elderly concrete roof tile question

[AHI in AR]

I did an inspection on an 82-year-old home today with concrete roof tiles. Originally, they had some sort of green colored coating on them. However, in some areas the coating had worn off exposing the aggregate. My concern is that they are now more porous and freeze thaw damage or acid rain damage may be a greater issue. This sort of roofing material is extremely rare around here. Most homes this age with tile roofs have a clay tile. What would you guys who have experience with this material say about this?

[Garet]

I would take a good, hard look all over the roof. If it's near the end of its useful life then it will show. I've seen several older concrete tile roofs where a few random tiles are beginning to break down. If it's just a few they can be replaced with replicas and/or salvaged tiles available from specialty suppliers. If a lot of tiles are breaking down then it's time to write a much bigger check.

[Marc]

I haven't any experience with this type of roofing finish. Given your description, I might also be suspicious. If research yielded nothing then I would look for evidence of the consequences of those suspicions, and write it up accordingly. If no evidence, I would still disclose the finding and my concerns about it. I would also augment the write up with comments during the verbal report to get a feel from the client and not blow the issue up out of proportion.

Hopefully, some one else has more to offer than I on this.

Marc

[Ben H]

Pics?

[Jim Katen]

I did an inspection on an 82-year-old home today with concrete roof tiles. Originally, they had some sort of green colored coating on them. However, in some areas the coating had worn off exposing the aggregate. My concern is that they are now more porous and freeze thaw damage or acid rain damage may be a greater issue. This sort of roofing material is extremely rare around here. Most homes this age with tile roofs have a clay tile. What would you guys who have experience with this material say about this?

I can only describe how they work in my area. Your area might be different. The coating is a colored slurry that's applied to the top of the tiles. Around here, that coating begins to wear off at around the 10-15 year mark and it's usually mosty gone by the 20-25 year mark. You'll start to see it erode at the high points of the tiles' profiles first. Most manufacturers (all of the ones that I'm aware of, actually) specifically exclude wear to this coating from their warranties. They insist that the strength and prformace of the tiles is unaffected by the color loss. There are contractors who will apply coatings to the tiles to match the old color or to give them a new color. These coatings typically carry an 8 or 10 year warranty.

I don't believe that the tiles you saw are 80+ years old. Around here, they usually last 40 or 50 years. The oldest one I ever saw was 60 years old and it was leaking like a sieve. The tiles actually had holes in them that I could stick my fingers through. You couldn't press on them with your hand without breaking them, let along walk on them.

Also, in my area, people often have to replace their old concrete tile roofs way before the tiles are worn out because the felt has failed. It's possible to remove the tiles, replace the felt and reinstall the tiles a couple of squares at a time and some folks do that.

-Jim Katen, Oregon

[john_opwin]

As far as i am concerned the buildings made by concrete and steel angles does not have more long life than 60 years. The main cause behind it is acid rain. That's why steel's angles should be polished with such chemical which resists corrosion. The life will be increased by itself own.

[Jim Katen]

As far as i am concerned the buildings made by concrete and steel angles does not have more long life than 60 years. The main cause behind it is acid rain. That's why steel's angles should be polished with such chemical which resists corrosion. The life will be increased by itself own.

Hi John,

I appreciate your particularly lucid and informative posts, but I'm confused. Your profile says that you're from Bridgeport, Connecticut, yet when I go to your web site (which requires a Korean language pack to view properly) I see that you're from Atlanta, Georgia. On that web site, there are two inspectors, neither of whom is named John Opwin.

Is your profile in error?

- Jim Katen, Oregon

[AHI in AR]

As far as i am concerned the buildings made by concrete and steel angles does not have more long life than 60 years. The main cause behind it is acid rain. That's why steel's angles should be polished with such chemical which resists corrosion. The life will be increased by itself own.

Hi John,

I appreciate your particularly lucid and informative posts, but I'm confused. Your profile says that you're from Bridgeport, Connecticut, yet when I go to your web site (which requires a Korean language pack to view properly) I see that you're from Atlanta, Georgia. On that web site, there are two inspectors, neither of whom is named John Opwin.

Is your profile in error?

- Jim Katen, Oregon

"particularly lucid and informative posts"

Now THAT'S funny.

BTW, Jim...thanks for your much earlier reply to my original question. It was not only lucid but helpful to boot.

[thomop]

Hi there AHI in AR.

My name is Phil Thomson from Guardian Roofing in Australia.

I am with one of the other posters. I don't really think they could have been concrete roof tiles.

I have an article you can look talking about the history of concrete roof tiles in Australia. I haven't done any research for roof materials in USA, but one can assume they would have been manufactured at around the same time. Site is: www.guardianroofing.com.au/history.html

Cheers,

[Jim Katen]

Hi there AHI in AR.

My name is Phil Thomson from Guardian Roofing in Australia.

I am with one of the other posters. I don't really think they could have been concrete roof tiles.

Why?

- Jim Katen, Oregon

[hausdok]

They've got a lot of tile roofs down under; that's for sure. Every once in a while I peruse the Aussie real estate listings. It's amazing how so many of their homes look like the typical home one would find in Pheonix or Las Vegas.

When he described it in the initial post, I tought some kind of clay tile roof with the glazing breaking down.

Don't give my ramblings much credit, Kevin, I see tile roofs - concrete or clay - about once every 1500 homes. I'm definitely no expert.

ONE TEAM - ONE FIGHT!!!

Mike

[AHI in AR]

As I said to start off, these types of roofs are pretty rare here also. However, I have seen clay tiles and this was not clay. I have no photos because the worn areas were generally ridges only clearly visible from 2nd floor windows. The windows were painted shut so I couldn't open them for a shot, and the glass was too dirty to shoot through. But I could clearly see concrete-colored small aggregate where the green coating was gone.

[thomop]

Hi Kevin,

sorry for being so vague, but without pics Its obviously really hard to determine whether they are concrete or clay tiles. Im just assuming they are not concrete as the age does not fit.

We have some sort of old cement slate looking shingle tile in Aust. Only seen it once though.

Would have loved to have seen a pic.

phil.

[Bill Kibbel]

Im just assuming they are not concrete as the age does not fit.

I regularly come across concrete roofs original to buildings built between 1910 and the late 1930s. A large majority are the French style tile.

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They've all had completely exposed aggregate. It's usually large-grain coarse sand or really small stream pebbles. Some cracked, broken, loose, tar patched and missing tiles needed replacement, but I've never had a concern that the entire roof system is going to fail anytime soon. The only major issue is really cosmetic - the wear after 80-100 years has significantly eroded the original surface pigments.

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[thomop]

Originally posted by thomop

Im just assuming they are not concrete as the age does not fit.

I regularly come across concrete roofs original to buildings built between 1910 and the late 1930s. A large majority are the French style tile.

These tiles in picture are commonly know as Atlas tiles here.

The were pretty common here around 1930s for the their cost effectiveness.

They are/were a very weak and brittle tile. Often not worth restoring.