Cleaning and waterproofing a convertible roof: step-by-step maintenance
Bird droppings, tree sap and stubborn discolouration don't disappear from a convertible roof on their own. You need a targeted approach: clean first, treat deep-set stains second, then waterproof. That order matters. Skip a step and the protective coating won't bond properly — and you'll find yourself dealing with the same problem all over again sooner than you'd like.
This guide explains exactly what to do at each stage and which product to use.
How do I know whether my convertible roof is still properly waterproofed?
Splash a small amount of water onto the roof. If it beads up and runs straight off, the water-repellent finish is still working. If the water soaks into the fabric or leaves a dark patch, the waterproofing has worn out.
A worn waterproofing makes the roof more susceptible to dirt and stubborn discolouration. Moisture that lingers in the fabric draws in more grime. The sooner you address it, the less work it takes.
Step 1: thoroughly clean the convertible roof
Always start with a thorough clean. Use Sprayhood & Tent Shampoo — a mild cleaner developed specifically for outdoor textiles, including fabric convertible roofs. Apply the product to the dampened roof, work it in with a soft brush and rinse thoroughly with water.
Discolouration caused by dirt and weather exposure sometimes sits deeper in the fabric structure than it appears at first glance. For stubborn soiling, allow the shampoo to dwell for a few minutes before you start brushing. Avoid working in direct sunlight and make sure the roof doesn't dry out too quickly during cleaning.
After cleaning, check whether all the dirt and discolouration has been removed. Still seeing deep-set contamination or stains? Move on to step two.
Step 2: treat deep-set stains directly
Bird droppings and tree sap are two of the most stubborn stains on a convertible roof. They can't always be removed with shampoo alone. If deep-set soiling or discolouration is still visible after cleaning, apply Fabric Power Cleaner directly to the affected area.
Apply Fabric Power Cleaner only to the stained spot — not over the entire roof. Allow the product to work in, brush gently and rinse thoroughly. Let the roof dry completely before moving on to protection.
Remove bird droppings as quickly as possible. The longer they dry out, the harder they are to shift — and the greater the risk of permanent discolouration.
Do I need to clean my convertible roof before waterproofing it?
Yes, always. A protective waterproofing only bonds properly to a clean, dry fabric. If you apply Sprayhood & Tent Protector to a roof that is still dirty or damp, you're effectively treating the dirt rather than the fabric — and water repellency will be noticeably reduced.
That's exactly why the order matters: clean, treat stains where needed, then protect. Not the other way around, and not at the same time.
Step 3: waterproof the convertible roof after cleaning
Once the roof is clean and dry, apply Sprayhood & Tent Protector. Spray the product evenly across the entire roof surface. Make sure you don't miss any areas, as uneven application leads to uneven water repellency.
Allow Sprayhood & Tent Protector to penetrate and dry as directed on the packaging. Ideally, work on a dry day out of direct sunlight so the product has time to bond properly.
Ultramar waterproofing products are PFAS-free, as are all other Ultramar maintenance products. A good protective layer helps limit new soiling and discolouration.
How often should I maintain my convertible roof?
That depends on how often you drive, where you park and what the weather is like. In most cases, one thorough treatment per year is sufficient. If the roof is outside year-round, twice a year may be worthwhile.
Use the water test as your guide: as soon as water stops beading off cleanly, it's time for maintenance.
FAQ: convertible roof maintenance
Can I use Sprayhood & Tent Shampoo on all fabric convertible roofs?
Sprayhood & Tent Shampoo is developed for outdoor textiles, including fabric convertible roofs made from polyester and acrylic. If your convertible roof is made from plastic or vinyl, use a product suited to that material instead.
Can I use Fabric Power Cleaner over the entire roof?
No. Fabric Power Cleaner is a targeted stain remover for deep-set soiling and discolouration. Apply it only to the areas where contamination is visible — not across the entire surface. Always clean the full roof first with Sprayhood & Tent Shampoo.
How long does Sprayhood & Tent Protector take to dry completely?
Refer to the instructions on the packaging. Allow the roof to dry fully before driving or folding it down. In cold or damp weather, drying may take longer.
What if discolouration is still visible after one treatment?
With heavily ingrained discolouration, a second treatment may be necessary. Repeat the cleaning process with Sprayhood & Tent Shampoo, then treat the specific area with Fabric Power Cleaner if needed. Allow everything to dry thoroughly before applying Sprayhood & Tent Protector.