I've got a wooden chalet on a site in Somerset. The site wifi isn't the best but since I put Kingspan wall insulation in the signal has dropped, no doubt thanks to the foil on each side of the insulation shielding the signal. The only way I can think of to improve things would be to have a outdoor aerial connected to an indoor repeater. The site is very strict on aerials, not even a TV one is allowed outside so I'm looking for suggestions with a small discrete aerial.