Residential roofing · Tile
Tile roof underlayment replacement
Clay tile can last 50 to 75 years. Concrete tile runs 40 to 50. The felt underneath it - the part that actually keeps water out of your house - is done at around 20 to 25. That gap is why a tile roof can look flawless from the street and still be soaking the plywood.
- CA Licence #1052777
- We price match like-for-like bids
- 5–10 years on labor and workmanship
Why a relay, when the tile is sound
What a lift-and-relay actually buys you
Keep the tile you already own
Original clay or concrete tile goes back on, not a full new covering - the biggest cost driver in a reroof is avoided.
A fresh 20-25 year clock underneath
New underlayment restarts the layer that actually keeps water out, without touching the durable layer that does not need replacing.
Every flashing replaced, not reused
Valley metal, counterflashing, and pipe jacks are the details cut-rate relays skip. We replace all of it as standard scope.
A written comparison, not a guess
We lift tile and show you the felt before recommending relay over replacement, so the decision is based on what is under your roof.
The tile is not what keeps water out
This is the part almost nobody explains, and it is the whole reason this page exists. A tile roof is a two-part system:
- The tile is the wear layer. It sheds most of the water, takes the sun, takes the hail and the falling branches, and protects everything under it from UV. It is not sealed and it is not waterproof.
- The underlayment is the waterproofing plane. It is a membrane laid over the roof deck before a single tile went on, and it is the layer that decides whether water reaches your ceiling.
Water gets under tile on every serious storm. Wind drives it up under the laps and sideways through the head joints. It wicks up the underside of a tile by capillary action. On a windy night it comes in from three directions at once. None of that is a defect - the system is designed for it. The water lands on the underlayment, runs down the membrane, and exits at the eave.
For the first twenty years or so it does exactly that. Then the felt gets brittle, cracks open at the fastener penetrations and the laps, and the same water that has always been getting under the tile starts going into the deck instead of down it.
Why the roof looks perfect while it is failing
Two materials with completely different lifespans are stacked on top of each other, and only the durable one is visible.
The tile is shading the underlayment from direct sun, which helps - but the air space under tile is brutally hot in a Southern California summer, and heat is what kills asphalt felt. Every day the membrane heats, expands, and cools. The volatile oils cook out of the asphalt. What is left goes hard and stops moving with the deck, and once it cannot move, it splits.
That is why failure is not uniform. On almost every house we open up, the south and west slopes are shot while the north slope still has some life left. It is why a leak can show up in one room this winter and a different room next winter - you are not chasing one hole, you are watching a membrane run out.
The age math for San Gabriel Valley housing stock
A lot of the tile in Pasadena, Alhambra, San Marino, South Pasadena and Monterey Park sits on pre-1940 Spanish Colonial and mid-century homes. The original clay tile on a 1928 house may be 98 years old and completely serviceable. What matters is not the age of the tile - it isthe date of the last underlayment.
- Under 15 years since the last relay or reroof - monitor, no action needed.
- 15 to 25 years - worth lifting tiles and looking, especially if you have had any leak at all.
- 25 years or more - assume the felt is at or past end of life and plan around it, leak or no leak.
- Nobody knows - this is the common case on an older home. That is what an inspection is for.
If your house was reroofed in the 1980s and the tile was saved and relaid, the tile is fine and the underlayment is roughly 40 years old. Both things are true at the same time.
How to tell your underlayment has failed
What you see from inside the house
- Ceiling or wall stains that appear after wind-driven rain but not after a steady, calm rain.
- Stains that show up in a different spot each storm season.
- Rusty nail tips, dark streaking on the underside of the sheathing, or daylight through the deck when you look in the attic with the lights off.
- A musty smell in the attic or in a closet against an exterior wall.
- Peeling paint or a soft spot at the top of an interior wall, with no plumbing above it.
What you see on the roof and around the house
- Black granules and asphalt grit washing out of the downspouts. That is the felt eroding and leaving through the gutters.
- Felt visible and shredded at the eave line, where the underlayment turns out over the fascia.
- Tiles that have slipped or shifted, especially in rows - the fasteners have lost their grip in a soft deck.
- Mortar cracked out of the ridge and hip, or ridge tiles that rock when touched.
- Efflorescence or heavy moss on the lowest courses, where the roof stays wet longest.
- Sagging or wavy plane in the roof surface, which usually means the deck under it is going.
The pattern that gives it away
Individual symptoms are ambiguous. The pattern is not. If all of these are true, you are almost certainly looking at underlayment failure rather than a repairable leak:
- The leak appears with no broken or displaced tile anywhere near it.
- It only shows in driving rain, not in light rain.
- Someone already did a spot repair, it held for a season, and then a new leak opened up nearby.
- The roof is 20-plus years past its last underlayment.
The one thing that actually settles it
Lift the tile and look. There is no substitute, and anyone quoting a relay without doing it is guessing. We pull tiles in several places - a sun-beaten south or west slope, a valley, next to a plumbing penetration or chimney, and one representative field area - and we look at what the felt does in our hands. Felt at end of life tears like a saltine instead of bending. That is the test. We show you the photos of what came out.
If the membrane is still pliable and the fastener holes are still tight, we will tell you that, and we will tell you to fix the leak you actually have instead of buying a relay you do not need yet.
What a lift-and-relay actually involves
"Lift-and-relay" - also called a tile lift and reset, or underlayment replacement - means the tile comes off, everything under it is rebuilt, and the same tile goes back on. Here is the real scope, in order.
- Identify and document the tile. Profile, manufacturer where it is still stamped, and color blend. We confirm a source for matching replacements before we start, not after we discover a pallet's worth of breakage.
- Stage the removal. Tile comes off in sections and gets stacked in courses so it goes back in its original pattern. We only open what we can dry in the same day. Field tile usually stacks on the roof; on a steep or a two-story roof it has to be lowered, which is real labor and it shows up in the price.
- Strip the old underlayment and pull the old fasteners.All of it, down to bare deck. Leftover nails telegraph through new membrane and become the next leak.
- Inspect and repair the deck. Soft, delaminated, or rotted sheathing gets replaced. On pre-1940 homes we frequently findspaced or skip sheathing - 1x boards with gaps, put down for wood shake before tile was ever on the house. That has to be sheeted over with solid decking to carry modern underlayment properly, and it is the single most common reason a relay quote comes in higher than the homeowner expected. We would rather tell you that up front.
- Install new underlayment. Spec depends on slope, exposure, and budget - see the comparison below. Where the roof pitch falls between 2½:12 and 4:12, code calls for a double underlayment application under clay and concrete tile.
- Replace every flashing. New valley metal, headwall and sidewall flashing, pipe jacks, chimney counterflashing, skylight curb flashing. This is not optional and it is where cut-rate relay bids save money: reusing 40-year-old galvanized valley metal under brand new underlayment means the assembly fails at the valley while the paperwork says the roof is new.
- Set battens or elevated battens if the system uses them.Where battens are used, they need to drain - a flat batten laid straight across the slope dams water on the membrane it is supposed to protect.
- Relay the tile. Original tile back in the original pattern, breakage swapped for matching stock, fastened to current requirements, and the ridge and hip reset. Mortar-set ridge rarely survives removal; a modern dry-ridge system is often the better rebuild and we will walk you through the tradeoff for your house.
- Clean up and inspect. Debris hauled, magnet sweep of the drive and yard, gutters cleared of the grit that comes off the old felt, and a walkthrough with photos of what was under there.
Underlayment options, honestly compared
This is the decision that determines how long the relay lasts. Paying for the labor of lifting an entire tile roof and then putting the cheapest possible membrane back under it is poor value, and it is a common bid.
| Underlayment | What it is | Where it makes sense |
|---|---|---|
| Asphalt felt ASTM D226 Type II ("30 lb") | The traditional saturated organic felt. The material that is failing on your roof right now. | Code-legal and the cheapest option. If you are relaying a tile roof you intend to keep for decades, you are buying the same 20-year clock over again. |
| Synthetic underlayment | Woven polypropylene or polyester sheet. Does not absorb water, does not dry out and go brittle the way felt does, much stronger tear resistance around fasteners. | A solid mid-tier choice for most of the roof. Confirm the specific product is approved for tile and rated for the temperatures under tile in this climate - not all synthetics are. |
| Self-adhered SBS-modified "peel and stick" | Rubberized asphalt membrane that bonds to the deck and self-seals around fasteners. High-temperature grades are made specifically for tile. | The premium option, and the one worth the money in valleys, at eaves, around chimneys and skylights, and on low-slope sections - at minimum. Whole-roof application is what we would specify on a house you plan to keep. |
Manufacturer service-life claims vary widely and depend heavily on the specific product and on installation. We will put the actual product name and specification in your written estimate so you can look it up yourself and compare bids on equal terms.
When full tile replacement makes more sense than a relay
A relay is not automatically the right answer. It is the right answer when the tile is sound and the membrane is not. Here is when we will tell you to replace the tile instead.
The tile itself is worn out
Concrete tile does have an end of life. Look for spalling and flaking surfaces, crazing, tiles that are chalky and shed material when handled, edges crumbling, or a high percentage already cracked. Concrete tile also absorbs more water as it ages, which makes it heavier and more brittle - exactly the wrong combination for a job that involves handling every single piece twice. Clay tile is much more durable and usually survives; a badly weathered concrete tile roof at 45 or 50 years often does not.
Your profile is discontinued and there is no salvage
Breakage is normal. Breakage you cannot replace is a problem. If the tile is an obsolete profile with no salvage yard source, expected breakage turns into patches of visibly mismatched tile across the field. Sometimes the fix is to harvest tile from a rear or garage slope for the street elevation and put new, close-match tile where nobody sees it. Sometimes it means replacing.
The deck has to come off anyway
If widespread rot or full skip-sheathing replacement means we are rebuilding the deck across the whole roof, the labor of carefully salvaging tile becomes a bigger fraction of a job you are already deep into. At that point the arithmetic sometimes favors a new roof - lighter material, a fresh system, and a full manufacturer warranty on the covering rather than reused tile.
You want a different roof, or a lighter one
Standard-weight concrete tile is heavy. If you are converting to a lightweight tile or to architectural shingle for structural or budget reasons, that is a replacement, not a relay. Be aware that changing roofing material on a street-visible elevation can trigger design review in Pasadena's landmark districts and in other cities with preservation ordinances - like-for-like generally does not, a material change generally does. Confirm with your city's planning department before you commit.
Solar is going on the roof
If a solar array is in your plans, sequence matters enormously. Do the underlayment first. Removing and resetting an existing array to relay the tile underneath it is a real line item, and doing it in the wrong order is a genuinely expensive mistake.
How we decide: we lift tiles in several locations, check the deck, count usable tile, and price both paths where both are reasonable. You get the comparison in writing. If a relay is the better value on your house, we will say so even though a replacement is the bigger job.
What drives the cost
We do not publish square-foot pricing, because on tile work it would be close to meaningless - two 2,400 square foot houses on the same street can differ by a large multiple depending on what is under the tile. These are the variables that actually move the number, roughly in order of impact.
Deck condition
The biggest swing, and the one nobody can fully price from the ground. Isolated rot at valleys and eaves is normal. Full skip-sheathing overlay across an entire pre-1940 roof is a different project.
Roof complexity
Valleys, hips, dormers, multiple planes, chimneys, skylights, and every penetration. A simple gable relays fast. A cut-up roof with six valleys does not.
Pitch, height, and access
Steep slopes need staging and fall protection. Two-story tile has to be lowered rather than stacked. A narrow lot with no place to set a dumpster costs more than a wide one.
Tile type and availability
Salvageability, expected breakage, and whether matching replacement stock exists. Heavy standard-weight concrete costs more to handle than lightweight tile.
Underlayment specification
Felt versus synthetic versus full self-adhered is a real material and labor difference - and the single biggest lever on how long the result lasts.
Flashing and metal scope
New valley metal, chimney counterflashing, skylight curbs, and any sheet metal fabrication. Masonry chimneys in older homes often need more than a standard flashing kit.
Ridge and hip system
Rebuilding a mortar-set ridge versus converting to a dry-ridge system, and how much ridge and hip length the roof actually has.
Solar, permits, and disposal
Array removal and reset if applicable, city permit and inspection fees, and disposal - old felt and broken concrete tile are heavy.
If you already have a bid, bring it to us. On a like-for-like scope from another licensed contractor, we will match it. "Like-for-like" matters more on tile than on almost any other roof: compare the underlayment product by name, whether all flashings are being replaced, and whether deck repair is a real allowance or an open-ended extra.
Code and permit items worth knowing
Requirements differ by city and change over time. These are the ones that come up most often on tile work in our service area. We verify the specifics for your address and jurisdiction before we write the estimate.
You cannot roof over tile, and California limits layers to two
The California Residential Code caps a structure at two roof coverings at a time, and a house already carrying two layers has to be stripped before new roofing goes on. On tile the question is academic: nothing gets installed over a clay or concrete tile profile. A tile roof always comes off - the only decision is whether the same tile goes back on.
Double underlayment on lower slopes
For clay and concrete tile on roof slopes from 2½:12 up to 4:12, the code requires a double underlayment application. Plenty of 1920s and 1930s Spanish Colonial roofs in the San Gabriel Valley have sections in exactly that range. If a bid on a low-slope tile section shows a single layer, ask about it.
Title 24 2025 cool roof requirements
The 2025 California Energy Code applies to building permits applied for on or after January 1, 2026. For existing low-rise residential roof alterations, the prescriptive steep-slope requirement is an aged solar reflectance of 0.20 and thermal emittance of 0.75, or an SRI of 16, and it is triggered when more than 50% of the roof or more than 1,000 square feet - whichever is less - is replaced or recovered.
Two things worth understanding before you assume this dictates your tile color:
- Climate zone matters. That prescriptive steep-slope requirement applies in climate zones 10 through 15. The San Gabriel Valley core sits in zone 9; Bakersfield and the southern San Joaquin Valley are inside the 10-15 band. Your address determines it, and the plan checker confirms it.
- The code lists equivalent alternatives. The energy code treats certain assemblies as equivalent to a cool roof - among them a ceiling insulated to R-38 or better, or a compliant attic radiant barrier. Roof area covered by building-integrated solar is also excluded. Compliance is often achievable without changing the look of the roof.
Compliance is documented with Cool Roof Rating Council product labeling, so whatever is specified has to be a CRRC-rated product.
City of Los Angeles cool roof ordinance and the LADWP rebate
If the property is inside the City of Los Angeles, the city's cool roof requirements apply to residential reroofing citywide - a0.20 three-year aged solar reflectance and 0.75 thermal emittance for steep-slope roofs, with 0.63 / 0.75 for low-slope. Exemptions include roof repair and replacements covering 50% or less of the total roof area.
LADWP customers should also look at the Consumer Rebate Program, which has paid a base rebate of roughly $0.20 per square foot for qualifying CRRC-rated cool roof products installed over conditioned space, with a higher tier for higher-performing products. Patios, carports, and overhangs do not count, and applications are time-limited after purchase.Confirm current rebate amounts and terms directly with LADWP before counting on them - utility program terms change, and we will not promise you a rebate we do not administer.
Because a lift-and-relay reuses the existing tile rather than installing a new roof covering, how these requirements apply to a relay is a question for plan check on your specific job. We raise it with the building department up front instead of discovering it at inspection.
Sources: California Energy Commission 2025 Energy Code (Title 24, Part 6), Cool Roof Rating Council, City of Los Angeles Green Building Code, LADWP Consumer Rebate Program, California Residential Code Chapter 9. Verified August 2026 - confirm current requirements with your building department.
Tile underlayment questions we get asked
My tile roof leaks but no tiles are broken. How is that possible?
The tile is not the waterproofing layer. Tile sheds the bulk of the water and takes the UV and impact, but wind-driven rain gets under it on every storm by design. What actually keeps water out of your house is the underlayment on the deck beneath the tile. When that membrane goes brittle and splits, you get leaks with no visible damage above them.
How long does tile roof underlayment last in Southern California?
Organic felt underlayment is generally expected to last around 20 to 25 years, and SoCal conditions push it toward the short end. The tile shades the membrane from direct sun, but the air under tile gets very hot, and daily heat cycling drives the asphalt out of the felt until it cracks. South- and west-facing slopes usually fail years before north slopes on the same house.
What is a tile lift-and-relay?
We remove and stack your existing tile, strip the old underlayment, repair the deck, install new underlayment and new flashings, then reinstall the same tile. You keep the roof you have and get a new waterproofing system under it. Tiles that break during removal get replaced with matching salvage or new stock.
Can you just put new underlayment over the old one?
No. The old felt has to come off. New underlayment installed over failed felt still relies on the failed layer for a flat, sound substrate, and it buries deck rot you have not looked at. There is also no way to replace valley metal or headwall flashing without stripping to the deck, and old flashing is where a large share of tile-roof leaks actually start.
Can I add a layer over a tile roof instead of tearing it off?
Not practically. California limits a structure to two roof coverings at a time, and nothing gets laid over clay or concrete tile in any case - the profile is not a surface you can roof over. A tile roof always comes off, either to be relaid or to be replaced.
How much tile breaks during a lift-and-relay?
Some breakage is unavoidable - older concrete tile is more brittle than it looks, and mortar-set ridge and hip tile rarely survive removal intact. The real question is whether your profile is still available. Before we quote a relay we identify the tile and confirm we can source matching replacements. If the profile is discontinued and there is no salvage source, that changes the recommendation.
Does a lift-and-relay need a permit?
Reroofing work is permitted work in essentially every jurisdiction we serve, and a relay is reroofing. Requirements and fees vary by city, and unincorporated Los Angeles County is its own process. We pull the permit and handle inspection scheduling as part of the job.
How long does the roof stay open?
We work in sections and dry the roof in before we leave each day, so the house is never left with an exposed deck overnight. Most single-family relays run several working days depending on size, pitch, complexity, and how much deck has to be replaced.
Why call Green Coast for tile work
- We will tell you if you do not need it. If the felt is still pliable, the honest answer is a repair, and that is what we will quote.
- Named specifications in writing. The actual underlayment product, the flashing scope, and the deck repair allowance appear in your estimate. That is what makes bids comparable.
- Two CSLB classifications, not one. We hold both C-39 (Roofing) and B (General Building), where most roofing competitors carry only the C-39. That matters on tile work specifically, because a relay frequently uncovers deck carpentry - skip sheathing, rotted rafter tails - that a C-39-only contractor has to subcontract out.
- We price match like-for-like bids from another licensed contractor.
- 5–10 years on labor and workmanship, on top of the manufacturer warranty on materials.
- California license #1052777 - licensed, bonded, and insured, in business since 2019. Verify it yourself at cslb.ca.gov.
What you end up with
The tile you already had, back in its original pattern, over new underlayment, new flashings, and a documented deck repair - with a written scope naming the actual underlayment product so you can verify it went on the roof. If a relay is not the right call for your house, you get that answer instead, in writing, before any tile comes off.
Where we do this work
Tile relay is concentrated in the older housing stock of theSan Gabriel Valley and Los Angeles County, and it comes up on tile and manufactured-home roofing inKern County as well. See our full service area for the cities we cover.
Related services
- Roof repair and leak diagnosis - if the membrane still has life in it
- Reroofing and roof replacement - when the tile itself is finished
- Roof inspections and certifications - written report, useful for a sale
- Roof maintenance - what to do between now and the relay
- All residential roofing services
Find out what is under your tile
We will lift tiles in several places, show you what the underlayment is actually doing, and give you a straight recommendation - repair, relay, or replace.
Serving the greater Los Angeles area, the San Gabriel Valley, and Kern County. CA License #1052777.