Adding a loft to a shed

Username John

Hello all,

On the back of the shed thread started By Vander, I started thinking about adding a loft to a shed I put up last year.

My plans were :
add a 15' x 15' loft, in one corner of the shed. I had planned to do this by putting in one RSJ in the middle of the shed, to make a 15' square with a steel 'pole' at each corner (the other 3 would be the railway lines holding up the roof)
Then run 2 horizontal RSJs between 2 of the (vertical) railway lines at say 7' height.
Then run timber joists on top of the 2 horizontal RSJs, and marine play on top to make a floor.

It all seemed simple in my head, until I started looking at what weight would be on the loft.
I calculated that I could put about 200 bales of hay up there. 200 could be stretching it, but we'll say 200 for the weight calculations.
200 bales hay at 20kgs each = 4000kg = 4 ton! :eek:

So - now looking at my plan, I am not sure it'd work? And I have lots of questions...
- What size joists should be used, and what space between them?
- Is 15' too long a span for timber joists, if they're carrying this weight?
- If so, how should I go about it?

Said I'd throw it out there, see what people thought.

I should add I havent done the sums on this yet - I guess get a plan that am confident will stay standing first, then see about costs.

Maybe there are some engineer-y type folks out there who could tell me easily whats the best way to go about this?

Thanks.

cjpm

How are you going to connect the RSJ's to the railway rails?? Not easy, and there'll be a lot of pressure on the connection too.

If i were you i'd set up a 30ft horizontal RSJ bolted on top of 3 RSJ's which are vertical and set in concrete approx 8 - 10ft from the back of the shed. Then build a 7 ft wall, block on flat along the back of the shed between the railway rails 30ft long and then span the timber between the back wall and RSJ. Thus the span of your timber is only 8-10 ft

An 8 ft span might be better as then you could buy 16 ft timber and cut in half.


A 15 foot span is pushing it for a timber joist which is well loaded.

Muckit

Username John wrote: »

It all seemed simple in my head, until I started looking at what weight would be on the loft.
I calculated that I could put about 200 bales of hay up there. 200 could be stretching it, but we'll say 200 for the weight calculations.
200 bales hay at 20kgs each = 4000kg = 4 ton! :eek:

Then there's the weight of the steel and the timber in the loft itself ....:rolleyes:

Shoving square bales into a loft...... now there's a blast from the past. Lovely when you're shoving in the last few on a hot summer's evening under the galvanise and there's not a puff of air out :D... and I suffer from hay fever!!!!!! Then out to the fields to bring in the last load of 'light' bales from around the headlands and throw em up with a 2 prong fork....

pakalasa

...don't forget the hay lice. Christ I hated them. :mad: They only seemed to be there some years, in wintertime too.

Username John

cjpm wrote: »

How are you going to connect the RSJ's to the railway rails?? Not easy, and there'll be a lot of pressure on the connection too.

If i were you i'd set up a 30ft horizontal RSJ bolted on top of 3 RSJ's which are vertical and set in concrete approx 8 - 10ft from the back of the shed. Then build a 7 ft wall, block on flat along the back of the shed between the railway rails 30ft long and then span the timber between the back wall and RSJ. Thus the span of your timber is only 8-10 ft

An 8 ft span might be better as then you could buy 16 ft timber and cut in half.


A 15 foot span is pushing it for a timber joist which is well loaded.

There is a mass concrete wall 5ft high along the 'back wall' we'll call it.

A 30' long loft, 8' wide is prob better...
Well, tis much better really. Easier, and prob better for using the shed as well, as you could still get under it with a loader for cleaning it out, etc if you wanted to...
Not sure I'd get the same number of bales into it, but if tis a case of ensuring it doesnt collapse on top of me head, twould prob be worth it

So - next set of Q
1) As there is a wall there up to 5ft - could I use a heavy 15' joist 2ft above it, but support it regularly, say every 2 feet?
Just be easier than building up the wall thats there now (as the board for the sheeting is bolted to the top of the wall, plus all the sheeting nails, so would be a pain to move)

2) What size joists would I need in this scenario, and how far apart? I know where I could get a heap of 8' x 6" high x 2" wide planks. Would these do the job?

Thanks CJPM.

Username John

pakalasa wrote: »

...don't forget the hay lice. Christ I hated them. :mad: They only seemed to be there some years, in wintertime too.

What are hay lice? Never heard of em?

cjpm

Username John wrote: »

There is a mass concrete wall 5ft high along the 'back wall' we'll call it.

A 30' long loft, 8' wide is prob better...
Well, tis much better really. Easier, and prob better for using the shed as well, as you could still get under it with a loader for cleaning it out, etc if you wanted to...
Not sure I'd get the same number of bales into it, but if tis a case of ensuring it doesnt collapse on top of me head, twould prob be worth it

So - next set of Q
1) As there is a wall there up to 5ft - could I use a heavy 15' joist 2ft above it, but support it regularly, say every 2 feet?
Just be easier than building up the wall thats there now (as the board for the sheeting is bolted to the top of the wall, plus all the sheeting nails, so would be a pain to move)

2) What size joists would I need in this scenario, and how far apart? I know where I could get a heap of 8' x 6" high x 2" wide planks. Would these do the job?

Thanks CJPM.

No hassle John

To be honest if I was you i'd def build it up with blocks. It's way easier than any other way of supporting the timber. Also you can put the timber at any spacing you like and build between the timber to make the boards solid.

1 - You could just move the board outside the poles, build the wall and bolt it back onto the wall. I know it might be out a few inches but what harm.

2 - Or else just bolt it back on top of the higher wall and cut the sheeting.

Option 1 is easier i think.

Then again your idea should work too. Might save you some hassle.


As for timber

I'm not sure how far apart should the boards be if they are 6" high.

In a dwelling the joists are normally 9" high at 16inch c/c

Then again 8 foot is not a huge span.

Maybe you could put them in at 12 inch centres or 9 inch if you were putting a big load on it. The smaller the spacing the more solid the marine ply will feel under foot.

pakalasa

Username John wrote: »

What are hay lice? Never heard of em?

They were little brown lice (If I remember right). If you were anywhere near the hay you'd get covered in them. They were so small you'd just about see them on your arms.

Figerty

Oh you have suffered...but I can give you a worse one than that...

A neighbour of mine decided to make bales of hay (cocks) Trams... so we baled the trams as they came.. on the hotest day in July and muggins here had to build them up.

I never, ever, want to see a square bale again. The weight of the bales was about 1-1/2 times normal and then add in all the stuff you mentioned.

Lost about a stone weight,, dehydrated for a week..

Muckit wrote: »

Then there's the weight of the steel and the timber in the loft itself ....:rolleyes:

Shoving square bales into a loft...... now there's a blast from the past. Lovely when you're shoving in the last few on a hot summer's evening under the galvanise and there's not a puff of air out :D... and I suffer from hay fever!!!!!! Then out to the fields to bring in the last load of 'light' bales from around the headlands and throw em up with a 2 prong fork....

Bizzum

cjpm wrote: »

As for timber

I'm not sure how far apart should the boards be if they are 6" high.

In a dwelling the joists are normally 9" high at 16inch c/c

Then again 8 foot is not a huge span.

Maybe you could put them in at 12 inch centres or 9 inch if you were putting a big load on it. The smaller the spacing the more solid the marine ply will feel under foot.

The father is a carpenter by trade. 9"X2" at 16" centers and braced is more than enough for an 8' span.
No need to go for marine quality ply either, it's a woeful price.

cjpm

Bizzum wrote: »

The father is a carpenter by trade. 9"X2" at 16" centers and braced is more than enough for an 8' span.
No need to go for marine quality ply either, it's a woeful price.

He's considering using 6" boards, so 16" centres is pushing it if it's loaded.

You are def right about the marine ply, not needed at all.

John, keep an eye on donedeal for used ply and and 30ft of 10" x 5" RSJ

The 3 columns don't need to be as big as the beam.

cjpm

Jeez John, you're in luck.

17 sheets of second hand 8X4 in Monaghan!! And it's T and G too.

Prob a bit too far away from you.

Donedeal.ie

Username John

cjpm wrote: »

Jeez John, you're in luck.

17 sheets of second hand 8X4 in Monaghan!! And it's T and G too.

Prob a bit too far away from you.

Donedeal.ie

Am based in Cork, so tis a bit far away all right CJPM.

Thanks for posting it tho, if twas closed to home, twould be good.

cjpm

Username John wrote: »

Am based in Cork, so tis a bit far away all right CJPM.

Thanks for posting it tho, if twas closed to home, twould be good.

Got you mixed up with John Galway! Sorry man.

There's a scrap yard in Little Island. Might be worth a few visits in case you'd get your steel.

Figerty

I have thought about doing this, as long as I could get the tractor underneath.

My Local Shop has done something similar, I'see if I can get a picture. they made one mistake.. another four inches higher and they could have got the forklift under it.

4 tonne weight is nothing to worry about as it would be a distributed weight rather than a point load. For safety when, you have made your 15 by 15 square with the RSJ, you could put another RSJ accross the middle (at 71/2 foot) to support the middle of the floor, this should elimiate any loading concerns

You plan below is pretty sound. Get brackets made to bolt on to the railway pillars. Do not trust a weld for a support. Welding steel railway tracks isn't easy especially for structural work.

Username John wrote: »

Hello all,

On the back of the shed thread started By Vander, I started thinking about adding a loft to a shed I put up last year.

My plans were :
add a 15' x 15' loft, in one corner of the shed. I had planned to do this by putting in one RSJ in the middle of the shed, to make a 15' square with a steel 'pole' at each corner (the other 3 would be the railway lines holding up the roof)
Then run 2 horizontal RSJs between 2 of the (vertical) railway lines at say 7' height.
Then run timber joists on top of the 2 horizontal RSJs, and marine play on top to make a floor.

It all seemed simple in my head, until I started looking at what weight would be on the loft.
I calculated that I could put about 200 bales of hay up there. 200 could be stretching it, but we'll say 200 for the weight calculations.
200 bales hay at 20kgs each = 4000kg = 4 ton! :eek:

So - now looking at my plan, I am not sure it'd work? And I have lots of questions...
- What size joists should be used, and what space between them?
- Is 15' too long a span for timber joists, if they're carrying this weight?
- If so, how should I go about it?

Said I'd throw it out there, see what people thought.

I should add I havent done the sums on this yet - I guess get a plan that am confident will stay standing first, then see about costs.

Maybe there are some engineer-y type folks out there who could tell me easily whats the best way to go about this?

Thanks.