Hi,

What is the best roofing material to go under a 4:12 concrete tile roof?

The house is 35 years old, tract home, standard red concrete S tiles. The paper is pretty well disintegrated. We are in Southern California, about 15 miles inland from the coast, so it’s very hot and dry for much of the year, with perhaps 13” of rain/yr, mainly in the winter months. The attic is vented. One room has a cathedral ceiling.

The estimates we are getting include:

Quote #1: Two layers of 40# Malarky SBS Tile Liner, attach with plastic cap fasteners; new 2” drip edge metal, new flashings, valley metal, roof to wall metal as per Tile Institute specs; 10 year warranty, labor only

Quote #2: Two layers of 40# UDL modified roofing membrane, install new primary roof flashings and secondary flashings to all pipes and vents, install new fortified plastic water barrier along ridge lines and where needed; 10 year warranty against leaks

Quote #3: Two layers of Malarky or equivalent UDL synthetic tile underlayment; double flash all penetrations; install factory formed hip, ridge and rake tile using approved weather block under trim pieces; install new metal roof edge; 15 year warranty

What is the best underlayment? Should anything else be under the felt to help insulate the house? Maybe just in the area with a cathedral ceiling?

The estimates we are getting all come to around $30k, including all new S profile concrete tile. Does this seem reasonable?

The house is one story, about 3,000 square feet, 4:12 pitch, standard height, three valleys, two chimneys, one sky light. There is lots of room and access all around. We’ve gotten four or five quotes, and they all come in around the same. It’s just odd that they’re so similar, although one had 10k less if we reuse the old tile and another was only 5k less if the old tiles are used.

I had heard some contractors take advantage of retirees, so we want to be cautious.

Thank you in advance for your suggestions and recommendation.

Jytte and Tess