Metal Roof with OTA, good or bad? - AVS Forum

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kstyv's Avatar kstyv
09:41 AM Liked: 10
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03-22-2010 | Posts: 175
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I'm considering installing a metal roof, but I do not want to lose OTA reception.
Anyone with experience with metal roof reception before and after installation, was it better or worse?

Not as impotant but, how about AM signal inside the house?
Scooper's Avatar Scooper
09:49 AM Liked: 17
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If your OTA antenna is outside - shouldn't be an issue - if it is in the attic - prepare to move it outside.
kstyv's Avatar kstyv
10:05 AM Liked: 10
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It is on the top of the roof outsidebut only 2 ft above the roof top.
I do get dramatically different results from summer with asphalt shingles to winter with snow cover. Which leads me to believe the metal will have an affect.
systems2000's Avatar systems2000
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Your antenna would perform at it's best, 35' above the ground level (AGL).

Take a look at HDTV's website.
kstyv's Avatar kstyv
10:59 AM Liked: 10
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Quote:
Originally Posted by systems2000 View Post

Your antenna would perform at it's best, 35' above the ground level (AGL).

Take a look at HDTV's website.

Yes I know, however I will not be moving the antenna, I have already optimized my system and am receiving full signal.

I'm asking specifically about metal roof affects.
AntAltMike's Avatar AntAltMike
11:27 AM Liked: 30
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If the roof is sloped, then the out of phase signals that bounce up and hit your antenna from the underside will be stronger coming off a metal roof than off a shingle one. The magnitude of that deliterious effect will be different at different frequencies.
kstyv's Avatar kstyv
11:47 AM Liked: 10
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Quote:
Originally Posted by AntAltMike View Post

If the roof is sloped, then the out of phase signals that bounce up and hit your antenna from the underside will be stronger coming off a metal roof than off a shingle one. The magnitude of that deliterious effect will be different at different frequencies.

Thank you much, yes is has a standard shallow slope.

Is this why I get better reception when the roof was covered with snow?
jjeff's Avatar jjeff
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Just a guess, but if you have snow on your roof I'd assume it would be winter. If it's winter I'd guess the leaves would be off your trees.
I'm thinking your better winter reception has more to due with the lack of leaves than snow. AFA the metal roof, my guess is it would only make things worse, but how bad is hard to tell. As someone else mentioned the further away you can get your antenna from your roof(metal or asphalt) would be better.
Ideally you'll find someone else who when from a asphalt to metal roof, was in a weaker signal area and also had his antenna a short distance from the roof. I just don't know if you'll find someone like that who'll read your message, otherwise it's just best guesses.
I personally like metal roofs and would be of the mind to put what you want on the roof and deal with the consequences later. You may need a more directional antenna or higher mast but you should still be able to keep your OTA, it just may require a bit of tinkering.
kstyv's Avatar kstyv
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Quote:
Originally Posted by jjeff View Post

Just a guess, but if you have snow on your roof I'd assume it would be winter. If it's winter I'd guess the leaves would be off your trees.
I'm thinking your better winter reception has more to due with the lack of leaves than snow. AFA the metal roof, my guess is it would only make things worse, but how bad is hard to tell. As someone else mentioned the further away you can get your antenna from your roof(metal or asphalt) would be better.
Ideally you'll find someone else who when from a asphalt to metal roof, was in a weaker signal area and also had his antenna a short distance from the roof. I just don't know if you'll find someone like that who'll read your message, otherwise it's just best guesses.
I personally like metal roofs and would be of the mind to put what you want on the roof and deal with the consequences later. You may need a more directional antenna or higher mast but you should still be able to keep your OTA, it just may require a bit of tinkering.

Actually, before I added the research comm preamp, I was struggling with signal, and as soon as the asphalt was showing on about 1/2 of the roof the signal took a dive, and the trees have not yet budded. Yes I have full signal now but my LOS is directly into 2 trees, so I'll see how much loss I have then, hopefully it stays full and I can afford take a risk on losing some signal with the metal roof.

But yes I was hoping to get lucky and talk with someone in the same boat as me. Bad odds yes, heh.
ProjectSHO89's Avatar ProjectSHO89
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Sap rises in trees well before (weeks...) the buds arrive.

It's the increased moisture content in the trunk, branches, and (eventually) leaves that causes the chaotic signals behind trees.

As far as the metal roof, you do need. to maintain a minimum distance from it with the antenna. Antennaweb.org recommends 10' above a flat metal roof although they do not qualify that suggestion by band. 2' is certainly too close.
blue_z's Avatar blue_z
05:01 PM Liked: 18
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Quote:
Originally Posted by kstyv View Post

I'm asking specifically about metal roof affects.

Back in the days of analog a few neighbors installed metal roofs. The ghosts (multipath) required repositioning my antenna. This was like 20 years ago when they introduced metal roofs shaped like ceramic tiles and coated with little stones.
arxaw's Avatar arxaw
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My antenna is on a tall tower away from the house and other buildings. Snow often improves distance TV signals travel and the signal strength of my weaker channels. It's not snow on a roof - just snow on the ground.
ProjectSHO89's Avatar ProjectSHO89
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Quote:
Originally Posted by arxaw View Post

My antenna is on a tall tower away from the house and other buildings. Snow often improves distance TV signals travel and the signal strength of my weaker channels. It's not snow on a roof - just snow on the ground.

Do you think you might be getting an in-phase ground-reflection?
wxman's Avatar wxman
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I have steel siding on my house. I pick up OTA HD just fine with a small amplified indoor antenna. I'm 10 miles away from the towers, which luckily are all the same direction away from the house.
ProjectSHO89's Avatar ProjectSHO89
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03-23-2010 | Posts: 2,755
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Quote:
Originally Posted by wxman View Post

I have steel siding on my house. I pick up OTA HD just fine with a small amplified indoor antenna. I'm 10 miles away from the towers, which luckily are all the same direction away from the house.

Signal is still getting in via windows or, perhaps, the roof. It certainly isn't penetrating the siding.
arxaw's Avatar arxaw
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Quote:
Originally Posted by wxman View Post

I have steel siding on my house. I pick up OTA HD just fine with a small amplified indoor antenna. I'm 10 miles away from the towers, which luckily are all the same direction away from the house.

Distance to towers and co-location makes all the difference in the world. The amp isn't likely doing any good, unless the antenna is on a long coax.
arxaw's Avatar arxaw
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I've read that you should keep at least a 4' distance between the TV antenna and a metal roof.

WRT AM radio, you'll just have to try it. AM's biggest enemy is electrical noise interference from appliances, dimmers and some fluorescent lights. If AM reception is worse after installing a metal roof, you may have to turn off certain electrical devices in the house or add an outdoor AM antenna.
wxman's Avatar wxman
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Quote:
Originally Posted by arxaw View Post

Distance to towers and co-location makes all the difference in the world. The amp isn't likely doing any good, unless the antenna is on a long coax.

The amp does help. if I turn the amp off, no signal. The antenna and tv are on the lowest level, actually partially below ground level. The antenna and tv are on northwest side of house, with towers southeast of house (10 miles). Only one window in that room, on north wall, and I have it blacked out using aluminum foil so there are no reflections off of tv screen. The length of cable from antenna to tv is less than 10 feet. With amp on, always get a solid 70 to 100% signal strength on my pioneer 5020.
arxaw's Avatar arxaw
05:35 PM Liked: 10
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Turning some amps off will block any signal getting from the antenna to the TV.
wxman's Avatar wxman
05:44 PM Liked: 279
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Quote:
Originally Posted by arxaw View Post

Turning some amps off will block any signal getting from the antenna to the TV.

Thanks. That's what I kinda thought. It's an old RCA amplified antenna, over 10 years old, and still does the job.
systems2000's Avatar systems2000
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My CM3020 is probably 15 years old and receiving DTV very well.
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