19 replies to this topic

[astrobeast]

Hi All,

 

In a post from a few days ago I was inquiring about vibration issues for a non-piller mounted scope but it brought up another issue that I wanted to start a new post on to hopefully get broader input on whether this is fundamentally just a bad idea, or have others managed to make this work in some fashion.

 

I'm looking to mount a telescope in the attic above a house where I would modify a section of the roof to allow it to slide back, or otherwise create an opening for the telescope. Someone mentioned thermals from the roof as well as coming up through the opening from the inside that could make any high power viewing problematic. As I'm mainly interested in solar system objects for this scope (house is in a fairly light polluted area), this is of key concern.

 

A few aspects of the design concept.

 

1) It would be at the souther edge of the roof line, i.e., the lower boundary of the opening would be just above the eves., so the view to the south would not be looking over the roof. The southern exterior wall of the house would however, be effectively right under the airspace just in front of the optical tube.

 

2) The attic is finished and heated space, so I would need to basically build a room around the scope in the attic that was heavily insulated.

 

So is this just madness, or can this be made to work? 

 

Rick

 

 

 

 

Edited by astrobeast, 30 May 2020 - 01:43 PM.

[Sandy Swede]

Long-time rule for roofs: Never cut a hole in one.  Ask anyone who has a skylight.  Also, if your space is not air conditioned, it can get hot enough in the summertime to do real damage to certain plastics, electronics and anything glued.  How about building an observing deck on the back of the roof with access from a window.  Definitely do not want to have it show much from the street.  You may still have to deal with thermals.  However, most of us here on CN would hold your beer and egg you on. 

 

Madness?  Why heck no.  "You go down there, general."  https://www.youtube....GAdzn5_KU&t=12s

[astrobeast]

Long-time rule for roofs: Never cut a hole in one.  Ask anyone who has a skylight.  Also, if your space is not air conditioned, it can get hot enough in the summertime to do real damage to certain plastics, electronics and anything glued.  How about building an observing deck on the back of the roof with access from a window.  Definitely do not want to have it show much from the street.  You may still have to deal with thermals.  However, most of us here on CN would hold your beer and egg you on. 

 

Madness?  Why heck no.  "You go down there, general."  https://www.youtube....GAdzn5_KU&t=12s

Yes, I am well aware of the rule about cutting holes in ones roof, LOL!

 

I have been thinking of a deck or platform built just off the edge of the house but it would be in view of the street. To locate it in a less obtrusive spot would have it looking over the full roof.

 

The reason for the roof mount is mainly to get above trees and other obstructions. From the ground, I have to move the scope around depending upon where I want to look. I'm not moving it far, but it would sure be nice to just walk up the stairs in the house and be up and running. 

 

There are some other hybrid options, but wanted to see if I needed to rule this approach out first.

[db2005]

Building a shed with a removable roof in your back yard would almost certainly be a lot cheaper, work much better and won't damage your roof.

 

I vaguely recall hearing about a rather excentric acquantance of one of my friends friend who actually did cut a hole in his roof for his telescope (this was probably 40+ years ago). But as - the story goes - it didn't work out too well.

[astrobeast]

Building a shed with a removable roof in your back yard would almost certainly be a lot cheaper, work much better and won't damage your roof.

 

I vaguely recall hearing about a rather excentric acquantance of one of my friends friend who actually did cut a hole in his roof for his telescope (this was probably 40+ years ago). But as - the story goes - it didn't work out too well.

No argument on the cost advantages of a backyard ROR !  The prime reason for doing this is to gain elevation. The view from ground level has too much obscuration, necessitating moving the scope around the yard. Also, we are contemplating making some addition to the house so I would have folded this into that effort.

[Tropobob]

Long-time rule for roofs: Never cut a hole in one...

I wish I had heard of this rule a long time ago ...  It would have saved me much grief. 

[Peterson Engineering]

My dome rests on a raised deck.  Lowers the trees.  Reduces ground thermals.  And I happily loan my chain saw to neighbors.  Here's a construction detail.

 

  

 

Got 2 friends with decks built out off the back of their garages.  Both at least a good 10' high.

[astrobeast]

My dome rests on a raised deck.  Lowers the trees.  Reduces ground thermals.  And I happily loan my chain saw to neighbors.  Here's a construction detail.

 

  

 

Got 2 friends with decks built out off the back of their garages.  Both at least a good 10' high.

Thanks for the response.

 

My problem is I really need to gain about 2 stories of elevation to make a significant difference, i.e, would eliminate the need to change locations to get most of the southern sky. 

 

My garage is buried under one tree and there is a very large one to the south, so while using the garage as a starting point would have been the logical choice, it doesn't really work. Unfortunately, the house occupies the best spot in the yard  . I need elevation right where the house is. 

[MalVeauX]

Heya,

 

If you build a raised deck with a cinder block pier filled with concrete and rebar up the middle, you'll have a stable pier platform as tall as you want it with a raised deck as high as you care to build it. Leave your setup on the pier, with a TG365 cover on it. Ready to go. More like a "tower" than anything. No issues with your house. Inexpensive really to make. Total control over height and surface area to work with. Kids would die to play with it. Obviously needs a good rail system for safty. Think of a "shed on stilts" type build. Your choice if it has a roof or not even. Think of a basic observation tower like for a hunting blind, but with a larger deck and a concrete pier rising up the middle.

 

Plan D... well, move the trees....

 

Very best,

Edited by MalVeauX, 31 May 2020 - 11:01 AM.

[astrobeast]

Heya,

 

If you build a raised deck with a cinder block pier filled with concrete and rebar up the middle, you'll have a stable pier platform as tall as you want it with a raised deck as high as you care to build it. Leave your setup on the pier, with a TG365 cover on it. Ready to go. More like a "tower" than anything. No issues with your house. Inexpensive really to make. Total control over height and surface area to work with. Kids would die to play with it. Obviously needs a good rail system for safty. Think of a "shed on stilts" type build. Your choice if it has a roof or not even. Think of a basic observation tower like for a hunting blind, but with a larger deck and a concrete pier rising up the middle.

 

Plan D... well, move the trees....

 

Very best,

Unfortunately, Plan D requires my neighbors to do the cutting (short of a very fortuitous storm  ).

 

I had considerer the raised deck, but the only viable location for it is in a very exposed part of the yard, so while I probably don't need a permit, I'm not sure the locals would appreciate the appearance. I may be able to build the raised deck off one end of the house - essentially where the standalone raised deck would go - which is probably the best alternative in terms of making something that more organically blends in with the existing structure. Not building an enclosure, just the scope mount with a TG365 cover would probably be the best approach in terms of not making the "appendage" look to out of place.

 

Now I'm sort of thinking about this in real time as I type this. The decked attached to the side of the house without a shed may workout better than I had originally thought. Need to head outside this pm and think this through a bit more.

 

Thanks for the suggestion!

[gdrabs]

Just completing an observation platform as Marty describes. I had no choice but to build between my house and neighbours because the front and back yards are covered with trees. The platform is designed to have a pier running up through a cut out in the floor at a later stage. This will seperate my new HEQ5 mount from the platform and keep things steady for future imaging.

 

Graham

 

 

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[gdrabs]

I'll be planting a creeper to cover the lattice safety barriers to help make the platform disappear from view.... so it looks basically like a trellis.

 

Graham 

[lambermo]

I put a dormer with a sliding roof piece of 2x2m on my house with an insulated room below it a few years ago. Very happy with it. But I don't do planetary.

 

 

-- Hans

[astrobeast]

I put a dormer with a sliding roof piece of 2x2m on my house with an insulated room below it a few years ago. Very happy with it. But I don't do planetary.

 

20141121-sliding-hatch-rooftop-observatory-placement.jpg

 

-- Hans

Hans,

 

OK, what you've done is the closet to what I'm contemplating. Would like to discuss more, if you would. You can respond here or send me a PM and we can chat.

 

Thanks for this post!

[speedster]

Back to the question of thermals.  Your roof certainly has thermals that your backyard does not.  However, your whole neighborhood is a heat island and wherever you look is going through your, or your neighbor's thermals. 

[StormyViews]

Hello everyone. This thread is closest to a question I have. I am in the process of design for a bunkie (guest cottage) at the lake which I intend to incorporate a rooftop observatory into. I fully realize the benefit of a pier system for stability and vibration, but my location will not allow a pier as it is a .82 acre property ringed by 40’-50’ trees, a rather large cottage, and septic field.

 

As the bunkie will sit on bedrock level to the second floor of the main cottage and will itself be two story, it gives just enough height to clear a good number of the surrounding trees and give a decent enough open sky which is not possible at ground level.

 

My intention is to put an observatory (leaning towards a NexDome at this point) and my primary interest is astrophotography, both planetary and deep sky, with a Celestron EdgeHD 14 scope. I’ll likely automate everything so it can be controlled from the main cottage to lessen any vibration walking around might create.

 

My question is what can be done to minimize vibration as much as possible? Wall construction will be 2x6 and rooftop likely 2x12, do I have any hope at all that this will be sufficient, and if not what can be done to make it so?

Edited by StormyViews, 24 September 2020 - 11:03 PM.

[DJL]

YouTube brought me this earlier this year: https://www.youtube...._Yzq4MLYoOdPT4Q - Dome installed on roof.

[StormyViews]

That lead me in the right direction, thank you! I couldn’t get the link to open, but I did find another YouTube video where it was done, 3 years ago, though there were no posts after showing how well it worked unfortunately. I’ll keep searching. Thanks!

[*skyguy*]

Twenty years ago I built a rooftop ROR observatory over my attached garage. It has a 13" pier using 16"x16"x8" chimney blocks. The pier was placed directly on the concrete floor ... no separate isolated foundation. I've never had any vibration problems while imaging with a wedge mounted 12" Meade LX200.

 

I used oversized roof vents and fully vented soffits along the observatory and garage roofs and the inside stays very cool all summer. Thermals coming off the roof have never been a problem because the building is well ventilated.

 

I wouldn't hesitate to build another garage rooftop ROR obsevatory.

 

OrbitJet Observatory:

 

https://www.flickr.c...57644177074161/

 

 

[StormyViews]

That looks pretty sweet! Are those two 2x14 main beams and 2x10 used for the floor of the observatory?

My complication is in a desire to not have a pier system. With the diagonal alignment of the main cottage to the lot, it limits prospective spots for my build. I can only choose to have the pier interfere with the internal layout of the guest cottage and the visual lines within, which we don’t want, and we don’t have the space to do it outside as that means increasing the footprint of the build beyond what we have space for, so I’m compromising by reinforcing the build of the cottage and making the equipment remote operating to eliminate movement vibrations. It leaves wind really as the biggest factor, unless of course I have guests within.

 

I plan to take care of thermals by using closed cell spray foam insulation and thicker than normal walls and roof than is typical for the area here. With Winters hitting temps in the -30 C. and lower range here, that is a factor too.

 

I plan to chronical the build process on YouTube, right now I’m just getting ideas on the best way to support everything before meeting with the architect.

Edited by StormyViews, 28 September 2020 - 12:49 PM.