Found this document on how to build an observatory

[kirkster501]

http://www.astrosoft.co.uk/Articles/Build%20a%20roll-off%20roof%20observatory.pdf

Rather than build it from scratch though does anyone have  a conversion guide or know of a thread about what to do to remove the roof of an apex shed and convert it into a run off roof obsy?  I am seriously looking into taking this route .  Anyone got any ideas about converting it so theres a flap on say the south facing side so it drops down a foot or so to expose more sky?

Thanks, Steve

[Tinker1947]

There's one main problem with sheds if its a ready made then its almost ready to fall to pieces, a handmade takes longer but will last a lifetime and the option you want  like a flap, roll off roof can be built in, bite the bullet and make one or get someone in to make it.......

[JamesF]

There are a few things with that design that I'd not personally be happy about and would change.

First I'd have some diagonal bracing in the frame.  I know the shiplap will give some resistance to shear forces, but I think good bracing would be better, especially if you live somewhere windy.  I'd probably also have some horizontal noggins in there too.

I'd also not have runners cut into timber and facing upwards.  Water will surely end up sitting in there one way or another and cause rot.

And I'd not use a clear roof.  It does massively improve the light in the obsy, I agree.  I'd be concerned about the possibility of sunlight getting onto an uncovered objective though.  No matter how much you swear blind you'll always cover the OTA or put the objective cap on or park the OTA facing north, one day you will forget.  And that day like as not will be one that turns out sunny...

That said, I also doubt the sense of converting a flat-pack type shed.  The walls are not up to taking the load of a rolling roof (nor holding it down in a strong wind), so you'd end up having to reinforce the side walls.  Usually the roof is also just two flat pieces of OSB, so you'd also need to rebuild the roof to be able to carry its own weight and have rollers.  The floors are also rarely up to carrying the kinds of point loads involved in supporting "comfortably-proportioned" astronomers (not that I'm saying you are such, you understand so that would need reinforcing as well unless you were building onto the ground.  By the time you've done all that the only original bits are the end walls, and not even that if you want a flap at one end.

Stick-building a rectangular box in timber really isn't hard, nor even that time-consuming given a few appropriate tools.  The hardest bits are the ones you'd have to do anyhow, like getting the rolling roof sorted.  I'd definitely say build it from scratch.

James

[rwg]

Having done it, I'd definitely recommend the build-from-scratch approach, I'm also not sure about that guide - certainly don't follow it blindly. In addition to James' reservations I'd be worried about the corner uprights - a lot of the strength looks to come from those being set in the ground, but fence posts set in the ground do rot over time - do your best to keep timber off the ground completely if possible.

I've built 2 or 3 commercial sheds over the years too and they're always wobbly things until the roof goes on (and even after, to be honest). With the roof detached you would certainly need big-time re-inforcement to be sturdy enough to hold together (and of the roof itself to survive detached from the walls).

The cladding worked out to be the most expensive part of my build, although I could have gone with the thinner 12mm rather than 16mm shiplap. Framing wasn't too bad - main frame timbers were 63*36 treated CLS with the smaller frame components made from tile battens which are treated and dirt cheap.

You can follow the history of my build here : http://www.astronomyshed.co.uk/forum/viewtopic.php?f=35&t=19209

cheers,

Robin

[Gina]

I too recommend building from scratch.  Not only will it be stronger but you have full control over the dimensions.

[RCompassi]

I built an observatory using those plans!

Check it out the outcome:

http://stargazerslounge.com/topic/220886-eimer-sternen-observatory-build/

[r3i]

Hi Steve,

Interesting find.  

I'd have to agree with everyone else that doing it from scratch would be best in the long term.  By the time you've added reinforcing beams and worked out how to convert one side to accommodate a flap for the south side, you would save neither time nor money.

As Gina said, doing it yourself gives you full control, no need to compromise, and you'll have the satisfaction of being able to stand in your garden with a big grin on your face and say "I built that"

[kirkster501]

Thanks for the replies all.

Seems making my own is the way then

I was going to set the whole obsy in a gravelled area at the side of my house. I was going to this in a way such that four (or maybe six) main posts to the obsy went into the ground into concrete (with loose gravel around the top) hiding the concrete and set the peer set into the ground in such a way that I could move the whole thing if I move house my just sawing the main uprights off below ground and unbolting the pier from the concrete block, again set just below ground surface.  I do not want a large concrete slab above ground level.  When I move home in a few years any concreting needs to have gravel thrown back over it to leave no sign of the obsy.  

What about using those metal spikes that fence posts go in and concreting them into the ground - again a few inches below surface level - so the wood is not in the ground?  or what about bitumen over the end of the post before concreting in?

Steve

[Tinker1947]

I put 9 posts (4" X 4")  4' in the ground and just filled in the gap around then with pea shingle, if you want to move the Obby any time just suck the shingle out with a industrial hoover and lift the posts out of the ground, treated before they go in the ground they will not rot as the shingle allows them the breath and stay dry.....

[r3i]

What about using those metal spikes that fence posts go in and concreting them into the ground - again a few inches below surface level - so the wood is not in the ground?  or what about bitumen over the end of the post before concreting in?

HI Steve,

That's exactly what I did with mine - I used a decking kit as the base floor for the observatory.  The kit came with 6 anchor posts but I added another 4 for each corner of the deck just to be on the safe side.  Pics of my build are on my website (link in my signature) and also I had a build thread here: http://stargazerslounge.com/topic/168972-yet-another-observatory-build-thread/?hl=%20yet%20%20another%20%20observatory

I was of the same opinion that I didn't want a massive concrete slab in the garden.  Another advantage of this method is that you don't have to worry about levelling the ground if you have a slope as this is taken care of when you affix the joists onto the upright posts.

As for when you're ready to move house, someone on this site in a previous discussion suggested a cunning plan for making the pier base 'disappear': dig a hole next to it that is big enough and deep enough for the base to be pushed over into and then buried with soil over the top.