Three tab shingles vs architectural vs strip

I am going to have my leaky, 2.7"/12", 20 year old, three tab asphalt shingle roof redone, so I have been trying to educate myself on what I have and what to replace it with.

In So Cal we get occasional wind with our rain and it blasts the west side of the house. It looks like that the main failure of my roof is that many staples on the west side have rusted right off allowing shingles to flap up by the wind. The holes in the tar paper left by the rotted staples are probably the main source of leaks. My shingles don’t look that bad and would probably have gone at least a few more years if they had just used galvanized or stainless staples. I notice that the staple placement is usu no more than 1" from these slots which form a natural channel for the wind blown rain. All in all these three tab seem like a pretty poor design for something that’s supposed to shed water.

If I understand this right, a three tab shingle is a perfectly good waterproofing material that someone has gone and cut slots in for cosmetic reasons. Is there any other reason for these slots? The architectural shingle is somewhat better, but there are still slots (gaps) where the shingles butt together.

I noticed down at HD I can buy these 3ft wide rolls of shingle material. It isn’t going to look like a shingled roof, and you would have to deal with lots of exposed fasteners, but talk about easy. What I am leading up to is why isn’t there a shingle type that is just one continous roll of shingle width material? Just roll out 50ft at a time. It has got to be faster and better waterproofing than the slotted stuff. They could even use the coloring techniques to give it the slotted/shadow appearance, or just make it two layer like architectural shingles.

I am not a roofer so this may be a bad idea for reasons I am unaware of. What do you think?

what you are talking about does exist. its either called 1/2 lap or 90# rolled roofing. it is made for low slopes (which is what you have). it will give you a life expectancy of 5-7 years. in the past few years they have invented a peel & stick rolled roofing…GAF liberty or certainteed flintastic. the areas in which you will run into future leaks on a low slope product are going to be penetrations (vents) or flashing details (where a low slope meets a steep slope or a wall) if you are going to try to tackle this yuorself go to the manufactures website and study, study, study…or hire a roofer.

Why wouldn’t this rolled stuff last just as long as shingle? I would think it would be made of the same material.


It is made of the same materials.

Your car bumber is plastic. So is the wraper on your meat.

Its the seams that are the problem. That stuff is supposed to be used for valleys only. If it was me i would use a peel and stick style of material. 3 ply system. Base, mid and cap sheet. its around 160 dollars a square if you are installing yourself. It is like the 90 pound but is designed just for the low slope like yours. Shingles will not work they will trap water on a 2/12 i would not do it.

The seams in the 90 pound with the open faces of nails will not last long. It is the half {blank} way of doing it. Also it will look terrible. That style of roof normally on that pitch in a snow area will only last a couple of years if that. If you are selling the home you will be losing money on the repair since any good inspector will know that is not the proper way of doing it.

hire someone to put on an EPDM rubber roof. very few (if any seams) depending on the size of the roof.

Marshall on a 2/12 dont you think epdm might be a little agressive? ANd pricey

Hi gtp1003,

Why would shingles not work?

You are telling someone who has shingles on their roof, for the last 20 years that it will not work. He is replacing a 20 year old shingle roof.

What do you mean by edpm is a little pricy? It is probably obvious, but I missed it.

anything 2/12 or under i usually rubber. i trust it more than peel & stick or shingles on a low slope. less seams and it should last at least 20 years.

They dont reccomend shingles at 2/12 fromwhat i have learned over the years. I see so many like that and they leak like a siv.

I think in tns1’s first post he was talking about regular one-foot-wide shingles, and why they couldn’t be marketed in roll form instead of three-foot lengths.

I’m guessing that rolled shingles would be hard to package, more prone to damage, and not as stackable as flat bundles.

From what I understand these roofs were designed for hot-mop style of roofing, and maybe they were all that way originally. Now I think there are maybe 4 out of 50 that have this. Most are 3-tab or architectural. What some have done is to use 3 layer underlayment with the shingle instead of 2 layer, and I would definitely do that if I go with shingle.

Back to my great contribution to roofing technology. Imagine taking a bundle of the two-layer architectural shingles (no slots), joining them together end-to-end and putting it on a plastic spool. Provide a two inch adhesive end lap to eliminate the few butt joints. No exposed fasteners and no slots. Just roll out course after course of this stuff. Alignment should be a non-issue, and it looks just like the best shingle.

Now this would probably only work for low pitch like mine, but hey it should last as long or longer than standard shingle and be quicker/easier to install. The hollow spools would take up more room than bundles, but you could sling them across your shoulder like a bandoleer for hauling up the ladder leaving both hands free. Do the shingle butt joints provide for expansion? Would a roll of this stuff be more likely to ripple from temperature expansion or does it stay down once its nailed?

So I ask again is this the foundation of a roofing empire or are there serious flaws here?

this is all nice and quaint gentlemen. like, just talkin bout whatever.
you know i get upset when i have to work here.

mr tns1,
let e explain.
you probably have a three tab shingle on your house for a reason.
it probably doesnt have much slope, and those cut outs your talkin bout are very important . they allow the water which lays heavier on the lower slopes, to not get trapped, under the shingle were they but together on the sides ( ends ).
if you go puttin a convensional two peace demsional shingle, without those cut outs , on your low slope, youll be sorry. they will let water in.

one other thing to look for, is a spotted sealant strip ( the tar strip that seals the shingles together ). a solid sealant strip will let water travel sideways and leak in, where the spotted sealant strip lets water dump
yes in heavy rains water gets in the sides of all shingles.
the lower the slope the worst it gets.
its smart to put a flat roof system on your low slope.
and no, not roll roofing ( 90 lb).
im goin to pretend i didnt see that metioned here.

i have spoken.


i wasnt recommending 90#, i was simply telling him that was what he was describing. and what the life expectancy of it is.

my appologies,


ice&water shield entire deck(w/proper ridge&soffit venting),and use 3-tabs to maintain the pitch,dimensionals can cause water ponding due to the double thick shingle bottoms-it will never leak during the roof life(warranty period)