Anyone install metal roofing?

[keegs]

There's an air channel by way of the standing ribs in the metal roofing that runs from the rake up to the ridge. I know there's a ridge cap seal installed on my roof but it doesn't block the flow of air as the seal overlaps the metal roofing between the ribs and cap but doesn't seal the open end of the ribs.

Someone mentioned to me that there's a rake seal that would somehow seal this open air channel but I can't find anything on it.

Anyone have any experience installing metal roofing?

 

[om21braz]

My father installed one, against popular suggestions, over the top of shingles. He capped it only - no seal in the areas between each rib, the cap sitting atop the raised ribs running perpendicular to the ridge. It did not have a ridge vent prior to installation of the metal roof, it does have gable end and soffit venting. Been on approx. 15 years now without any issues. His is a simple 4 corner house though. IMHO, it depends upon your climate to determine the use of a vent at the ridge.

 

[magicheater]

These roofs have been installed for over 50 years with no problems. A good quality silicone caulk would work if you are that concerned about air flow which would be minimal and since it is outside your attic space would be of no concern, unless I am missing something.

 

[rswyan]

These roofs have been installed for over 50 years with no problems. A good quality silicone caulk would work if you are that concerned about air flow which would be minimal and since it is outside your attic space would be of no concern, unless I am missing something.

The OP's post has me wondering too .... it sounds like he's trying to seal it up for some reason ...

I'm not really sure why you'd would want to that ..... he mentions a ridge seal cap ... on my polebarn I actually have a ridge vent under the entire length of the ridge cap .... buildings need to breathe ....

My parents actually had someone come in and cut additional holes in the soffit (which was plywood) for vents at their home due to inadequate attic ventilation ...

 

[richamor]

It sounds to me like he wants to cover the bottom end of the channel on the metal where it meets the boxing.
I asked about that when I bought mine and was told no, there isn't anything to cover that end.

 

[keegs]

These roofs have been installed for over 50 years with no problems. A good quality silicone caulk would work if you are that concerned about air flow which would be minimal and since it is outside your attic space would be of no concern, unless I am missing something.

cluster flies...http://en.wikipedia.org/wiki/Cluster_fly

My theory is that they're getting into the attic via these rib forming channels. I think they roost in the channels during the night.

They show up in the attic in the morning after the sun comes up and the roof warms.. They arrive in the thousands. By early evening they disappear. It seems to be a problem during spring and fall where we are in Maine.

I spoke to the roofing supplier and he told me to shoot some canned foam in the channels at the rake end.

 

[richamor]

Is there no screen over your ridge vent?

 

[keegs]

There's a flexable foam seal between the metal roofing and the ridge cap but this foam seal doesn't seal the open ends of the ribs. The ridge cap covers the ends of the metal roofing ribs but the seal doesn't.

As is usually the case, a few inches of the wood sheathing is cut away from the ridge, leaving a passages from outdoors (via the these rib channels) into the attic.

Another point of entry could be the ridge cap ends too. I don't know if there's a screen or if the foam seals the ridge cap ends.

 

[Carl_NH]

I have a metal roof on my barn with 3' Wx20'L sections that was installed over purlins on the rafters every two feet. The roofing stops about 1" short of the top and then a ridge cap is installed over that.

What also came with the roofing were preformed foam strips that emulate the ridges in the roofing. I think we got two per sheet with the metal. We did not install these, however I beleive they are for sealing the rake/soffitt area on the bottom where the metal/trim intersect.

I dont think sealing the ridge / top is needed but I can see sealing the bottom edge to prevent bugs or etc coming in.

 

[magicheater]

I think I misunderstood the type of metal roofing that was being discussed. I was referring to standing seam roofing and I believe the op was referring to the other style of metal roofing. Insects are a problem, we have asian beetles by the thousands in the fall and they crawl in everywhere.

 

[richamor]

When my roof was installed, they put down a fine mesh screen over the ridge vent opening and tacked it to the roof sheeting. The paper, metal, and ridge cap went on over that. I don't see how anything could come in through that, unless there was a hole in the screen.

 

[WVBill]

There is a foam rubber seal for the bottom edge of the panel. It is flat on the bottom and has a peel-off adhesive strip on the flat edge. The top edge has the profile of the panel. Each strip is as long as the panel is wide (3').

When I ordered my metal roofing from Fabral, I ordered packages of the sealer strips. I just happened to notice at Lowes this past weekend that they carry the same - or very similar - strips in their roofing section.

You can buy ridge cap that is either just plain metal or the same but with a "foam mesh" bonded to the under-side. The mesh "seals" to the profile of the ribs and keeps bugs out at the ridge but lets it vent.

 

[skipmarcy]

The metal suppliers sell boxes of the foam strips configured to the contour of the metal, the strips have a mild adhesive on one side so you can stick it to the sheet before installation. I did not use them as I wanted as much breathing as I could get. I also covered my ridge with screening to keep critters out before I put the metal and ridge cap on. Has been fine now for 5 years....

 

[Robert_in_NY]

As a few others have stated already there is a foam strip available for metal roofing to close in the bottom (it sticks to the drip edge) and the top (it sticks to the roofing and the metal ridge cap is anchored on it to compress it). In our area the advantage of the bottom strips is mainly to keep bees and bugs out of the ribs and building. The top strips keep the bugs out as well but also help build a dam to keep water from backing up under the ridge cap on high winds. Water travels up hill much easier on metal rooms then on shingle roofs and one of the biggest complaints we have in this area with metal roofs is water coming in through the ridge. Anything up under the ridge cap will usually help keep water out and that includes the honeycomb type ridge venting.

 

[keegs]

So do I understand it that this rake end seal, seals up the air channels formed by the ribs that run up to the ridge cap?

 

[2manyrocks]

Yes. They sell a foam product that is contoured to the shape of the metal panel that will close up between the ridges on the panels, and it is not so cheap.

Shooting can foam--1) can make a real mess and 2) be sure to use the door/window product that isn't supposed to bow out whatever it's blown into. The other stuff could push out your roof. I'd be leery of using it.

If it's just a bug issue, why not remove the ridge cap, install a bug screen, reinstall the cap and call it a day?

 

[keegs]

Getting up on that shiny metal roof could be a bit dodgey I think...

I can stick my finger through the cut-a-way sheathing at the ridge and feel the rib channel, so I could conceivably stuff the channels with something but I thought some kind of seal at the rake might be a better solution.

 

[valley]

Wifey and I installed corrigated metal over asphalt about 9 years ago. We get as much or more snow than anyone in this world. I am pleased with the metal, have it on the barn and bunkhouse also.


Richard

 

[Patriotic Stabilist]

Hubby hired 2 guys to help him. He took off all the decking, repaired some rafters and replaced a couple. There was one huge piece holding up the roof over our family room. It's over 30 foot each direction with no support in the middle. We have a hip roof, so he put a huge beam up there that did the trick.

While he had the roof off, one of the guys and I insulated, the rooms didn't have the insulation out to the edges of the rooms and we added insulation there was no insulation about 1 or 2 ft in some places in each room, no way to reach it. He also added more ventilation. We have never had termites but while we had it off I bought termicide and sprayed it between the brick facing and black stuff. We haven't had spider problems in the house since, I really hosed it in there.

Then he redecked with Techshield and a metal roof on top. He ran bug screen down the vent in the top. We didn't get the foam for the ends, it was too expensive. What he did was buy some filter material and stuff it up all the ends to stop the bugs. where each panel overlapped we bought the sticky tape that you peel off and put on them, place the next panel on top and screw down. And the techshield is awesome stuff. You can go in our attic on a day like this, its hot and you wouldn't want to, but before you couldn't even go up there. He figured it lowered the temp in our attic 30 degrees or more. With our house and the garage we added we covered around 2600 sq ft, cost about $10k, but hail had destroyed our roof and we had replacement value, so that helped with about $3k of it. I had a rough estimate to do all that around $20k, so even paying help we came out ahead. It was a lot of work but we now have a 50 year roof. While he was at it he rebuilt the soffits too. We have 2 foot overhangs all around our house which helps keep it cool also.

 

[dave1949]

cluster flies...

What's up with those dang things? They crawl out of the seams in vinyl siding on warm days in April on the sunny side of the building. They had to have spent the winter there I think.

I don't buy the theory that they parisitize earth worms in their larva stage, we have millions of flies and very few earth worms.

I am thinking of spraying my attic space with a permethrin-based insecticide this summer. Some of those are persistent enough to kill on contact for a week or so after spraying. I'm getting tired of hearing my garage attic buzz like it is possessed every Fall :laughing: I can hear them thru 18" of fiber glass insulation and chip board ceilings.
Dave.