Thread: New Shed build

Originally Posted by Arch Stanton

I now have my permits and the shed kit is lying on the front lawn. It looks beautiful.

I've downloaded my 117 page instruction manual and am reading it for about the 5th time. I've had plenty of blokes in my ear telling me which way to build it. The manual does point out that there is more than one way to skin a cat.

I've decided to follow the method the manual suggests and will build it on pads and pour the concrete slab afterwards. Before I start I have to level the site and then I'll get the bob cat guy to drill the footings.

Being a first timer there is a fair bit I don't know so I'm going to throw a few questions (easy for those in the know) to the floor. I've been googling for 2 days but am still in the dark.

1) How far above the ground level, which will be a garden bed with mulch, should the Colorbond be? 70mm

2) How high above the ground level should the top of the slab be? I've heard numbers ranging from 10mm to 50mm but figure that with the pad dimensions and the clearance needed for the Colorbond that the floor will be about 100mm above GL. 100mm with a thickened edge beam around the perimeter but check with the engineer first

3) How thick should the eventual concrete slab be where it sits on the pad? Is 25mm enough? It is a 10m x 8m shed and I'm assuming I'll have a 100mm thick slab at this stage. If you make the pads exactly square and all the same level, make the pads the same height as the finished slab BUT fit expansion joint around the pad before pouring the slab (prevents cracking)

The build will start in the next few weeks and pictures will follow.

Arch

+1 for RW'S advice.

If the shed look beautiful lying on the ground just imagine what it will look like
when assembled!!!

My shed was pretty much constructed that way as well, with the slab being poured last.

One thing to think about, and what I picked up from my brother’s mistake, (bless him) is to ensure the slab is slightly higher than an abutting path or driveway concrete section.

Also, I had the concrete slab part dropping towards the entrance of my two roller doors and point of entry swinging door. The drop starts about 200mm from the edge. The roller door rubber seals on my doors hit the deck 110mm in from the slab edge; this allows a further 90mm of continuous slight drop from inside.

My brother didn’t do this; one of his doors (mine as well) faces south and cops the full brunt of the weather. The result is that he gets pooling water inside when rain is hitting the door, I don’t.

Mick.

As others have said above.

Some pics might help you.


This is Pads poured - with portal frames laid out ready to erect.


Portals stood and Girts & Purlons on


Cladding process.


Slab in & consider whether you'll insulate the roof


Trims on - roller door hung etc.

When you do your set out, you MAY have to allow minimum set backs off your fence...(Depending where your building it on the block).

If its near a side or back fence or both, and say the local govt authority (shire) specify a minimum 1 meter setback....then consider that when positioning your pads - you have to allow roof and gutter overhangs (150mm?) extra.

So if the wall sheets would come down at 1 meter - you'd only have about 900 clearance to the gutters from a vertical line up from the neighbors fence - which technically is not to spec.

That's why You should allow a little more if working to minimums from the fence.

Also when you measure your distance away not all blocks corners are square - they frequently aren't so you may have to allow more or less depending whether the property line intersection is obtuse or not.

Lastly also allow that the fence may bow inwards... in the middle say. e.g. When setting mine out I initially allowed 1 meter at the back corner - then 1 meter at the front - off the fence before pouring the footings etc but after I had formed up... my supervising builder... checked everything - and measured from the center of the wall of the shed to the fence - it was only 980mm coz the fence wasn't 100% dead straight where a tree branches and roots growing in the neighbors place had pushed it offline by 20mm into our place.

I was able to crib the wall over 50 mm to account for this on my concrete pads.. to get away with it (but my gutter technically is too close) because i tried to work with the minimums 1 meter.

If I were to have done it again - I'd have allowed say 1150...clearances.... so the minimum 1 meters allowed wasn't an issue.

You always earn something.... from the build process.

I built a 2nd shed for someone else (to help raise funds to finish mine) and allowed for my mistakes on the first one, when doing the second one saved a lot of headaches.

Hopefully you could learn something from every member who's been down this particular path of shed building.

There are lots of potential traps along the way - its basically pretty simple. The manuals don't always cover everything.

Presumably you will be running power (Water?) to this shed? Sewerage connection if you have a loo in it?

I spent inordinate time sorting all this after the fact (Bobcat guy dug up old reticulation - which wasn't an issue but also some of the current retic - and I was chasing pipes everywhere, capping them off where they went under the shed, re routing them around the shed and re connecting and some solenoids were involved (and the wires connecting them) which meant finding the solenoids in the lawn and re - wiring them.

I fortunately had a plan of the latest retic layout - only - the solenoids were no where near where they were shown on the plan in actuality...so they took some finding.

There's always thing you don't bank on...when you start that can trip you up and slow you down...

You'll find them all throughout the process - are there for example old soak wells anywhere under the area your intending to build - that later sewer connection have made obsolete but they are still there but not back filled? Will you hit the drywell/soakwell concrete lids when you start digging to form up your concrete pads?

All traps for the inexperienced...

Hope it goes smooth for you.

Cheers

Another suggestion only - You don't HAVE to do this, I did.

When you (drill) form up your pads.



About a week before I started, we had a tornado rip thru our suburb about 100 meters away from our place.

It literally demolished a few double brick homes to ground level... (like you see in the US tornado belt aftermath pics)

I had suffered one many years before down in the country. It was a direct hit on a shed I build (10 x 10 meters)!

The shed was about 150 meters from our house on the farm. When the tornado hit the shed our house shook so violently (middle of the night) it woke us all, and we thought it was a earthquake. When we got up in the morning, the roof and parts of walls etc was gone from the big shed.
It was like someone had bombed it.

I found the remnants of it a mile away on a neighbors farm... upside down.

Some of the 4 x 4 Jarrah Wall Posts were still attached to the roof - including the 600 x 600 concrete pads and galv stirrups they were attached too - pulled clean out of the ground!.

In the same paddock - there were 250 - 300 year old Jarrah trees 40 meters tall twisted off half way up the trunk... diameter of the trunks 1 meter!

Unless you experience a weather cell event like this first hand its hard to understand the forces of nature. Having lived thru a few cyclones up north as well ) I am under no illusions now.

It as this life experience that made me determied to make sure nothing but othing was going to lift THUS shed out of the ground. A Pitched roof in 100mph + winds creates terrific wing in ground effects that want to make things lift - look at the weight fo jumbo jets that will fly laden with hundres of people and 1000s of liters of fuel etc.

It cost me considerably more $ (maybe $800) for the extra steel pipe and concrete - to "over engineer" my pads...to give them extra holding down power into the ground with the 8 inch diameter steel reinforced "legs"...

Hopefully it will never be needed.

But if it is - well i did the best I could to prevent anything being ripped out of the ground.

By shaping my pads into "pyramid shapes" 50mm smaller at top than bottom, when you pour your slab around them - IF they were to lift they key into the slab and lock.... In theory it shouldn't be possible to pull those pads up thru the slab because they get bigger towards the bottom. (550 x 550 at top 600 x 600 at bottom).

If I as contract building sheds for a living I would never go to that trouble or expense or time.

Having lost a good shed once (And finding out later our insurance had lapsed because we were a few weeks late with the annual premium) I decided to make an extra effort this time round.

Your mileage might vary....

You don't expect Tornado's at 32 and 34 degrees south - but they seem to seek me out and follow me around so I don't take chances any more.

It's just a suggestion - fell free to ignore it.

Cheers

2) How high above the ground level should the top of the slab be? I've heard numbers ranging from 10mm to 50mm but figure that with the pad dimensions and the clearance needed for the Colorbond that the floor will be about 100mm above GL. 100mm with a thickened edge beam around the perimeter but check with the engineer first

Once the shed is built I was just going to get a concreter in to do the slab. Do you have to have an engineer look at it?

3) How thick should the eventual concrete slab be where it sits on the pad? Is 25mm enough? It is a 10m x 8m shed and I'm assuming I'll have a 100mm thick slab at this stage. If you make the pads exactly square and all the same level, make the pads the same height as the finished slab BUT fit expansion joint around the pad before pouring the slab (prevents cracking)

I'd better do a neat job on the footings if my work is going to be exposed.

Originally Posted by Optimark

One thing to think about, and what I picked up from my brother’s mistake, (bless him) is to ensure the slab is slightly higher than an abutting path or driveway concrete section.

Will do. Path will be at ground level and as it appears that the slab will be 100mm thick and the walls 70mm above ground level. That will mean that the Colorbond will have a 30mm overhang on the pads and that there will be a 100mm step up to the shed.

When you do your set out, you MAY have to allow minimum set backs off your fence...(Depending where your building it on the block).

Will be OK here. I'm on a big block and I'll my measurements off the verandah. Will make sure all is square.

Timeless, they are serious foundations. Not having your experience with the weather I wont make my pads as heavy duty as yours. My plans call for pads 450mm x450mm x 450mm. The building inspector said it was all about the mass and I think I'm right in saying that in this instance bigger is better. I'm going to ask him if it is alright to make them 450 diameter and about 600 or 700mm deep. I'll square them off at the top where I make the form work but below that I want to get them drilled out. I haven't spoken to bob cat man yet but hope he has something like a 450mm auger.

Originally Posted by Arch Stanton

Will do. Path will be at ground level and as it appears that the slab will be 100mm thick and the walls 70mm above ground level. That will mean that the Colorbond will have a 30mm overhang on the pads and that there will be a 100mm step up to the shed.

When you do your set out, you MAY have to allow minimum set backs off your fence...(Depending where your building it on the block).

Will be OK here. I'm on a big block and I'll my measurements off the verandah. Will make sure all is square.

Timeless, they are serious foundations. Not having your experience with the weather I wont make my pads as heavy duty as yours. My plans call for pads 450mm x450mm x 450mm. The building inspector said it was all about the mass and I think I'm right in saying that in this instance bigger is better. I'm going to ask him if it is alright to make them 450 diameter and about 900mm deep. I'll square them off at the top where I make the form work but below that I want to get them drilled out. I haven't spoken to bob cat man yet but hope he has something like a 450mm auger.

And the slope out at the doors is excellent advice, quality builders always do this with the doors into garages

I'll just watch.

Here is the shed and the shed site at present.

Next step is to get bobcat man in to level site. While I am doing that I need to go shopping for new tools. I need a new drill cement mixer and other assorted items.

Have the bobcat guy teed up for wednesday.

The plan is to mark out the site on monday and then he can come and scrape the area and dig the footings or else dig the footings and scrape the site.

I'll then do some some form work for the footings. They have a step down design so I'm working out how to box them up. If I watch a bit of youtube on step building I should be right.

I've still got half a dozen blokes telling me the best way to build a shed and they are all different. I've nearly been persuaded to change my approach but am still looking at doing it according to the instruction manual.

When it comes to pouring the concrete for the footings I will probably hire a concrete mixer and do it myself. I thought about getting the truck of ready mix but have crossed that off the list. I have very little experience with concrete and I want to have plenty of time to pour the footings.

Good luck with the DIY concrete, dont forget to do your slump test and get a compression test done. Very important that your mix meets the required standards.

Originally Posted by rwbuild

Good luck with the DIY concrete, dont forget to do your slump test and get a compression test done. Very important that your mix meets the required standards.

Thanks Ray.

You're a wealth of information. The slump test is another thing I'd never heard of before. It looks eay enough to do.

New plan.

I'd been thinking about the shed for the past 2 years and had it all planned out. The bob cat guy is booked for Wednesday.

My mate came around today and has convinced me that I haven't chosen my site very wisely. The upshot is I'm going to be walking around the block tomorrow scratching my head and going over his idea. What he said made a lot of sense. The shed was going to be close to the house and would detract from the house's visual appeal. I'd also gain more outdoor living area. I'd originally based the shed size on the available space, 10.4m x 8m. In the new site I will have room to extend in the future.

I'll have to finalise this new idea tomorrow or else I'll have to cancel bobcat man until I get it sorted.

I'll also have to look at the shed plans and see if I can reposition the PA door. I think I can.