Shed extension #5 (Container roof)

The container's new roof had to be strong enough to withstand a tropical cyclone or two and be built by one person. It would help transform the leaky container into a dry hut.

So decided on 4x2" wooden beam rafters to go across and 64 mm steel "top hat" purlins to go on length ways. (This is the method that most of the boat shed roof is built and proved category 3 cyclone proof, 180 km/hr winds). It would take a few weekends and "mid winter" up here is perfect for roofing jobs (16 - 27 C) and no rain.

Recycled materials were to be used as much as possible. So the best thing to look for first is the sheet iron. Found  twenty 12 foot long corrugated iron sheets in good condition at the local recycled timber yard "Full circle timbers" in Townsville, the price was about 1/3 of new sheets (it was $310 for a 3.6 x 13 m roof area). The ute slowly carried the full load a few km to city base, it weighed allot and was up on top of the carry racks so the center of gravity was high.  To go 50km on the open highway to the boat yard i took the sheets up in 2 loads, 10 sheets per trip. 80-90km/hr felt safe enough.

Once the roof sheet length was known, the number of purlins could be figured out. Drew up a roof frame plan. Downloaded a Stramit products table, what design spacing's etc in it for various products. 64mm high galvanized top hat with 1mm walls looked strong enough. 5  purlin's each 13 m long should do it (at around 90 cm centers), so 65 meters of purlin lengths required. This gave about 50 cm of over-hang at the ends.

The 30x30x3mm rafter support posts were welded in place. Twelve needed. One side was 6" and the other side 12" to give a moderate roof slope. "Metalfix" paint converted old rusty steel into near new and protected weld joins.

Welding posts on

Next trip was 4x2" hardwood beams salvaged from demolished "Queenslander" houses. These cost $4.40/meter. So $110 bought the 5 beams of 4 meters or so length each. They went up in one ute trip and joined the single 4x2 already there.

To get them up on the container's roof, the ute tray was rolled in to make a good scaffold platform about 1m high. which just left 2 meters to lift onto the containers roof.

The M10 threaded rods, boxes of gal nuts and washers cost about $40. The 4x2" beams were clamped on then holes drilled for the threaded rod bolts. About 45 cm (2 foot) of beam overhang was made on the low side, the high side was left open to be trimmed off later.

In the tropics ample roof overhangs are important. To keep downpour rains out and also to shade walls from searing sun heat. But with only 4x2" beams and the 12 foot sheets overhangs had to be limited to about 50-60cm on each side. Too much canter-levered overhang in a cyclone probably wouldn't be good!

Another weekend was time to get the top hat purlins. These are hard to find second hand, so new ones at around $7/m were $520 the biggest cost yet. At the steel retail yards they said they don't cut the 6.1m or 7.5m lengths in half to transport on standard ute carry racks anymore. Delivery cost by hire truck and driver would have been over $200.

So a day that weekend was spend fabricating a front carry rack for the Ute at the wylo yard using some scrap steel  laying around.

Started with old 40x40x3mm angles 8" long - these were drilled and bolted to the Toyota workmate (2004) ute's bull-bar mounts with 10 mm threaded rod.

Front rack attachment

Then recycled 3/4" galv pipes were cut and clamped together with wood frames to hold them while angling them and lining it all up on the ute. A partial A frame with a T top resulted, which gave good forward visibility (a vertical post would have sat in the drivers line of sight) and a semblance of sideways stability too. Once the dimensions were sorted it was tacked together, then fully welded. End ears also full welded on. The top cross bar is 0.9 m wide to take long roof iron sheeting if required.

Front rack - semi A frame with T top.

3 racks on ute - carrying 6.1m long top hats

Lashed a pipe fore and aft to brace the front rack in that axis, then went for a road test at 90km/hr. No harmonic troubles or wobbling at top speed. Chose the round pipe as its also an aero-dynamic section. (My first-ever front rack on the 1970 Ford XY falcon in the 1990's was a bit rougher, built with square box sections and angle steel, it worked well but was aerodynamic as a brick.)

So armed with 3 carry racks covering a 5m length of the ute, returned to "Orcon" steel retailers and the "Stramit" top hats were loaded on easily. They weighed 119 kg, so took it easy below 90 km/hr to deliver to the yard. Again the ute tray - scaffold system made it easier to hand lift the top hat purlins up on the container's top.

stabilizing pipe from from rack to cab rack

After use the front rack was quickly removed and hung up on the workshop wall on nails out of the way. (The back rack is also demount-able)

The third weekend's work involved getting the top hats installed over the rafter's. I made a 12 foot long measuring stick (sheet length) , drew up some profiles of the edge details in the office van (could add a barge board and rain gutter later), to figure out the distance between the two outer purlins.

"The boat yard office" 

All the top hats were fastened  to the wood beams with 25 mm wood tek screws. Just the occasional one to locate an hold at first, and later all the screws were sunk with the variable speed drill. To get through the 1 mm steel a small pilot hole was drilled with a second drill.

The lengths were joined with 20 mm steel self drilling tek screws with 30-40 cm overlap. 6.1 m lengths did not quite make the 13 m required so had to add a 166 cm final piece to each purlin length. This extra time and work could have been avoided if  7.5 m lengths were purchased instead.

Outer purlins in place

Next the 3 infill purlin's gaps were figured out, 85 cm centers gave even spacing. Used a red industrial crayon to mark things up, it was very easy to see on wood or steel. The infill pulin's were much easier, faster and safer to fit because of the solid container top to walk on.

13 m long Purlins all in place

Cyclone proofing was to add builder's strap over some of the purlins on the corners and edges of the roof frame. A cyclone could possibly rip a purlin (and whole sheet roof) off with out this extra fastening. It's held to the wood beam by 4 x 25mm wood tek screws. The strap also spreads the loading out over a wider area of purlin.

cyclone strap on top hat purlin

Roofing

Spent a day to get most of the sheet iron on, 12 foot sheets proved to be a manageable size. The first sheet was carefully squared up to the purlins. Used a 1.2 m straight edge and marked screw positions with the red crayon as each sheet was aligned.

Hex head tek screws (self drilling) were used, one every 2nd corrugation.

The completed roof made a world of difference inside the container. DRY and COOL. It was also up just in time for a very un-seasonal unusual heavy rain event in October over 300 mm in a week! (should've been the dry season but weather patterns seem to be getting more unreliable lately) The photo below also shows how green the lawn and trees suddenly became!

Shed extension #4

Just finished the NE shed roof extension #4. It is about 8 x 13 ft in area. The sturdy frame ran directly off the low workshop roof and 3 good sized corrugated sheets covered it. Tek screwed every 2nd corrugation to fasten.

Extension # 4 framework. 

The beam is recycled hardwood 5"x 2" about 14 ft long. The purlins are recycled and new galvanized steel top hat.

Framework from north roof

Cyclone Dylan was heading for us on the 30th Jan, so battened down the wyloyard and home in preparation for it. (Astronomical King tides of about 4 m were happening too, so any storm surge would have had a big effect if the timing was coincident) The port of Townsville was cleared with all big ships steaming out to sea before it reached land. However overnight Dylan changed course, intensified to Category 2 and veered southwards to cross near Bowen on a low tide. It hammered in from seaward and Hamilton Island in the WhitSundays experienced 120 km/hr winds plus some damage. At Airlie Beach a few yachts broke off their moorings, with one 28 footer becoming a total loss. As Townsville was were north of the eye, we were in the navigable semi-circle, and experienced only 25-40 knot winds coming from the SW and minimal rain..the wind had to cross hundreds of km of land mass to reach us so got weakened by that.


After the cyclone all clear, i returned to make a hinged shutter window on the wall below extension #4. It is simply a corrugated iron sheet set horizontally, with two hardwood beams 3 x 1" across at each end. Two pivots were made of 10 mm threaded rod going through 12 mm holes drilled through the upright poles. 60 cm rods hold it up at each end in the open position to let the breeze into the workshop area. A fern garden just outside helps the natural cooling effect, it felt like having about 2 fans going. It drops down quickly to control temperature, if the winds too strong, at night or in driving rain squalls. It is tek screwed onto the upright posts to hold it fast in cyclones.

Finished extension with ventilation shutter and irrigated fern garden

Ventilation shutter from inside shed's workshop area

I first came across horizontal shutters on Manihiki Atoll in the Cook Islands in the 1970s, Many houses there had wide eves, lower walls about 1 m high then horizontal shutters above these. (no glass windows at all) The shutters were made of 3" x 2" pine frames, galvanized nails and masonite, then painted. A bolt each side for the pivots which were placed about 1/3 down from the top to give some balance. Inexpensive but quite effective.

Shed extensions

In 2011-2012 the wyloyard underwent a re-build. The boatyard layout has been re-arranged and the roof and storage areas extended. 

In the 9 years i was away working in SE Asia, the wylo forest  had grown considerably in the dry-wet tropical environment. Also re-starting the boatyard after such a long shut down feels a bit like trying to re-start the  Panguna mine. (Put another way, its far easier to keep going once you start.)

After some planning time, the dry lockable storage extension was to be a 40ft (12m) sea container,  near the end of its serviceable life travelling the worlds oceans. The main shed would have lean-to veranda roofs and one 14ft caravan was to be turned to open up the work space.

One reason for the extensions is to do away with the sheds side-tarpaulins. Tarps on light-frames would be great in a temperate or equatorial latitudes but being in a cyclone belt, i made the tarps quickly removeable, hoisted like sails on two halyards each then guys ropes deployed to neaby trees to hold them out. Mines a long term-part-time build pattern, so had to hoist and lower the tarps every intermitent 2 week visit, to protect them from Sun and wind damage. This system made them last well but takes limited building time up. Once the iron roofs up, tarp worries are over.

Another good reason is to clear all the stuff stored under the hull and convert that from materials stock-piles to work areas.

Clearing and earthworks

Tree felling and clearing began around mid 2011, the worst tree was a fast growing introduced weed-tree called Leukina. Officially introduded as a miracle cattle fodder decades ago,  has broken free of the cattle farms and is now colonising native bushland. The Leukina had grown into about 12m high trees in 10years.! The oldest one had about 6 trunks and was 12m high monster with similar width of canopy. It reproduces prolifically and is very resistant to common herbicides, finally found one at  Elders agricultural that could dispatch the stumps and reshoots. Had a few bonfires ontop of stumps.

Used a Makita electric chainsaw. Made a toppling-direction error in the early days, one of the monsters trunks took its final revenge and toppled onto the wyloshed roof causing damage (later repaired). After that at least two stout ropes were attached high up any tree to be felled to ensure it would land safely in the intended direction, and miss sheds, vans, fences, powerlines etc.

Hired a Bobat and Brett did a good job of levelling old banana circles and creating a U-track for cars right around-through the boatyard. Also spread a few truckloads of "Deco" (decomposed granite) out on the main access driveway and i pruned a few trees so a semi-trailer could get in over the potentially boggy clay soil. He also had a stump grinding device which could attach to the bobcat and made short work of the remaining stumps (like leukina, fire resistant too).

Next stage Brett, also a concreter, made 4 footings pads, leveled, with cyclone-chains embedded for the seacontainer.

Sea-container

It took awhile but found and purchased an old  40ft long high-cube (9ft headroom) sea-container from the Townsville ports container yards.  Shortly after the semi-trailer rolled in with it.  The giant box was side-offloaded exactly onto the 4 square concrete footings with the trailers 2 lifting arms, chains and a handheld remote-control the driver operated. It has a few dings, dints and scrapes but is mostly a solid piece of  engineering.

Good access is important, preferably a straight drive in, mine wasn't and involved a 90 degree truck turn. I though i'd allowed plenty of room but turning circle was a bit tight, so a few logs allowed the semi to drive over a footing to get in..

Container on footings which keep it about 30cm above the ground. Chains are shackled onto each corner to prevent movement in a cyclone.

The dry cyclone-proof storage space was increased many times by this container, enough to handle boatbuilding stores and even household, furniture, vehicle storage  at a fraction of the cost of a permanent shed. The container can be moved or sold off in the future if required. It also doubles as a new far stronger southern wall to the yard (the original fence-wall was blown over in cyclone Yasi in Feb2011). Also theres about a 30cm high space underneath the container to store long pipes, old gutters etc neatly and fairly dry on the ground below it.

Boatshed lean-to extensions.

Saved  paperbark bush poles from the tree clearing work for the sheds upright poles. Paperbarks have high rot-termite resistance and are a strong hardwood. Stripped the bark off (better done green), treated the underground parts with econo termite deterent, augered and dug footing holes 90cm deep and planted the poles in handmixed bush-concrete.(Chain block lifted the heaviest poles, 10" diameter) The ute came in very handy for this, carting one load of well priced 700kg of concrete gravel-sand mix from the Bohle quarry to site, after off loading just add cement from bags and mix in a wheelbarrow. Its far less costly to make small batches of this concrete in a remote site like mine.

A small semi-protected storage alcove/ construction wall was created in the sheds SE corner with an extra ground post and horizontal corrugated iron sheets tek screwed on. It neatened the yards outer appearance, replacing an old shade cloth "wall". Things stay a bit drier and are out of view.

Next stage was to swivel one old 14ft Caravan around 90 degrees. The vintage wheels rolled out of the shed, pumped them up at the local petrol station and didn't even leak, the hubs rotated even after a decade in the elements. Mike helped with moving the van around, which really open up the workshops usable area. Then new cyclone tiedown footings (60cm) were dug, long steel rings embedded in bush-concrete and galvanised turn-buckles with shackles the final connections.

Main workshop area roof.

Framing. Decided to lower the 7m steel truss from its high 1999 position on the north end of the main boat shed. Mike was over and Chain block and come-along mechanical lefting devices help. 1/2"augered through the 12" end poles and bolted the truss into its new lower position. The trusses lower edge is just above wylo deck level, so there's just still room to work on the self-steering gear, and allow the davits to be extended above the workshop roof.

Next 3 long 6x2" or 5x2" beams were set up. The smaller in the middle as the 2nd hand truss had a nice upward bow in it. Augered and bolted together. Electric chainsawed the tops off the bush poles flush with the beams.

Purchased some 7m, 65mm tophat galv-steel roof purlins, from a company with most gigantic steel shed i've ever seen. Umungous gantry cranes loaded heavy Semis with 10 tonne steel beams and their square towering cabs, dwarfed  Jae the ute. Loading laws had gone heavier that i'd expected but just squeezed into the new regulations with  cut down purlins on the utes 2 ladder racks. Time to make up a front bumper-bar ladder rack (had one on the old XY Falcon wagon, to carry long loads) and perhaps try a smaller steel shed next time.

As the lightweight purlins went up realised the old bush-pole shed wasnt entirely square after all, so purlins adjusted accordingly and not noticeable. Bob, a mate down the road, gave me some old roofing iron he had lying out the back half buried in clay soil, jae needed a hose down and so did the sheets. They also needed some doctoring to straighten up. 16ft long, 4 have covered half the workshop area and old tool shed too, dramatically reducing scorching sun heat, rain and water.

The sheets are held down by 40mm tek screws from Boltmasters, Bohle. Got the wrong size at first (50mm) but they exchanged the box for 40mm, thankfully. It right for old style corrugated iron sheets.

Roofing work carried out early morning or late afternoons.



The workshop roof iron is going up. 7 m steel truss on right side. 

The workshop roof iron is up now  Its about 24 ft by 24 ft. It  was well worth the effort,  cool and dry at the workbench area,  the garden shed at left is also covered so doesn't heat up. The shed fence (at back) was also rebuilt to 6 ft high with new post and sheet iron.


Workshop roof from boat.

The western shed extension is now completed! Extra dry shady space. Its built in the same manner as the rest of the shed. Paperbark poles, recycled hardwood 6x2" beams bolted on, new 65 mm tophat purlins and recycled roof iron. Tek screw fasteners. The builders strap makes an X brace below the purlins, builders strap also holds down purlins on corners and edges edges.

Western roof - About 24 ft long and 13 ft wide. Wood-working workshop area (hatches, spars etc). It's also car access to the general workshop area.  The western afternoon sun was previously a  problem, heating the hull up. Now most of the hull is shaded in the tropical afternoons.

The sea-containers also been getting a bit of old fashioned rust chipping, rust-killer (phosphoric acid) and primer treament.



The SE alcove walls are 6ft high. A middle post went in to support the sheets. It keeps some materials semi-sheltered and away from hull.

 

SE Alcove with container southern wall behind.