Peter is a licensed builder with over 45 years of experience in the construction industry. In 2012, his expertise in energy efficient construction inspired the invention of ThermaDoor Premium garage door insulation - the original purpose made garage door insulation in Australia.
More and more Aussie homeowners are rolling up their sleeves and insulating their garage doors themselves. Enter ThermaDoor’s Plain graphite garage door insulation kits. It’s a great weekend project that can help reduce heat and cold entering your garage through your garage door and improve overall comfort – especially if you’re using the garage as a workspace, home gym, kids play area or just trying to keep the temperature stable all year-round.
This guide explains what plain graphite polystyrene (GPS) is (and isn’t), when a budget plain polystyrene DIY garage door insulation kit makes sense, and when you’re better off stepping up to the ThermaDoor Premium Range DIY garage door insulation kit.
GPS (sometimes sold as “black” or “graphite infused” polystyrene) is a type of standard polystyrene with added graphite particles. The idea is that the graphite helps reflect radiant heat within the material, offering a slightly better insulation than white polystyrene of the same thickness and density. It’s not new. It’s been manufactured in Australia for over 15 years, and widely used in the construction industry as wall, ceiling and floor insulation. Currently it is sold by several large polystyrene manufacturers around Australia.
A simple Google search such as ‘graphite expanded polystyrene‘, or ‘graphite polystyrene insulation Australia‘ will provide you all the correct information on the product and its history.
That’s the honest truth: it’s a small performance bump, not a superpower.
Here’s the important bit: GPS is not thermally rated for garage doors. It doesn’t carry a calculated R-value under AS/NZS 4859.1&2:2018 for use in dynamic, metal panel garage door systems. If you’re building a new home – it’s not rated for energy efficiency assessments for garage doors under NCC 2022 or NatHERS 7-star targets.
It’s a plain polystyrene solution, designed for homeowners who want some improvement — not a premium grade garage door upgrade.
Our Plain range DIY Kits are ideal when:
And because it’s ThermaDoor, we still make sure it’s done right – with air gap spacers provided to avoid condensation, and access to installation videos to guide you through the process.
One of the biggest mistakes people make with any garage door insulation kits is gluing the insulation directly to the garage door skin.
That’s why all ThermaDoor kits — including our budget Plain range — include spacers to preserve the air gap, improving thermal resistance and extending the life of your garage door.
Garage doors are finely balanced. Add even a few kilos of insulation, and you may throw off that balance — putting extra strain on your motor and potentially risking injury. That’s why ThermaDoor always recommends having a garage door technician check and adjust your springs after installation. It’s not just smart — it’s in line with AS/NZS 4505 the garage door performance rule book
We keep it simple with two options:
Each ThermaDoor Budget Plain DIY Garage Door Insulation Kit Includes:
If you want high-performance, purpose-built garage door insulation, or you’re building a new home and planning to meet NCC 2022 and NatHERS 7-star requirements — ThermaDoor Premium is your go-to.
And yes — it’s also available as a DIY kit.
Australia’s original and purpose made garage door insulation, suitable for inclusion in energy ratings.
ThermaDoor is the only Australian garage door insulation brand that publishes dual-season, door assembly R-values, which is a requirement under AS/NZS 4859.2:2018. By declaring real world performance for the whole door (not just the material or values taken from wall or ceiling testing) and backing it with independent engineering and purpose-built design for sectional and tilt doors, we make it easy to choose with confidence – clear numbers, comfort all year round and no guesswork.
Read Best R-Value for Garage Door Insulation: Why Verified Ratings Matter to understand more about garage door insulation specific R-values and why we quote two of them.
| Feature | Budget Plain Polystyrene DIY Kit | ThermaDoor Premium Purpose Made DIY Kit |
|---|---|---|
| Thermally rated for garage doors | ❌ No | ✅ Yes |
| Supports NCC 2022 & NatHERS | ❌ No | ✅ Yes |
| Face finish | Plain graphite black or Plain white foam | Laminated white vinyl (easy-clean) |
| Backing | None | Laminated construction grade sisalation foil (heat barrier) |
| Air gap included | ✅ Yes (with spacers) | ✅ Yes (with spacers or pro install) |
| DIY-friendly | ✅ Yes | ✅ Yes |
| Best suited for | Basic thermal boost, low-impact use | New builds, energy upgrades, high performance |
At ThermaDoor, we stand by our values and believe homeowners deserve transparency – and insulation that works as promised.
If you want a simple, affordable upgrade, our Plain Graphite Garage Door Insulation Kit gives you a better-than-bare-metal solution without the marketing spin.
If you’re building a new home, renovating, or aiming for long-term thermal performance and tested compliance – ThermaDoor Premium is purpose-built, thermally rated for the garage door to the most up to date Australian Standards, and ready to help you meet energy efficiency targets with confidence, especially when margins are tight.
Either way, you can install it yourself. And either way, we’ve got your garage covered.
In Victoria and planning a DIY? Compare it with supply & install (spring adjustment included) and check determined R-values on our Victoria page.
Only marginally. True performance depends on thickness, density, air gap and installation methods in alignment with AS 3999 and AS/NZS 4505
No Australian Standard makes gluing non-compliant. However, gluing panels into the garage door does not allow for the important air gap that:
These are expectations under AS/NZS 4505 and best practice according to AS 3999
Unlikely. Energy assessors typically require bulk insulation R-values proven under AS/NZS4859.1&2:2018 on the specific application (garage doors). ThermaDoor Premium meets this, plain, untested graphite EPS does not.
If a supplier makes claims that it does, ask for the thermal engineer’s report specific to garage doors. If they can’t provide garage door specific documentation, treat the claim as unverified marketing spin.
Choose ThermaDoor Premium’s vinyl-laminated finish. Customers have painted this in the colours of their choice – win/win.
Whether you’re a hands-on homeowner chasing thermal comfort or just want a garage that looks as sharp as it feels – ThermaDoor’s DIY kits deliver honest performance less the marketing spin.
Call, text, or send an enquiry below to see if we have an installer in your area.
