Opinions on putting waterproof treatment on clay tiles?

[WJT]

I have asked this elsewhere but was hoping someone here may have experience or an opinion on using a hydrofuge (waterproof) treatment on clay roof tiles. We have a roof that was done 2 1/2 years ago with reclaimed tiles. Some of the tiles weren't very good quality and the roofer has just come out to replace them, paid by us of course. [:(] He is saying that there shouldn't be further problems but if I want insurance he will spray with a professional clear mat hydrofuge. By the way before anyone asks he didn't supply the tiles, he just fitted them.

He said he won't charge for labour but the cost is still €600 so not sure if it would really be a good idea or not. I can't seem to find much on the internet other that the thick coloured paint sealant coat stuff. Not much at all about clear water sealants.  Any advice would be most appreciated as usual. [:)]

[AnOther]

Surely roof tiles are, by definition, waterproof as standard so why would you want to apply any additional waterproofing product to them ?

Sounds like you are in danger of being conned out of €600

[Théière]

Normally yes Ernst, but as they age they become porous.

I have/still am looking at recycled plastic roof tiles, lots of companies and designs available and getting better each year. Should out last and out perform clay tiles.

http://www.wholebuild.co.uk/building-product/roofing-contractors/article/envirotilelight-weight-recycled-plastic-roof-tile-achieve-excellent-csh-ratings

[just john]

[quote user="WJT"]   reclaimed tiles. [/quote]

I have re-roofed my place and reused the old tiles on the outbuildings using a waterproof membrane underneath and then spraying the tiles with the brick water seal bought from B&Q for about £25 a can, covering 150sq m.  http://www.thompsonsweatherproofing.co.uk/products/product.jsp?id=1 which has been successful and preserves the look of the tiles, there is a specific roof treatment which though even more effective is not clear and so does not preserve the look of the tiles.

[WJT]

Hi John thank you. That certainly is a lot less expensive than the €600 he claims the one here costs! [blink]

I wonder why it doesn't say it can be used on roof tiles though. I will be going back to the UK soon and now think I would like to have this done before I leave and the winter weather so perhaps there is something similar in France. I hadn't received any response so was thinking about telling him to go ahead and do it but now I am not so sure about his generous offer. Thanks again.

[just john]

[quote user="WJT"] I wonder why it doesn't say it can be used on roof tiles though.  [/quote]

I guess it's down to guarantee claims, brick walls are vertical and thicker than tiles, sometimes old tiles are cracked which may not seal and in any case tiles get sheets of running water over the surface, who knows how long before a respray is necessary but so far so good; however the guck that gets a warranty looks too ugly to use. I reused them for the appearance with a membrane underneath and vertical battens.

[WJT]

That makes sense, thank you. I agree about the resin coloured types of products on the market. He assured me this wasn't it. He said it is clear mat and referred to it as hydrofuge. Just sounds ridiculously expensive compared to the Thompson product you showed.

I didn't think about it when I asked you but the Thompson product is probably similar to the French Sika product. In fact, I bought some from the local brico, 5 litres for about €35 and haven't used it yet for a solid gravelled area. I mentioned this to him and he said what he has is professional and is very expensive. So not sure if there really is a difference and if it is worth €600.

[AnOther]

[quote user="Théière"]Normally yes Ernst, but as they age they become porous[/quote]

If you are fitting new tiles then is that likely to become an issue either in your lifetime or the tenure of the property ?

[Théière]

[quote user="AnOther"][quote user="Théière"]Normally yes Ernst, but as they age they become porous[/quote]
If you are fitting new tiles then is that likely to become an issue either in your lifetime or the tenure of the property ?
[/quote]

No I don't believe it would be unless the property remains in the family though generations as a lot seem to have done in France.

One word of caution with the Thompson water seal, the Ultra version is a silicon formulation so any further coatings probably won't stick, ordinary version is good, likewise never applied it to roof tiles but I have one of my old French ones with me so could give it a try.