Attic Antenna with Radiant Barrier (foil) on Roof Sheathing

[R7000]

Hey group, we are planning a new house. Modern construction appears to be using this foil radiant barrier roof sheathing. I'd like to hear from anyone who has this and came up with an antenna solution for VHF/UHF, and HF.

Can you cut a "window" in the foil for the antennas to look out of?

The house I'm in now has my VHF/UHF ants in the attic and I get great results. Wondering about the future with this radiant barrier.

The radiant barrier can be avoided if you use spray foam insulation under the roof sheathing, but our builder won't use it because it masks potential roof leaks.

Ideas?
Thanks

 

[bw415]

I have no experience with the roofing foil but I would suggest just trying an antenna up there and see what happens. I’ve been into radio since 1968 and many times I have been told this or that type of antenna won’t work. I have tried them anyhow and sometimes they do and sometimes they don’t. I have learned not to trust other people’s opinions and just go for it and see for yourself.

 

[RFI-EMI-GUY]

I would be curious to get a sample of that barrier and wrap a radio or cellphone in it to see if it is conductive. Maybe put a corner in the microwave.

As far as insulating under sheathing. Spray foam is not recommended by shingle companies as it causes heat to build up in the shingles. As far as radiant barrier, if there is an air gap created by the trusses that allows convective air to flow from eaves to the ridge vent, that is probably OK. You might consult local experts, perhaps a university extension that has tested different methods.

 

[merlin]

If the barrier is metalized, it will relly limit your reception. Pull some of it down so your antenna is above it.

 

[prcguy]

I have that in a mountain cabin and it’s a shield to RF, you would have to cut a huge hole for an antenna to work.

 

[wtp]

you are living under the microwave.
and if they did that on the roof the walls are covered too.

 

[G7RUX]

You could certainly cut a slot in just the foil and use that as a slot antenna…however I would be wary of using any significant power into an antenna made of foil.

 

[bharvey2]

My house doesn't have the radiant barrier roof sheathing but it does have foil back insulation in the walls and ceilings. I can confidently say that it has hinders RF activity inside the house. When we first started using wi fi devices ( the wife and I have lived in the house for decades, predating the modern computer and wi fi era), I even had to install multiple access points in order to cover the entire house. If a repeater or other radio isn't fairly close to my house, communication is pretty tough without an exterior antenna.

 

[JvdK]

If it’s a nice big attic, you could consider to place a dormer on it. That will improve your reception and you could turn your attic into a radio shack 😁

 

[R7000]

I got a couple of samples of the radiant barrier from different makers. The foil can be removed pretty easily. It wouldn't be hard to cut a window in it for a VHF/UHF ant. The dormer idea is a good one too, thanks JvdK.