What glass to use? 2

[TheJohn]

Hello everyone,
I'm hoping some of you could give some advise in the right direction.
I'm looking to build a porch overhang with a glass roof. I have done a crappy quick sketch in paint to illustrate what I'm saying.

I'm thinking of using 6x6 posts for the frame and notching the top supports out 1.5" on each timber to support the glass panels.

There are 3 panels measuring at 6x6 , 8x6 & 10x6

I live in northern canada where we have some pretty harsh winters. I'm concerned about the snow weight, hail and extreme cold temps we get. I'm not sure if glass is right or plexi might be better however I'm not sure.

I'm wondering what thickness of glass or similar material I could use for this project to satisfy my needs.
thank you.

 

[Guest262653]

Have you tried the following link?

http://www.hireapeng.ca/

 

[MikeHalloran]

My first thought was that I wouldn't make it flat,
because even if you can get glass to support itself over
the spans that you've proposed,
which is unlikely, you'll go crazy with
water leaks and/or rot from pooling water.

You're basically talking about a sunroom, perhaps with open walls.
A quick search on "sunroom Canada" without the quotes
produced a bunch of sources for custom and pre-engineered
sunrooms, some of which might meet your needs.

It's not the sort of thing I would do without a professional engineer's participation.



Mike Halloran
Pembroke Pines, FL, USA

 

[JAE]

I'm wondering what thickness of glass or similar material I could use

Depends on the type of glass, environmental factors, local code requirements etc. Hire an engineer as the others above have suggested.



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[drawoh]

TheJohn,

I have a skylight installed in my backyard shed here in Toronto. It is sturdy and waterproof and fairly custom as I recall. They did some clever engineering to make it work. It was fairly cheap. I can look up the manufacturer. There are a bunch of people who do this.

--
JHG

 

[BUGGAR]

The Graduate: "Plastics, my boy, that is the future." Lexan.

And enough dollars to make it thick enough not to sag too much.

 

[JAE]

Transparent aluminum works great too!


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[canwesteng]

If you made them vertical, you wouldn't have to worry about snow load or the self weight either!

 

[DeleteriousPhases]

a ten foot span of glass seems very expensive. I'd have to break up the forces and see if you have enough support, i'm not sure that you do just at first glance. but good luck with the project, post what material you decide to go with!

 

[TheJohn]

Thanks to everyone so far for responding with your comments. I'm considering clear polycarbonate sheets due to there strength over glass. Still have to figure out if they could hold the weight without breaking or buckling.

 

[MikeHalloran]

Polycarbonate is crazy strong,
but you have to be really careful what you use to wash it.
Even a short exposure to many common chemicals
can cause a brittle fracture with no warning
at some later time.


Mike Halloran
Pembroke Pines, FL, USA

 

[drawoh]

TheJohn,

My backyard shed skylight is not flat. It is bulged outwards quiet a bit. Also, it has two layers of clear material, providing you some thermal insulation, and they have done a clever job of configuration the sides to make it watertight.

Are you building a greenhouse?

--
JHG