CONCRETE BASE - ADVICE GRATEFULLY RECEIVED

Now advice like that is what I was after

 

I'm totally ignorant of building (although I did a lot of research for the summerhouse) but that's why I thought a sub base of MOT Type 1 might just be sufficient. If it's thumped down to just get a firm level base it should carry a raft OK. Maybe followed by a layer of the polystyrene type insulation and the DPC. Then the concrete and some screed before you put your flooring on top.

Zigs' quote is a possible problem as I'm having problems with crows making a terrible mess on the summerhouse doors and ripping out the plastic stops in the top of the door hinges! (Actually, it's just one crow doing it whilst the others watch! Reminds me of the Council workers around here ) Your cats may deter them.

 

I like that, Kristen.......................so be it..ii

Agreed. I've been through all the alternatives and I've been really grateful for the suggestions put forward. The primary worry for me is to ensure a stable, vibration free platform, that won't move over the years, for the telescope. The Loft proposal is a good idea but obviously has it pro's and con's like all the alternatives and suggestions. One of the main problems for me would be the disturbance and noise with the House during the conversion and the need for a really solid floor for a tripod/pier.

I think that one thing follows the other, Kristen, and the fibres do both. I need to find out if I can get it supplied either as ready mix or if the Builder will have to mix it in his self. I do like the idea as it will negate the need for mesh or Rebar.

So a question still really unanswered is if I put down a slab of concrete 8 feet by 8 feet, with a depth of 12 inches, of which 8 - 10 inches will be above ground level, do I need footings and if so how deep??

I've joined Cloudy Nights, Astroshed and Astronomy UK, so that I can research all sorts of information. I did ask the question on Astroshed and Astronomy UK but the responses were to push me towards installing a pier straightaway, whatever base I constructed, despite my thoughts that I would like to experience using a capable tripod and then later perhaps bolting in a suitable pier. They didn't seem to impressed that I wasn't in favour of installing a pier while constructing the base. I didn't ask the question on Cloudy Nights as I was immersed in reading all the different accounts of building an amateur Observatory of all kinds and sizes. Then, this week, they went "off air" while they upgraded the software and the site. It came back on yesterday but has gone off air again for "maintenance" ......which probably means there's a few bugs in the new system.

 

Just retried it and they're back on air again.

I'll have a think about that, Kristen. The bolts used for the pier are 200mm [nearly 8 inches] which I why I propose a 12 inch depth of concrete.......I would have thought that they would have been sufficient.?? I probably will install a pier but I would like the freedom to try a heavy duty GOTO GPS tripod first and then let everyone say "I told you so!!" when I decided to go for the Pier.

Going on your experience I will probably do the same. I also want an nearby hard standing area to be leveled off and concreted so I will order for that as well which will keep the Builder happy with extra jobs. I don't mind spending money on getting the job done well.....better than going cheap and ruining it.

True, but I'd rather it stayed level and didn't become a Tourist attraction liking the Leaning Tower of Pisa

 

Not worried about it being pretty, Kristen, so long as it does the job!! I''ll do some research on it.
I've also decided to get a bigger scope [a 12 inch Newtonian with a rotator ring system and a right angled finder........I'm fed up of getting a crick in the neck] Just working my way through "The Urban Astronomers Guide" and "The Backyard Astronomers Guide" using the "Pocket Sky Atlas" to navigate around their tours.

 

Painful could be right if I were to keep lugging a 12 inch scope in and out of the House as a Newtonian is 5 feet long and weighs 22 kilos without the mount!!! I'll use the 8 inch scope over the next 12 months until the Observatory is up and running and I've got everything right. Then probably we'll have a year of complete cloud cover!!!