I asked my storage place to look at resealing the arial on our caravan as it seems to have let some water in over winter. They told me not to bother with specialist sealants, and there were going to just seal round the edge (rather than remove it and fully reseal).
I've asked them to fully remove and reseal - but does anyone have any views on whether it does need a specialist sealant like Sikaflex?
Is it a hard job to do myself if so, as I'll save the cash on them not doing it properly and do it myself.
It would certainly make a far better job to remove/have the aerial removed so that the surface under the aerial and the aerial base can both be cleaned. This will effect a far better seal than just mastic around the joint. You could use Hodgsons Seamseal CV or W4 sealing strip (both non-setting) as alternatives.
When you apply sealant it is acting as a gasket which seals the component effectively so the component (in this instance the TV aerial) needs to be removed via the fixing screws, thoroughly remove any old sealant with white spirit (as previously mentioned) then wipe the surface dry with paper towel otherwise the new sealant won't stick. I had to replace my omni-directional TV roof aerial about 3 years ago and resealed with a product called 'Seamseal CV' so I have had the experience of doing the job in hand but I wouldn't dream of just sealing around the circumference of the base plate anyway as this is nothing more than a bodge up job. I believe in doing the job once and get it right first time.