Topband: Aluminium roof vs antenna performance

[Grant Saviers]

I had a 40m and 80m top loaded vertical on galvanized steel roofs. The 
80m was outstanding for DX and the 40m so-so since the roof was not well 
bonded electrically.  IMO, unless you can insure electrical connectivity 
along the panel seams there will be no advantage to the foil.  You would 
probably be better off with a good radial field under the poly foam, a 
small gauge wire will work if you put up 50 or so radials and you could 
staple those to the roof sheathing. Then you could extend that radial 
field with some elevated radials if space permits.

Grant KZ1W


On 10/18/2013 9:26 AM, Riccardo Negro wrote:
> Hi all,
> tomorrow I must decide which type of insulating system to be used under the
> tiles of my new roof. Roof's structure is classic wooden and total surface
> is 220 square meters.
> Since there will be several antennas for 80 / 160 sorrounding the house I
> am wondering if using insulating panels (polystyrene) covered with a foil
> of ALUMINIUM (to reflect heath) could become a nightmare for antenna
> resonance, pattern, etc.
> The point is: better to have or not to have a roof with aluminium under the
> tiles ?
> Many thanks for your kind advice !
> 73 de Rik, IK2CAW
> _________________
> Topband Reflector
>