed in 1–2 days.

    Designed for DIY

    Friction-fit panels — no glue, no mess.

    Not sure how much you need?

    Use our underfloor calculator to get the right product and quantity for your home.

    Calculate Now

    Ready to get started?

    View the full underfloor range or find your nearest stockist.

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