Fabric convertible roofs require a little extra care over hardtop alternatives but it needn’t be arduous. An annual or bi-annual but thorough treatment will keep your top looking great and working well.
Renovo is a company that has been around for some time and is well known in Europe particularly among convertible classic car owners – those with the oldest and most worn tops. It wasn’t until recently however that their products have become available to the North American market too. If your fabric roof isn’t looking quite as good as it once did or is letting in water then this is a great way of renovating your roof as apposed to paying out a small fortune for a new one.
The Renovo range of products can be used individually but it isn’t until they are used in combination that they really begin to shine. We gave the Renovo range of products a good test on the oldest fabric roof we had available – an ageing BMW 3 Series Convertible. This particular roof is 16 years old and considering it has lived outside in the not-so-clement British weather for several years is a testament to the brand’s quality. That said, it was showing signs of age; a few scuffs here and there bit of fading particularly on the stitching which had become a pale grey. It still keeps out the rain but the fabric had lost its water repellence with any water immediately soaking into the surface layer. Worst of all, the roof had over the years picked up an ingrained level of dirt that couldn’t be cleaned away with any amount of scrubbing even with specialist hood cleaning products. This left it always looking a little brown and uneven.
Over a free’d up weekend I set about renovating this roof with the full ‘Fabric Kit’ that Renovo were kind enough to send me. This kit contains four products:
- Soft Top Canvas Cleaner – a water based cleaning product
- Soft Top Reviver – Renovo’s unique roof re-colouring product
- Ultra Proofer – a water repelling proofing liquid
- Plastic Window Polish – a fine liquid abrasive to remove hazing from plastic windows
Soft Top Canvas Cleaner
You will need some time to do a good job of this, a few basic materials and either fair weather or a garage with enough space to get around the car properly. I started with basic clean of the roof with a vacuum cleaner and a brush. Before getting to work on the roof it is worth going round all the seals and drainage channels and giving them a good clean – this is the area most likely to cause leaks. Once complete I moved on to the Soft Top Canvas Cleaner (the fabric version in this case although they also sell a vinyl roof cleaner). This is applied to a damp roof with a clean paint brush. Renovo recommend dampening the roof with a plant mister. Using a clean new paint brush makes a lot of sense; the last thing you want is a tint of the last colour you painted your bathroom all over your roof! The quality of the brush doesn’t really matter so I picked up a set of paint brushes from the bargain bin of the local DIY store. Renovo suggest once applied to leave this working away for 40-60 minutes to remove stubborn dirt but on this warm, dry day it had dried up completely in 20 minutes even in the shade. The next step was to start scrubbing with a sponge and warm water. A lather appeared immediately and it took quite a lot of scrubbing and rinsing before all the soap was washed away.
The result was an improvement but most of the ingrained brown marks remained – comparable to similar cleaning products I have used. I expect in cooler weather the cleaner would have been more effective and I considered having another go in the evening but I was too keen to try the next product in the kit – Soft Top Reviver.
Soft Top Reviver
With the roof now clean and dry it was time to apply the Soft Top Reviver which is also applied with a clean paintbrush. It obviously makes sense to wear rubber gloves when using this product to avoid staining your hands. The black (in this case, although other colours are available) liquid is thin in order to get into the weave of the fabric but this means that care must be taken to not get runs or drips. I was quite nervous that I might make a mistake and ruin the paintwork but thankfully any spills are easily removed with a wet cloth. I also found that the brush tended to spray small specks on the windows around the edges and I had to take care to clean this off too. The Reviver went on without problems and was left to dry over night.
The result was impressive with no streaks or patches just a roof that looked much like new. Of course, it can’t remove scuffs and tears but the re-coloured fabric looks great and the whole car looks rejuvenated. I must admit that the thought of using a permanent stain on a car roof is rather daunting but the process was straight forward and the result looks great.
The above image shows the roof before cleaning (on the left) and after one coat of Soft Top Reviver had dried (on the right).
Renovo advise two coats so another was applied the next day before re-proofing. My roof wasn’t in as poor condition as some I’ve seen and so the second coat made little difference to the appearance. I imagine the second application will help its longevity however.
The Ultra Proofer is a product I am more familiar with. Designed to improve water repellency and protect your convertible roof this is the best of all the alternatives I have tried. It not only renews the fabric’s water repellant barrier it also claims to inhibit the growth of mould or mildew and protect from UV rays. Although the roof should be water-tight without any surface treatment a good proofer will give added protection as well as preventing dirty water soaking into the fabric. Applying the product doesn’t take long if the roof has just dried from an application of the Reviver, otherwise it will need a thorough clean to prevent sealing in a layer of dirt. When applying, take care to wipe off any drips or dribbles on windows and paintwork. The product is clear but can leave a mark if it isn’t cleaned away. It will take a while to completely dry so keep the car away from water for a few hours. Once dry, any water that drips onto the roof bubbles up and pours off without soaking into the fabric much like freshly waxed paintwork.
Plastic Window Polish
Plastic windows are becoming rare on convertible cars but this E36 BMW has one as do many drop-tops from the 1990s and before. This particular car had the window replaced a few years ago as the old window had become so hazy that it effected visibility. Some time before the window was replaced I ordered some of Renovo’s Plastic Window Polish to attempt a renovation. Sadly although there was a marked improvement the plastic was too far gone with the hazing deep inside the material rather than just surface scratches. With the replacement window now a couple of years old I was keen to give this product a second try. The results were good. The small surface scratches that inevitably appear as the window is folded onto itself time after time could be removed and larger scratches could also be reduced. Great care must be taken to use a perfectly clean cloth because even the smallest piece of dirt can have a disastrous effect if rubbed into the window.
This comprehensive and effective range of products really impress when used in combination. Those looking to perform an intensive soft top roof renovation can look no further but don’t expect it to be two minutes work. The transformation of this roof was impressive but it took most of a weekend including cleaning and drying time. Fortunately the effect should last between 6 and 12 months for the Ultra Proofer and longer for the Reviver and remember, a couple of days work isn’t much compared with the cost of having a whole new roof fitted. I wouldn’t hesitate to recommend these products and will be using them again in future.
Renovo products are available worldwide from the UK producer or distributers including Convertible Top Renew in Canada.