Loft conversion: reuse or replace tiles?

[Itsatoughjob]

I've been quoted for a loft conversion, 30s semi, hip to gable conversion. The price includes reusing the existing concrete tiles (plain Marley types I believe). Any duff ones can be swapped out with those saved by introducing a dormer. Question is, should I insist on new tiles?
I like the idea that keeping the old tiles means that cost is kept down, also the roof will keep in the character of the neighbours. However am I asking for trouble in extending the life of 80yr old tiles? There seems to be lots of conflicting advice on the lifespan of a roof tile!

 

[^woody^]

If they are at life end, replace them. Tiles fail quite quickly after a period of gradual decline. And it can only take one severe winter to speed things up even more.

Btw, is not a case of you "insisting" on new tiles, like it's some sort of debate with your builder. You are the customer, you specify what you want, the builder does it.

 

[datarebal]

there are many makes of concrete plain tiles, they are not all the same by a long way.
marley type actually means very little.
find out the exact make and post back

 

[Itsatoughjob]

If they are at life end, replace them. Tiles fail quite quickly after a period of gradual decline. And it can only take one severe winter to speed things up even more.

Btw, is not a case of you "insisting" on new tiles, like it's some sort of debate with your builder. You are the customer, you specify what you want, the builder does it.

Sorry, yes, builder suggested I could reuse but of course I can spend more if I want to! So really it's me torn between the two and not wanting to make a bad decision

 

[Itsatoughjob]

there are many makes of concrete plain tiles, they are not all the same by a long way.
marley type actually means very little.
find out the exact make and post back

Hmm good question. I don't have any spares, to determine exactly what they are (i.e. a whole one to look at). I can say that they are plain concrete tiles, circa 1935 with an 'M' stamped on the back (which I interpreted to be 'Marley' but I might be totally wrong), held in place by 2 lug thingies. I can upload a pic of the internal, fwiw, can also ask the neighbour as I think he has some spares kicking around.