Rainwater seal for roof tiles

[spiralqueen]

DH had a salesman round the other day trying to sell a treatment for roof tiles which prevented rainwater seeping into the tiles and then encouraging growth of lichens etc or stopping tiles from getting damaged by frost.

Seems like a scam to me but does anyone know anything about doing this?

£3,000 i was quoted but they were going to clean, coat and seal mine.
Haven't done it yet but it did seem quite a good idea, cheaper than a new roof.

This was featured on one of those 'House Horror'/Rogue Trader type programmes once.

It was viewed as unnecessary and a waste of money. They said there was no detrimental effect to having lichen on the roof tiles. Tiles keep water out. If your roof is leaking, get it repaired, that kind of thing.

Nearly always unnecessary and as deux says a classic scam like covering your house in a glue like never paint again paint and sealing in any moisture!All for a bargain price and they can start tomorrow.