Yes, an aerial could be installed in your garden or on outbuildings. This will depend on the strength of the signal in your area. A professional aerial installation company will be able to advise you on the possible locations for an aerial on your property.
Isle Of Harris
Harris is the southerly and extra hilly part of Lewis and Harris, the largest island in the Outer Hebrides, Scotland. Although not an island itself, Harris is commonly referred to as the Isle of Harris, which is the former postal area and the current message town for Royal Mail postcodes beginning HS3 or HS5; see HS postcode area. St Kilda, an uninhabited tiny archipelago, located 40 miles (64 km) west-northwest of North Uist is taken into consideration part of the civil parish of Harris. The exact same holds true for the remote uninhabited rock island Rockall, which is 230 miles (370 kilometres) west of North Uist. According to the 2011 Census, there are 1,212 Gaelic audio speakers (60%) in Harris.