Age of shingle roof

[Scott P.E.]

This is a great forum. You guys really know your stuff. My question is how can you estimate the age on a shingle roof? My old house had a 15 year old shingle roof on it and the inspector guessed right when I sold it.

By the way, I am looking for a house and the last one I looked at had PB pipes in it. This forum really gave me the heads up on the problems with it. Thanks

[Chad Fabry]

There is no dead accurate way to determine the age of a roof. I look at the flashings, degranulation, cupping, checking, shingle style and material. Then based on that I make a wild assed guess.

Here's one for you, since you're an engineer. Real 2x10 (old lumber) 16ft span flat and level balloon construction. The room is about 240 square feet and I'd like to use about 3000 lbs of marble tile on the floor and walls. That's about 500 square feet of tile total @ 6lbs each. Do I need a beam? If I do need a beam would cutting the span to 13 feet suffice?

Nice to have you on board,

[Steven Hockstein]

Originally posted by Chad Fabry

There is no dead accurate way to determine the age of a roof. I look at the flashings, degranulation, cupping, checking, shingle style and material. Then based on that I make a wild assed guess.

Here's one for you, since you're an engineer. Real 2x10 (old lumber) 16ft span flat and level balloon construction. The room is about 240 square feet and I'd like to use about 3000 lbs of marble tile on the floor and walls. That's about 500 square feet of tile total @ 6lbs each. Do I need a beam? If I do need a beam would cutting the span to 13 feet suffice?

Nice to have you on board,

Hi Chad,

Marble, like ceramic tiles, is not very forgiving. If the joists deflect, you will get some cracking. If it is not a big deal, add the beam. The deflection will be reduced if you shorten the joist span to thirteen feet.

Good Luck!

Steve H.

[Brian G]

Personally I never try to estimate the age of roofing, but rather how long I think it has left. How old a roof is doesn't necessarily tell you how long it has left, that depends on more factors than age. I'm looking for all of those little signs of the beginning of the end so I can warn my client if they're there.

Brian G.

[kurt]

Beware marble tile on anything that flexes. I've found that marble cracks easily; what usually happens is that you get a "white stress line" instead of a crack due to the soft nature of marble.

I'd stick an LVL in to split the span & stiffen up the assembly. That's a lot easier than tearing out foooooked up marble later.

Oh, yeah, what about the age of that roof? Roofing performs as well as it drains; I look @ 30 year old roofs that look great and 10 year old roofing that is shot. It all depends on the pitch. Trying to tell age from condition is hard or impossible; I usually do some math by figuring out the age of the house & then working backward to figure the roof age.

[hausdok]

Hi,

I think that figuring the age of a comp roof really depends on experience with the products used in your own area and under your own climatic conditions. I've gotten pretty good at looking at the surface of a comp roof and estimating, by percentage, where it think the cover is in its expected service life. Many times I've found out, after I estimate where it is in its wear cycle, that I was either dead on or nearly so in terms of how many years a cover has been on a roof.

The trick though is trying to stay out of trouble when they want to know how long it will last. Again, that takes experience and then you have to give them a good dose of reality and explain that the cover might last that long if well cared for, but if ignored, not cleaned and left with debris on it all the time, don't expect to get nearly that long.

So far, I've had a really, really good record figuring comp and shake roofs. Tile's another matter. I don't see a whole lot of that and when I do I won't walk on it, so I can never really get a really good look at it.

ONE TEAM - ONE FIGHT!!!

Mike

[Jim Katen]

Originally posted by Scott P.E.

. . . My question is how can you estimate the age on a shingle roof? My old house had a 15 year old shingle roof on it and the inspector guessed right when I sold it. . .

If there are Oatey plumbing vent flashings up there, the date is stamped right on them.

Likewise with several brands of plastic vent jacks.

Also, in my area, I can easily tell the age of the shingles by judging the moss crop on the north face. Kind of like counting the rings on a tree stump.

- Jim in Oregon

[Paul MacLean]

Originally posted by Brian G.

Personally I never try to estimate the age of roofing, but rather how long I think it has left. How old a roof is doesn't necessarily tell you how long it has left, that depends on more factors than age. I'm looking for all of those little signs of the beginning of the end so I can warn my client if they're there.

Brian G.

I learned a long time ago to never tell a client how long you think the roof will last. If you say 3 to 5 years, all the client hears is 5 years. Then when the roof starts leaking in 4 years, the client calls swearing you said it was going to last 5 years.

I simply tell them they are going to have to replace the roof "immediately", "in the near future" or "in the foreseeable future." The bad ones get the Walter Jowers tag line..."the sooner the better."

Works for me.

[Scott P.E.]

Thanks guys, good answers.

Chad,

The 2003 International Residential Code Table 502.3.1(2) has required spans for loads. A big factor is in the joist spacing. The wood species and grade is important too. However, making an assumption of a 40 psf live load and a 20 psf dead load total(the tile alone will be 12.5 psf in dead load) you will be in the ballpark with 13 ft. span for SS grade. The table shows a 24 inch joist spacing for 2x10 of Spruce-pine-fir SS grade at 13'-8". I'm sure it probably does not have a grade on it but check the wood closely because only the best quality wood will work. Notching, cutting, and drilling may present a problem too. This is book stuff though, the best advice is from the other guys who have seen the problems.

[Chad Fabry]

16 inch on center, 4/4 pine tongue and groove face screwed to every joist with 3/8 plywood glued and screwed on top of that. (I got a colated screw gun for Christmas)I also glued and screwed 3/8 plywood to the bottom of the joists to stiffen it further.

I don't think they graded lumber 170 years ago, but it's clear pine of some sort and it's from old trees because the growth rings are so close they're hard to count. I'll put in a couple beams on everyone's advice..I can't put one in the middle because of windows and doors, But I can put in one on each side of the openings. It'd look funky with one beam not centered in the ceiling below.

[Steven Hockstein]

Chad,

Sometimes when were are in a bind, we will dress up the structure and create a coffered ceiling using the structural beams and adding some false ones to create a pattern.

Steve