However you should be aware that with Digital Switchover on its way soon, a loft aerial is usually not much use for Freeview.
Unless you are VERY close to the transmitter, Freeview needs a good, correctly aligned outdoor aerial.
T, April 2009
Relatively easy.
Much will depend on ability to get up there - familiarity with and access to hand tools - attitude to dust and spiders (there won't be many) and lighting. You should obviously take care to stand on the wooden rafters rather than between them.
Peccavi, April 2009
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I can answer this question...
How easy is it to replace a TV aerial in the loft?