Pop-up rooflights have been fitted in caravans for a long time. Years ago they were often made from transparent orange plastic, which gave a really nice light inside the caravan; but for a number of years now they’ve been made from a white translucent plastic, and are usually double-skinned.

While the double skin is better for ventilation – it means that you won’t get a cold shower from dripping condensation first thing in the morning – the skins aren’t sealed, and the area between the layers can become very dirty. It’s not only unsightly, but it significantly alters the amount of light in the van, too.

My parents’ caravan is a classic example. It’s of an age before large Heki rooflights or sunroofs were fitted, and both pop-ups (one over the kitchen, the other in the washroom) were quite grubby. But one of the stays broke while they were on a recent trip away, which gave me the opportunity to replace one rooflight and clean the other one thoroughly. We sourced an identical rooflight from a caravan breaker on eBay for just a few pounds. (For John Wickersham’s expert advice on sourcing spare parts for caravans, please click here.)

How to fit a new pop-up rooflight

To replace such a unit, you’ll need the following tools:

  • A small flat-blade screwdriver or sharp knife
  • A crosshead screwdriver
  • A wide, flat blade (such as a chisel)
  • White spirit and a cloth
  • Mastic sealing strip (from a caravan dealer).

Tackling the work on your caravan

Working inside the caravan, prise out the four small screw caps (one at each corner, if fitted) from the inner trim, then remove the four screws that hold the trim in place. In our example (pictured right), this piece contained the blind and flyscreen, so if you’re planning to reuse them it’s worth giving them a quick clean.

With the inner trim removed, you’ll see the four metal clips that hold the unit in place. Release the clips by unscrewing each of the screws. These don’t need to be removed completely, but they do need to be loose enough so that you can turn them out of the way.

The next two stages are probably the hardest. You’ll need access to the exterior roof, and it can be a stretch if the rooflight is in the centre (as ours was)!

Once you’ve got there, you should break the mastic seal by working your way around the base of the rooflight assembly using a wide, flat blade. However, you must be careful not to damage the roof. Even after 16 years, the mastic on our van was surprisingly supple and grippy. Rather than over-stretching, I released one side then worked on the other from the opposite side.

Once the seal has been broken all the way around, the rooflight unit should simply lift out of the way. They’re quite light, so shouldn’t present any problems. If there is any resistance, make sure that all of the seal has been broken, or ask an assistant to check that the clips inside the van haven’t turned around.

Seal it safely

With the rooflight out of the way, remove all of the old mastic. I used a wide metal wallpaper scraper, but be very careful not to damage the roof. I was able to remove some of the mastic by hand, too. Once this has been done, thoroughly clean around the sides with white spirit, and ensure that none of the old mastic remains.

Once you’re happy that the roof is clean enough, cut four lengths of the new mastic sealing strip and place them along the edges of the rooflight aperture, overlapping the corners; make sure that there are no gaps underneath where the strips overlap by pressing one strip onto the other. Next, check that the new rooflight is clean where it sits on the roof (ie remove any old mastic and so on), then place it into the aperture, pressing the edges — and particularly the corners — into the mastic sealing strip. However, be careful not to press so hard that it cuts through the seal.

Once you’re happy that the unit is correctly seated, secure it from inside the caravan by using the four clips and screws. Back outside, carefully trim any excess sealing strip, making sure that you don’t pull any out from under the rim of the rooflight assembly.

Return inside the caravan and replace the trim, before securing it with the four screws. Check that, if the trim contains both the blind and flyscreen, they are at 90 degrees to the handles used to lift the rooflight; otherwise you’ll have difficulty accessing those handles.

Replace the four screw caps (if fitted), and the job is complete. You now have a new pop-up rooflight on your caravan.

How to dismantle and clean your rooflight

If the original rooflight is in perfect working order but simply needs a clean, it’s a very simple task to remove the covers so you can give it a good clean. It doesn’t matter whether the rooflight is open or closed for this.

Working outside the caravan, remove the four screws that secure the covers to the handles. Ensure that you retrieve both the screws and washers.

With these removed, the covers should simply lift off. Take care to get hold of both parts (particularly if there’s a breeze!) because they’re very light. Also, be sure to retrieve the four rubber washers between the lower side of the covers and handles – these are the main seal.

You’ll now be able to access all areas of both parts of the rooflight, so you can give them a clean with soapy water. (We have reviewed a selection of caravan cleaning products here.)

Despite the fact that these rooflights had never been cleaned before, the grime came off quite easily. A small brush helped us to access the gaps between the vent slots.

Once you’re happy that the parts are no longer dirty, you can reassemble them. Make sure the four black rubber washers are correctly seated before you replace the covers. After carefully putting the covers in place (so as not to disturb the rubber washers), replace the four screws and their washers. Nip up the screws, but don’t over-tighten them or you could damage the covers and threads.