Johnny the scavenger

Yaztromo, Belgarath, Saruman, Dumbledore,Rapunzel, Pug,what have they all got on common? Apart from nearly all being wizards and all being fictional, they all live in towers. Even the Weasley's house is essentially a tower.
Why is this relevant? It's not, I would just like to live in one too. I remember when the government privatised the water board and in the advert there was what looked like a castle turret at the end of a stone bridge, that's where I wanted to live
It was probably a pumping station or something and damp as hell

Yaztromo's tower

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Now my major ambition is to have a shed I can use as a workshop and man cave. Not a flashy technocentric man cave but a rustic comfortable place, a good chair, some music and books and that will suit me fine. I have a slice of garden beside my house that is 5'5" by 14', its the sort of space that collects junk and detritus, at the moment its storing old carpet, old toys and some other large rubbish items waiting for a trip to the dump (it also has two old TV aerials I want to keep for the aluminium that I need to hide from my wife).

As you may (or not) be able to tell from the opening sentence I am a bit of a fantasy fan, a friend at school introduced me to fighting fantasy and lent me Forest of doom, two years later I was playing Dungeons and Dragons in the French classroom at lunch time, a slippery slope began, MERP, Rolemaster, Traveller, Warhammer, WH40k, Tunnels and trolls, Twilight 2000, Maelstrom there may have been more, we got a lot in for three years of lunch times. After school I played with friends and added Spacemaster to the list. I still even to this day play 40k with my kids and sometimes with old friends. Many people distain role-players but I like to think people who play computer games are just role-players with no mates, and nearly everybody has played computer games.

Back to my shed , I have started a wish list on pinterest so I can kit it out when I finally get round to building it. Economy is a major factor, and something not to complicated to build. Lighting I think can be achieved with a couple of solar powered shed lights that are fairly cheap, I don't really need power for anything else except heating and that is proving trickier than lighting. I have found instructions on building solar heaters out of aluminium cans and a glass fronted box but that will only work when the sun is up and winter nights are long here in the northern hemisphere.

I also have an issue with what size to buy, theoretically a five foot wide shed should fit in the space, but how much room do you need around it just to put it up? Does it matter if it touches the side of the house? Will rainwater coming off the roof cause potential problems in the house? Is 5x7 better or 4x9, pent or apex?

I need to do something soon, my wife is getting fed up with me using the kitchen for a workshop