Car Talk: Benefits of replacing old underlay and carpet

October 22, 2021 — by Richard Dawson

The obvious time to replace the carpeting in your car is when it’s stained, ripped, faded or oozes obnoxious smells. Less conspicuous are the pockets around the footwells and wheel arches starting to fray and becoming a rust trap. In any case, you’d want to remove the entire carpet, and to be sure that it sticks well and doesn’t become a magnet for dirt, spills and food, you’d also need to check the condition of the carpet underlay. This might have seen more damage due to heat, and any water making its way upwards. Replacement carpets and underlays are well worth the price and time, considering the protection they provide for the floor, and the convenience of soundproofing. 

You can find quality automotive carpet for sale from numerous retailers across Australia, in the colours and designs that best suit the interior. In addition, these are the same places that stock matching carpet underlay for the snuggest fit.  

Out with the Old and In with the New 

replacing the old carpet and underlay with new

Carpets and underlay serve several significant functions in vehicles. The most important is possibly reducing the overall heat generated from the engine and the exhaust. Protective layers in both carpets and underlays bring cabin temperatures to comfortable levels, so you won’t be needing to crank up the aircon. Next, is keeping the floor in the best possible condition. Liquids, food, mud and anything else can easily eat into the metal or wiring, which accumulated over time can cause rust, cracks and electrical failures. A new underlay will serve its intended purpose here well, and combined with a well-laid carpet on top even better. Heat and waterproofing are only part of the equation. New materials will reduce sound emanating from the engine, exhaust and transmission, so you can enjoy a conversation without having to yell, or have the stereo at full blast just to hear the lyrics. All this provides for a safer and more pleasurable ride.  

Interior rebuilds are regularly carried out on luxury vehicles or your everyday runabout. With new carpet and underlay you’re setting the foundations for bringing the look of the car back to as good as new. The carpet and floor are one of the most mistreated parts of the car, but so are the seats. Once you’re done with the carpet, the next step is tending to the seats. A wide variety of seat covers, in different materials, can liven up a drab interior and bring in more comfort.  

Carpet Underlay 

carpet underlay

If you’re restoring or rebuilding an older vehicle, this will have either a cotton shoddy or jute underlay. These fabrics deteriorate over time when exposed to increases in heat and moisture. Clumps are obvious signs that they need replacing. New underlay with a soundproof bottom and liquid and heat resistant top layer will keep things dry, quiet and cool. These are easily shaped to the contours of the floor and have an adhesive lining. They come in black, silver and grey if colours matter. You can continue with the carpet next or go for additional protection. Acoustic layers are good in cars with more spirit. They consist of several foam-based layers to deaden sound and repel water at the same time. Alternately, you can install a mass-loaded underlay made of vinyl, which luxury car makers use for sound insulation, so will be good in noisy diesels or big, lively petrols. This underlay is easily cut to shape, and can be removed at any time since it has a non-stick backing.  


car carpet

Once you’re done with the different types and layers of underlay it’s time to install the carpet. Areas that aren’t directly under the seats or footwells need stretch carpet. This includes places like the wheel arches, boot lining, along the roof, around speaker boxes and indoor panels. Stretch automotive carpet is made in a cut pile design, meaning it’s pliable and flexible to mould into differently shaped surfaces, and applied with a contact spray adhesive. In addition, it is durable and UV resistant, so won’t fade or discolour in the Aussie sun. In terms of sizing, there are stretch carpets in 1 by 2 metres, or for bigger vehicles, carpets in 2 by 3 metres. Buyers can choose from automotive carpet for sale in differing colours, from lighter tones, different shades of grey, or black. Mix and match these for interesting colour combinations with the rest of the interior.  

Cut pile moulded carpets with a smooth look are installed in newer cars, and this is what you and your passengers will be treading on. If these are ripped or damaged, replacement carpets are sold for all major brands and makes on the Aussie car market. Moulded carpets fit perfectly in your car, just make sure to order the carpet for your make and model. If you want to replicate an old-school look, say when restoring an old-timer, then go with a loop pile design. The textured surface here is a little more pronounced than cut pile carpets. Both carpets styles are produced from durable materials like nylon, polyester or polyurethane, meaning they’ll last for years. Surfaces are non-slip, and the driver’s side can include a rubberised insert. When picking the colour, you can go for new colours to accentuate different areas, say the seats or dash, or play it safe and stick to tried and test carpet tones.