My roofing tiles are Redland plain concrete 10.1/2" x 6.1/2".
I have found a broken tile that has snapped horizontally in half.
Unfortunately, the tile is adjacent to valley tiles, twice nailed and only
two rows down from the cement bedded ridge tiles. Consequently there's no
chance of removing its top half and fitting a new tile unless I first remove
the ridge tiles, which I don't want to do.
My best option is to cement/glue the broken bottom half of the tile back in
My question is; what is the best adhesive to use that is waterproof and will
withstand slight movement and thermal cycling?
Cement mortar always seems to crack off over time.
A Google search suggested using RT-600, but I can't track it down in the UK.
Any recommendations anyone?
What about glueing something on the bottom of the tile,
across the break, to keep the pieces together and prevent
water going through? Some sort of material that won't rot.
If the glue can go through it, put a piece of polythene
underneath so you don't inadvertently stick it to the tile
There are grab adhesives which will strongly bond masonary
products, even when wet. I used to use Wickes Master
"Forget Nails" Waterproof which was excellent, but they
stopped doing that range. Someone can probably suggest a
current product which works well.
[email address is not usable -- followup in the newsgroup]
Yes, I did consider that. I thought of using either slate, or a piece of
the thin cement fibre-board that used to be commonly used for soffits,
although the cement fibre-board probably contained asbestos has since been
There doesn't seem to be a lot of choice. The material wouldn't want to be
any more than 3 - 4mm thick. Maybe fibreglass sheet?
I did considered using a piece of fine stainless steel mesh with polythene
behind. The adhesive would pass through the mesh and bond well.
This still leaves the question of which adhesive to use. I wondered about
an external tile adhesive such as would be used for tiling a swimming pool.
I've just read the spec sheet for RT-600:
DANGER! EXTREMELY FLAMMABLE. HARMFUL OR FATAL IF SWALLOWED. Contains Naphtha
Solvents, Toluene and Ethanol. Keep from heat, sparks and flame. Vapors may
ignite explosively. Extinguish all flames, burners, stoves, heaters and
pilot lights and disconnect all electrical motors and appliances before use
and until all vapors are gone. Prevent build up of vapors by opening all
windows and doors to achieve cross-ventilation. May cause central nervous
system effects including dizziness, headache or nausea. Contains n-Hexane
which can cause peripheral polyneuropathy and central nerve damage. KEEP OUT
OF REACH OF CHILDREN.
That more than enough to give our killjoy H&S Executive a fit of the
vapours. I doubt I'll find it for sale in the UK!
OK, I can answer my own question now. The best adhesive seems to be
Araldite epoxy resin (original, slow-set Araldite, not the quick-set
I deliberately snapped a spare roof tile in half and then glued it back
together with Araldite. I left it for a week, and then tried to break it.
The glued joint held firm. I then dropped the tile onto a concrete surface,
whereupon it predictably shattered into many pieces. However, nowhere did
it break along the glue line.
I have now glued my broken roof tile back in place, and the result seems
It's important that the tile is a simple break with matching edges to glue.
Choose a hot, dry, sunny day - the Araldite needs 5-hours to set! Wire
brush the broken edges to remove any loose material. Coat both edges with
Araldite and push the two tile pieces together. I used a piece of plastic
under the tile to prevent the adhesive from sticking to the tile beneath. I
held the broken piece of tile in position with wire hooks and elastic bands,
until the Araldite had set.
Providing the integrity of the glued joint isn't compromised by months of
rain and thermal cycling, the job's a good un.
Milliput ( http://www.milliput.com/prod.htm ) is a coloured epoxy putty
that resembles earthenware ceramic and does a similar job.
I've repaired the odd terracotta pot with that with similar results to
those which you describe.
(in-ep-toc’-ra-cy) – a system of government where the least capable to
HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.