Thread: New shed - owner build vs shed company?

Hi Ross,
My experience is limited in the fact I haven't built my shed yet but I am electing to owner build my shed based on the shed companies cost to erect the shed. I was quoted $10,300 for the construction of 16m x 7.5m, 3.6m high gutter hight. They quoted $13,500 for the slab (including excavationon level site) but that would likely be increased due to the actual site gradient etc.
The kit is $20,000 which includes the following: class 10a, wall and ceiling insulation, roof wire (NSW requirement), roller door x1, sliding glass door, 2 x windows. Takes them 3 to 5 days to erect with 2-3 people.

I paid a drafting company to draft $1600 and do council application ($2000 application fees). I plan to outsource the excavation, slab, electrical and plumbing. I will be paying a mate $30ph to help me construct the shed. I own scaffolding and all tools for the job (I think).

Like you, I have building experience which I think makes it worthwhile considering owner building.

When working out whether it's worthwhile owner building you have to factor in; If you can make the time without too much financial loss from leave from work etc. $150 owner builder course, $1,200-$1600 relevant insurances. Equipment hires for erecting the shed.

As well as savings on constructing the shed, as an owner builder I think it is easier to keep the cost down on The additional cost of running services, water tank, stormwater, stormwater overflow pits, landscaping, electrical, plumbing, excavation etc. As you can shop around for quotes and DIY where practical.

I think in the end it comes down to what you can afford and whether the savings are worth the fuss.

Cheers

Ross
Most shed companies have contractors they can put you in touch with to erect the shed.
I wouldn’t go mixing up who is sheeting the walls with a different trade doing the roof as they all get put together in a mixed sequence
If you want to save money just get seperate contractors for slab, and other trades and either take on the shed erection and cladding or contract it out.
I am a builder and I still thought it was worth while having it erected by others and only ended up doing it myself as I couldn’t wait for the installer to come.

My shed extension was only 6x4m and I was going to do it all myself but I decided to get the planning and build done by a shed company. The main reason was that I working flat out AND I knew that just fitting out a new shed to the level I wanted would consume a lot of time and I wanted to have it close to finished for when I retired ~12 months later.

The shed builders did all the council stuff which I was happy to pay for because I had tricky situation that I believed a shed company would get through easier than I could and they did it very efficiently. My new shed was attached to a 5.3 x 3.5 40 year old shed - that shed also had to be seriously renovated during the process. If I had removed old shed new boundary conditions would have applied and I would have lost save.

However I still did a lot of the "other" work although I hired my nephew to help with some of the heavy stuff
- 32 standard limestone block retaining wall to enable new shed to be at same level as old shed.
- 15m^2 of back fill barrowed 60m from front verge downhill thru tight side access to shed location.
- compacted the pad.
- unpacked old shed and demolished internal built in shelving etc
- broke up damaged concrete floor in old shed and barrowed that 60m uphill to a skip on the verge
- organised my own slab contractor and electrical contractor to instal a basic breaker box and lighting/power circuits
- installed my own plumbing and mains gas line.
- Connected new to old shed ie built a steel supporting arch/frame to strengthen opening.
- old shed frame had slumped about 6" in one corner so had to jack up roof and welded in short sections of steel pipe to get the roof level
- reposition door and window location and clad old shed with same Colorbond and new shed.

Fitting my shed took me far longer than I though it would so I was really glad I got the shed built; see BobL's shed fit.
- insulated and lined both sheds internally.
- plumbed reticulated compressed air throughout shed.
- built external enclosure for compressor
- added more breakers and more 10A and 15A circuits
- built a number of new benches, shelves etc (welding table, metal stock rack, 2 lathe benches, large assembly bench, fume hood for welding and spray painting, etc)
- Built an enclosure for a DC and installed 6" ducting dust extraction system.
ETC

Short version is - don't underestimate the fitting out time.

I've been down the American barn route twice now, 16mL x 12mW x 3.8mH side walls (5.5mH ridge line) in Eastern suburbs in 2006, and a two storey 16m x 13m x 5,5m side (8mH ridge line) in Alexandra last year.

For the first one, a concreter mate and some of his gang did the floor for the cost of materials, the kit supplier organised the building permits, plans etc and put me in touch with one of their erection gangs. Erection price was based upon the cost of the kit plus hire fees for a scissor lift for the assembly period. They had 4 people working on the job and it went up in 3 days.

For the second one, my concreter mate was retired so we used the suppliers recommended concreter for the floor and footings (21 off 600mm square x 1200deep and a 150mm floor) and also used their erection gang. While only marginally bigger in footprint the extra height doubled the overall kit weight and assembly price. Assembly gang was an experienced guy, his late teen son who had started working for him six months prior to my job, and a 25yo whose first day was day 1 on my job. Again assembly fee was a percentage of kit cost plus hire of scissor lift and they were working on the job for 10 days.

Both barns came together well and meet my expectations. I would suggest that you need a minimum of 2 reliable crew at all times as a lot of the material can be difficult to handle and move unless you can have someone at each end. For the first barn, all lifting for erection above 1200mm H was done with the scissor lift, and most was for the second one as well, but they used the winch on the guys 4WD to stand the uprights up (250mm x 75mm x 2.5mm thick C channels back to back and 7.2m long) as they exceeded to lifting capacity of the scissor lift.

Experience with the construction style of the supplier helps a lot as well, I was present for the delivery of both barns and was expected to sign for delivery of both (6 and 8 page inventories) and it took a fair time to try and ID all of the members with slight length and punching differences. Erection crews spent 20 mins looking and plans and sorted all the structural stuff in about half an hour because they knew what would have what punchings, be what length etc.

Personally, I would suggest that you would be best to pay for the shed suppliers to do the complete erection and cladding (at least) unless you can muster a reasonable sized gang of reliable willing workers or are willing to spend a couple of months plugging away at it in your spare time. A big issue with the spare time approach is that you really need the scissor lift most of the time to provide a reasonably safe environment for a barn that size, so you would loose a lot of time picking it up and dropping it off whenever you will be working, or still paying for it when you aren't working. My second erector managed a sweetheart deal with the rental company and the ten days hire caught a big (55%) discount of the regular daily rates.

While not specifically talking figures, I have tried to give you some insight into the job so you can compare figures from your supplier with what you believe you can do the work yourself for, and make a meaningful decision based on your circumstances. I believe the approach that I took for both was correct in my circumstances.

Get the shed company to give you a signed copy of the layout plan for the slab, use it to form up and pour Your slab and footings, then have a reputable experienced crew erect the structure and clad it. Before any sheets are screwed on, go around every single connection of the structure, with the leading hand of the erection crew, and inspect it, then when every single bolt and screw is correct in the structure, sheet it off. Make sure all the bracing, including fly bracing of roof purlins ( commonly neglected) is installed.
Also, go and look at another completed shed and slab done by each contractor, ask the owner their opinion of them, if it’s positive, you’re starting off with a good feeling about what you’re going to get. It’s a big undertaking, and should be done correctly and safely the first time.

I'd still be building my little shed, if I OB it. (2009)

Pouring and levelling a slab is not an easy task if you haven’t done one - DAMHIK. I had my slab done by a Concreter and I erected the shed with help from a mate and SWMBO.

Ross have you had much experience in pouring such a big slab? Can you use a troweling machine and freehand with a screed ?
A job like that I would form and steel it and then pay a Concretor to place and finish it.

I’ve owner built two sheds one was a basic 12x9.

I’m with the others suggesting that you get a pro to do the slab. Unless you have access to all the gear (trowels, floats, helicopter, boxing ect) it would be near impossible to do a decent job yourself. If you were to buy/hire the gear it would probably eat up most of the savings. Also it’s a big problem if you make a mistake with the slab, there’s no going back.

As for the rest of it - piece of cake. As long as you got someone reliable to help (friend, family, wife) and time on your side you will get it done.

Do all the council approvals yourself, just get the shed supplier to give you all the necessary engineering drawings ect.

Hire a scissor lift for a weekend and stand all the portal frames and do as much else up top as you can before returning it.

The more you do yourself the more you will save. But just remember that something that takes a pro one day will take you three (or more) so allow plenty of time.

Good luck!

Having been a Plumber Drainer for 49 years and having done 3 OB's myself, I'd be leaning towards your last line
and would be getting the shed company to build it to lock up, and hire in Plumbers and Electricians to do your internal work.
You didn't mention your age, but this stuff is best done by younger backs and they bounce better than us older guy's.
Doing your own slab can be risky, on one of mine, I had a Concretor/ Concreter friend to help with the finishing, beautiful job
so we had a few beers, it rained for 30 minutes. No big deal, screaded off most of the water and some of the slurry and trowelled
it back up again. Rain set in again, so we covered it with plastic sheeting for the night and went to the pub to drown our sorrow's.
The finish was rough and my problem, you get the shed company to do it... it's their problem, and no cost to you..

PS, boy I'd love to have a shed 12m x 9m !

Even the experts get slabs wrong. I organised the crew to do my 10 x 8 metre slab with very deep perimeter footings, got the concrete supplier on site to spec the quantity and finally did some sums myself which differed from the quantity quoted. About 3/4 of the way into the pour it finally dawned on everyone that the amount of concrete was not going to be correct and they had to organise another truck late on Saturday morning from a batching plant an hour away. Words were said and no one was very happy at all. It turned out I was right and the quote was wrong and I got explanation why.

Thanks for all the advice & suggestions.

I will get a price from the shed companies for both options and see how they stack up.

With regard to the slab, I do have a mate who is a commercial builder (retired) so has plenty of experience in concrete work. Alternatively, as mentioned above, I could do the groundwork, formwork & steel & subby out the pour & finish.

Hire of equipment might kill the DIY option from cost perspective - the nearest tool hire company is three hours away from the block of land, so that will add two days to any hire period (six hour return trip).

I'm keen to get the shed up ASAP as it will form the base of operations for the house build, so it may be that the shed company is the best option, even if there is a price premium (the house build I will do as an owner builder).

Be aware that all owner builders in their first build always under estimate the cost every time without exception by a long way. I just did a project and through experience worked out a price then added a large percentage and came out close to budget.

Originally Posted by Chris Parks

Be aware that all owner builders in their first build always under estimate the cost every time without exception by a long way. I just did a project and through experience worked out a price then added a large percentage and came out close to budget.

Absolutely
Apart from not being able to source materials at as good a price in most cases the inexperienced will usually do things out of sequence and inefficiently which doesn’t matter if it is just their time but when it is materials and plant hire or paying for additional labour the savings evaporate very quickly and can often become more expensive than a professional job. In most cases your subcontractors will cost you more than what a builder will pay because of your lack of experience and understanding of construction which ultimately requires more labour from the stubbie which is more spcodt to you.
The property across from me is just starting a new build and their first mistake was they have poured the concrete driveway crossing. They started it the first week of December and only poured it last Thursday. Now apart from them taking close to 10 days with machine hire and roller hire to prepare what a contractor would of done in one or two days max the driveway will be roo ted by the time the project is finished and will need replacing
So first job in the project they are probably 5k to 10k over budget.