Advice about ridge

Hi everyone,
I am new to this site, it looks like a really great site.
My partner and I are renovating a old cottage. We have taken off the tiles, replaced old wood, layed felt.
Question is why do people use mortar to hold down the ridge rather than screwing them in. Is it because of storms? Seal against moisture?
We have teracotta tiles that clip together.
Were we live we dont get strong winds, we do get severe frost. snow. heavy rain and sit in mist for weeks.
Any help or advise would be gratefully received.

The ridge was mortared in place because this leaves no exposed fasteners. When the fasteners (traditionally nails) are exposed to weather, they can corrode and can break the tile when they expand inside the hole (depending on the type of tile, and type of nail).

Tiles are refractory - there are some tile roofs that are over 1,000 years old. The weak link is the fasteners, which is why it’s imperitive they be protected from exposure. If installed right, tile could last indefinately.

yes you will have to find someone good with cement and
trowel it in along ridge.


Mortar prevents the weather from infiltrating into the exposed interior cavity.

Use a dye with the mortar to color co-ordinate it with the tile color.