a wee bit of guidance and or "mark my homework please".

[TedOfTheLowerMeadow]

evening all.

see attached my miraculous design of end view of my proposed hair brained lean to extension....

hopefully it's reasonably straightforward.... basically..... existing shed steel upright is 3.45m off deck...... I have been permitted to extend it out 8m....

so.... I need to know.... at a 10° angle..... length of the beam..... and height of the new additional upright to bolt said beam too.


using online tool (within the image)... I got these conclusions.....


looking forward to you good people chastising my homework is a "not quite as brutal" a fashion as our woman do.... when I attempt to do the laundry.....

 

[e3120]

Only comment would be, will your black rafter stop inside the blue stanchion? The length of 8.12m would be from the outside of the red, to outside of the blue, so most likely need reduced by the steel width.

 

[TedOfTheLowerMeadow]

Only comment would be, will your black rafter stop inside the blue stanchion? The length of 8.12m would be from the outside of the red, to outside of the blue, so most likely need reduced by the steel width.

yep. you are correct.

as with most things.... that popped into ma ead' about 0255 this morning.


so.
when using the calculator.... DISTANCE IN LENGTH should of been 8000mm minus the MM of the upright stanchion.

 

[ladycrofter]

Hell of a snow load to hold up over that length . . .

Questions- How did you arrive at 10 degrees? Basically that's a flat roof. 2m high wall at off side not very useful? Just thinking your H beams will be helluva depth over 8m so you'll have almost no headroom there. A quick look says 450mm depth for 8m. Plenty calculators online.

IMO come in a metre or two, easy to be greedy! An apex shed would be better all around, structurally sound amd good outer headroom.

Some shed builder guys on here will be able to advise.

 

[TedOfTheLowerMeadow]

Hell of a snow load to hold up over that length . . .

Questions- How did you arrive at 10 degrees? Basically that's a flat roof. 2m high wall at off side not very useful? Just thinking your H beams will be helluva depth over 8m so you'll have almost no headroom there. A quick look says 450mm depth for 8m. Plenty calculators online.

IMO come in a metre or two, easy to be greedy! An apex shed would be better all around, structurally sound amd good outer headroom.

Some shed builder guys on here will be able to advise.

awesome reply. thanks up kindly.

yep. snow load was something I thought of... then chose to ignore.


we dont really get snow any more in west Midlands. certainly nothing substantial. and besides.... isn't the world getting hotter and hotter ?


the levels were arrived due to where the existing height of building is. existing building pitch is 15° but can't use that pitch as there would be circa 1.5m.


2m is plenty height for that section as I'd use that part for machine store and we don't have tall kit.



i do however think.... what if I moved the stanchion inwards to say 6m. and have a 2m overhang?

that would substantially change the load characteristics?


hmmmmm....


as said. appreciate all input and opinions

 

[ladycrofter]

Yes you would gain more more structural integrity and headroom coming in a few metres, remember you're going to lose well over a foot of useable height from the depth of your H beam. So banging your head putting stuff away in the coombe

Outside covered space is always useful. If you're sheeting the outer wall, run the concrete out and put a big sliding/roller door and a normal door in. 2m is plenty wide to stick bales under, wash down stuff, etc.

Don't discount snow load!! It may be getting hotter but the weather is also getting more unpredictable. I had to shovel a foot of snow off a smaller version of what you're talking about and it was like frozen lead, incredibly heavy. You need at least 40 degrees IMO to get it to slide naturally. Then it's deadly, huge slabs crashing down. I'm old enough to remember the sheds collapsing one winter in Aberdeenshire in the early 2000's IIRC. So . . . Put in the biggest corbels they'll let you!!! The shed designers had thought the same as you and I believe a lot of sheds had no corbels . One guy survived only because he was in his tractor when the roof came down.

 

[upnortheast]

Much more useful space to do a pitch roof. Will need much smaller steel than 8 m lean to.
Downside , will need a valley gutter against your existing shed

 

[ladycrofter]

Gutters on the radio today. The guy was saying the specs are not functional now because we are getting more, heavier downpours. Basically saying houses should have deepflow now.

Those valley gutters have always given me the willies. What happens with heavy snow, piling up, melting and refreezing underneath?

 

[upnortheast]

Gutters on the radio today. The guy was saying the specs are not functional now because we are getting more, heavier downpours. Basically saying houses should have deepflow now.

Those valley gutters have always given me the willies. What happens with heavy snow, piling up, melting and refreezing underneath?

We have some. No problem, just need decent design, installation and a bit of maintenance when necessary.

 

[goldeneagle]

Here's a quick modification of CAD drawing i used for getting our lean to quoted (same angles but 10m wide) just for reference.

 

[Mur Huwcun]

I did a similar one but 7m span with 10degre pitch as a monopitch shed about 6 years ago.

How many bays on yours? Would centre posts be a disaster? Plenty of 30’ lean toos areound here done in 70s and 80s with 7x3s and still ok but not worth chancing now.

 

[deleted user 837354]

Never discount snow loading. I remember some photos on a forum of farm buildings that had not been designed right and they came down in that big snowstorm a few years back.

 

[Rich_ard]

Unless your going in with a cabless machine it will be low. The high end will be low aswell! I have a lean too that's 3.8 at the low end. It's low enough.
What steel are you going to use and purlin?

 

[ladycrofter]

Good point. Measure to the top of your beacon and then some.

 

[deleted user 837354]

Unless your going in with a cabless machine it will be low. The high end will be low aswell! I have a lean too that's 3.8 at the low end. It's low enough.
What steel are you going to use and purlin?

I agree, I should think a shed that is only 2m internal height these days would not have much utility.

 

[Sheep]

What's to the right of the shed? - on the 2m side?