Pete W's Tin Shed Project.

[DMIOM]

I had a phone call to say the Kingspan (seconds) will be delivered on Monday.

The guy also told me that I don't need to tape the cut edges.

and, of course, he'll gladly sell you some more after the winter if this lot gets spolied by the wet ... ?

[Pete W.]

Hi there, DMIOM,

Thank you for your reply - it took me aback!!!

In response, I've revisited the Kingspan site and see that the pitched roofing grade is not allowed to get wet.

I was a bit misled by discussions with a friend - he has just finished roofing a large workshop with roof panels comprising an inner steel skin and an outer profiled steel skin separated by a foam insulation layer.  These panels are made by Kingspan and he reckons that the foam in them is closed-cell.  His architect's designs just call for any exposed foam to be protected by flashing strips.

I shall store my sheets under cover and tape any cut surfaces.  It does mean that the joints in my timber framework will need to be kept from intruding into the corners of the spaces.

Thanks again for prompting me to check that aspect of things.            

[Pete W.]

Hi there, all,

I'm suffering a bit of morale-droop here these last couple of days!                   

The insulation has been delivered but is occupying ALL the spare space in the tin shed so I can't work in there.      

The steel roof sheets are on order and paid for but I haven't been given a delivery slot yet.           Or an order acknowledgement!!          

Dealing with three dead computers and also building a new gaming computer for my lovely but shy assistant has diverted me from getting out and foraging for the timber for the new roof frame.          

And the weather has turned wet so I can't yet start to strip off the old roofing felt!          

What I really want to do is work IN my workshop but I can't even work ON my workshop!                   

[awemawson]

Buy a cheap pop up gazebo off ebay for £30, shove all the materials under it and get on with the shed

[Pete W.]

Hi there, all,

I have now taken delivery of Kingspan insulation, box section plastic coated steel roof sheeting & fixings and 6-off, 4.8 metre lengths of 100 mm x 50 mm CLS.  I've also found some nice heavy-gauge polythene sheeting for the vapour barrier, in fact enough for a double layer.

The weather forecast for East Hampshire looks good and dry for the next few days so I plan to strip off the old roofing felt on the workshop quam celerime.  In preparation for that, I first need to prop the centre of the roof from the inside, just in case.
I've also got a couple of 12' x 8' tarpaulins in case the local cricket club ('white man's powerful rain-making magic'!) negate the weather forecast.          

[vtsteam]

Well if you get our weather after it crosses the pond, you're in for a lovely spell of summer like conditions -- we had it for nearly a week. It was a joy to be outside, and the fall colors are fantastic this year. So fingers crossed, your shed plans should go well! 

[RossJarvis]

Hiya Pete

I'd missed the latest progress, Sympathies re the lack of shed space hopefully you've managed to get somewhere with the recent gaps in the rain.  Remember, if you need a hand give us a bell or e-letter.  I can't promise to answer the phone or be able to come round, but it's worth a try at least.

Ross

[Pete W.]

Hi there, Ross,

Thank you for your post.  Thanks also for the offer of help, much appreciated.          

I currently have the trunks of six mature stinging nettles in the garden -  they're big ones, 4.8 metres of 100 x 50 mm CLS.  The timber yard doesn't seem to sell the hairy rough-sawn timber anymore!  They arrived on Friday afternoon and promptly got a coat of green pickle in case of rain.  The 'pickle' is called 'Duck's Back', I hope it lives up to its name.  I've been tinkering with the shed roof in preparation for my gallivanting about up there!  One task was to insert a 10' length of Dexion slotted angle (the big one, about 2½" x 1½") to relieve the load across the top of the two big front windows.   That meant removing the screws that fixed the front edge of the roof to the front wall!  The Dexion stops those screws going back in their original places so the replacement attachment will use some angle brackets.

Another task was making and fitting a couple of tapered blocks to the underside of two of the rafters to take a prop.  I set out to measure the slope of the rafters using the protractor from my Moore & Wright engineer's square kit - that failed because the spirit-level bubble was so close to the roof I couldn't see it!          

The prop will consist of a horizontal length of 3" x 3" supported by a 4" x 4" x 6' gate-post one end and a length of 100 mm x 50 mm that I've just brought back from the timber yard.  It'll be fine-tuned with some handy plastic wedges.  Once all that is in place, I can start to remove the old roofing felt.

I keep under-estimating the time these sub-tasks will take!           When there's a bit more progress to report, I'll try to take some photos.

[RossJarvis]

I keep under-estimating the time these sub-tasks will take!           When there's a bit more progress to report, I'll try to take some photos.

Re-jigging my Dad's advice on spending money, carefully think about all the things that need doing, add on 1/3 for mistakes and come up with a time, round this up to the next largest time span.  Then double this.  You will still take longer to get the job in.  I also tend to double this again to take in tea breaks etc. (it still takes longer) .  It might be better squaring or cubing the second estimate.

[Pete W.]

Hi there, all,

At last, I have some progress to report!          

I started by fitting the length of Dexion slotted angle to give added support to the front of the roof over the two front windows. 
After I removed the screws securing the roof, I tried to lift the roof but failed completely!!          

Then, out of the blue, we had a visit from my #1 step-son and his girlfriend.  'Did you have your spinach this morning, Bob?' says I.  'Why?' says Bob.  Well, he took one look at the situation, rolled up his sleeves and heaved.  It was almost a 'You're only supposed to blow the b****y doors off!' moment, I thought he was going to put the roof into orbit!  Anyway, here's the result:



That piece of Dexion only extends a couple of inches beyond each end of the windows but at 10' long it's the longest length they stock.  The Dexion blocks the holes where the original screws went so I fitted some angle brackets to re-attach the roof to the front wall.  The sharp-eyed among you may notice that I used countersunk screws - I intended to use round-heads but their 'pro-drive' sockets didn't fit my Pozidrive screwdriver!

The next stage was to fit a temporary prop to the underside of the roof to give added support for my 15½ stone while I was gallivanting about on top!  I made and fitted a couple of tapered packing pieces so that the prop had a level surface to bed against.  The prop has three parts, a length of 3" x 3" timber, a 6' long 4" x 4" gate-post and a 6' length of 4" x 2".  The pillar of the drilling machine was in the right place to play a part in the rigging and operation.  My lovely but shy assistant called it 'a Heath-Robinson affair'!  Here's a photo:



After all that, it was a case of get up the ladder and strip off the felt.  That's taken a couple of days with a shed-free day in between (my 76-year old knees can only take so much!).  As of this afternoon, the felt is all off.  My lovely but shy assistant has done a superb job tearing all the felt into small pieces ready to go to the tip.  Here's what it looked like when we'd done:



And here's a close-up of one corner:



Not exactly prime quality timber but it's not in bad condition considering I bought the shed in 1993.  Of course, the shed is now vulnerable to the weather so it was 'Pipe all hands aloft to set the main-sail'! (i.e. fit a couple of 12' x 8' tarpaulins.)  Just like an instalment from the Hornblower series.  From inside the shed I can see lines of blue light through the gaps in the roof boards.

Very pleased to have completed this part of the job             but the weather looks as though it'll be a couple of days before we can do the next part which is fitting the vapour barrier.  (As Ross said in his post, the Hampshire Monsoon is upon us!) 

[vtsteam]

Here's hoping the tarps do their job!

And a good supply of buckets and pots and and cans if they don't -- as mine don't whenever I try to do something like that. Water pools in the cracks and spaces, bulges for awhile, and then.......ploink, ploink, ploink! 

[Pete W.]

Here's hoping the tarps do their job!

And a good supply of buckets and pots and and cans if they don't -- as mine don't whenever I try to do something like that. Water pools in the cracks and spaces, bulges for awhile, and then.......ploink, ploink, ploink! 

Hi there, Steve,

                 

I regret to report that the tarps didn't!

I carefully covered the bare boards of the roof before leaving the job last evening, roping the tarpaulins' eyelets down to large screw eyes .  It started to rain here later on.  We went to visit a family member this morning and soon as we got home I went to check the shed.  The tarps didn't seem to have kept any water out at all - everything is dripping wet!  The contents of any upward facing vessels with a waterproof bottom (e.g. tote boxes) are probably swimming now!

As a temporary measure, I've spread out the heavy gauge polythene I intend to use as the vapour barrier on top of the tarpaulins and weighted it down with about about three dozen house bricks.  It was too late to attempt a rescue operation this afternoon.  A friend of ours lent us a dehumidifier a few months ago when our motor car was suffering rainwater ingress - I'll ask him if he can lend it to us again.  That's once I've established that it's safe to switch on the electricity.  Otherwise it'll be a mop and bucket job.                   

I suppose I could always ask my lovely but shy assistant if I can bring the lathe and drilling machine into the living room for a few days.         

[awemawson]

Pete, very sorry to hear that, anything I can do obviously ask. I do have a largish commercial de-humidifier you'd be welcome to borrow, but iirc you're the other end of the A272 so possibly a bit far to travel.

Do you have any places locally selling pelletised sawdust? I use it for spillages and it's excellent drawing the moisture out (The wife buys it by the half ton in 10kG bags for Goose bedding)

Lots of ventilation

[Pete W.]

Hi there, Andrew,

Thank you for your post, your sympathy and for your kind offer.  However, as you say, we're further apart than I have the time to travel - I'd rather spend the time mopping up.  As I said, we might be able to borrow a dehumidifier closer to home.

A good hint about the saw-dust, though.  We have yet another friend who makes kitchens and generates lots of sawdust; the only think is that his sawdust is predominately from MDF.  Do you think that would be sufficiently absorbent?  Or does it have to be pelletised? 

[awemawson]

Pelletised stuff is just easier to handle. I wouldn't hesitate, just dowse things in sawdust then sweep it up or clean it up with a wet'n dry workshop hoover. Put delicate stuff like verniers and dial guages in a poly bag with some rice from the kitchen - that sucks moisture out very well as well.

I've been known to pour cement powder on the floor in a crisis, but that was when a bottle of Hydrochloric Acid got spilled  and the (alkaline ) cement not only absorbed the HCl but neutralised it as well. Loads of fizzing of course 



  (Oh yes, life gets exciting round here sometimes) 

[Pete W.]

Hi there, all,

Andrew, I hope that you are well and/but not over-doing things.  Thank you for your recent offer of help following my leaky tarpaulin problem.

I collected the dehumidifier from our friends on Monday morning and set it to work.  By that time the water had ceased to drip from the underside of the roof.  There was some free water on the vinyl floor covering but otherwise far less elsewhere than I'd expected 'après le déluge' of Sunday evening!  Maybe there is some water lurking out of sight!

The dehumidifier collected about two litres on Monday.  I moved some tote boxes of stuff indoors and was pleased to find no water in them.  The PVC cover seems to have kept any water from getting into the lathe swarf tray.

I didn't operate the dehumidifier on Tuesday because I'd removed the polythene and tarpaulins to let the sun get to the upper surface of the roof boards.   I had previously thought that the roof boards were T&G but they're just plain rough-sawn, far from uniform thickness and some waney.  After a couple of hours, I swept the remaining mineral granules (shed from the roofing felt while it was being stripped-off) off the roof and gave its upper surface a good coat of wood preservative.  I tried to leave that as much time to dry as possible before replacing the polythene with the tarpaulins on top and roped-down to keep all in place.  It's wet today so the covering will be left in-place with the dehumidifier running again.

The next stage will be to fix the polythene vapour barrier in place properly and then to make the timber frame - the weather forecast for tomorrow is mostly dry so hopefully I'll be able to make a start with those tasks.

[awemawson]

Pete, Glad it's going back together, and thanks for the thoughts. Hopefully I'm doing enough to keep my sanity but not too much!

When  the vapour barrier is up at least you can rest easy that it'll be starting to dry out, but it's amazing how much moisture a building can contain in it's structure. Controlled ventilation is the key - make sure that you choose the drier days for the open doors and windows!

Dehumidifiers will only work when there is a bit of warmth about - the moisture has to be in the air to be condensed by the machine. Also the shed needs to be pretty well airtight when it's running. When we were desperately drying out our kitchen extension last winter I had mine, and a hired, dehumidifier running 24/7 but to get them going had to put a 4kW electric air heater in for a few hours to warm the air. Once it started working the heat of the driers was enough to keep the temperature up as they each consumed something like 3 kW when running.

Reading the electricity bill was enough to keep us warm !

Good luck,

Andrew

[RossJarvis]

We had a dehumidifier in our bathroom.  The beloved thought it a good idea to always leave the window open when I wasn't looking .  Explaining how difficult it is to dehumidify Hampshire and West Sussex didn't go down too well!

[vtsteam]

Glad you got it under control Pete, and your things spared. Wishing you good weather until you've got your roof on. 

[Pete W.]

Hi there, all,

I've continued to work on this project, as weather has permitted.

One task has been to convert this:



to this:



I know that's a crude drawing - I tried to produce it in Autosketch but failed utterly!!          

     Does anyone know whether you can enter the coordinates of a rectangle (diagonally opposite corners) from the keyboard in Autosketch 9?

I've got the six-off 4.8 metre lengths cut into the correct length pieces for the frame (not very photogenic so no picture of them!) but they're not assembled yet (see below).

Another task has been to trim the rough edges off the three 2.4 metre by 1.2 metre sheets of Kingspan and to tape the edges.  My lovely but shy assistant helped me do the first sheet and then Ross came over today and helped me with the other two - thank you, Ross.                

I was torn between assembling the frame in-situ on top of the old shed roof and assembling it at ground level (well, on trestles).  The former would have been awkward while the latter would have required us to lift the whole thing into position, quite heavy and tricky to steer past several overhanging tree branches!  Then I realised that if I make four of the joints capable of being disconnected we could lift the frame in two parts and re-assemble just those joints and the centre row of noggins in situ.

That required another shopping trip to buy some fancy wood-screws that provide good grip in end-grain.  Because the joints are close to the ends of the timbers, I intend to drill pilot holes for both the wood-screws and the fancy outdoor treated nails so I also had to buy some long series twist drills.  Actually, the joints only have to withstand the loads of handling - once the steel roof-sheets and flashings are on, their fixings will hold the frame together. 
 

[awemawson]

Glad it's all coming back together Pete. Watch the lifting - don't want anything popping out that shouldn't 

[vtsteam]

Pete, good idea about the section assembly! Working alone or shorthanded gets you to be creative with your thinking! Sure beats struggling to do something that is nearly impossible or dangerous.

I like your idea! 

[Pete W.]

Hi there, all,

I've managed to grab most of the dry days to get some more work done on the roof frame for the big shed.  I cut up the six 4.8 metre lengths of 100 x 50 CLS timber into the lengths determined by my drawing (supported by some VERY careful measurements of the existing roof).  Much to my pleasant surprise, the lengths of the roof at both the high and low edges were equal to within a millimetre as were the widths at both ends and both the diagonal measurements!           

After giving all the cut ends a coat of 'Duck's Back', I marked them out with my Sabatier marking knife.  It then rained for several days and although I covered the pieces as well as I could, I feared the wood might swell and erase the markings.  [My lovely but shy assistant often tells me 'not to make the negative waves'           ]  (That was a film quote!)

Not having a workbench 12' 6" by 8' 6", I had to improvise a bit, not helped by the uneven terrain of our back garden!  I then started the assembly.  The four outer corner joints were a bit tricky and needed a bit of help from my lovely but shy assistant.  Once those were secure, I could fix the remainder single-handed.

Here are a few photos:

The first two show how I clamped-up each joint, holding the pieces together in-position while I drilled pilot holes and drove the screws.  (The off-cut of timber held by the two largest cramps is the one that permits single-handed assembly.)





This next one shows the situation at close of play this afternoon.



The diagonally opposite corner joints nearest to and furthest from the camera and the adjacent joints between the inner purlins and the end pieces are each secured with two wood-screws; they are the joints that will be demounted to divide the frame into two sections to facilitate lifting onto the shed roof.  All the other joints in the photo are secured with two wood-screws plus a large nail.  The middle row of noggins will also be demountable for lifting.

The noggin intended for the position nearest the camera proved to be a whisker too long.  I didn't want to drive it into position for fear of straining the corner joint.          

I have a further 2.4 metre length of timber so I shall cut an extra noggin to fit that position.  I also need a tenth noggin because I've modified the plan from the drawing in my last posting.  I spent some of the rainy days scheming out various ways of cutting the Kingspan insulation and the best scheme I've found requires several noggins to be repositioned and an extra one added.  When I've completed the ground-level trial assembly, I'll take another photo to show the frame in its revised form.

As there will be several pieces cvompletely removed from the frame for the lifting process, I'll need to choose a system of marks so that each piece goes back into the right place!  The marks will be made with a Sharpie pen - not incised with a chisel like the green oak framers' method!            

In the background of the third photo, you can see the box section steel sheets awaiting their turn in the project!

[Pete W.]

Hi there, all,

Well, I've managed to make a bit more progress, here's a photo:



It's a frame, it's green, but it isn't OAK!  Still, 2 out of 3 can't be too bad!          

As you can see, I've now fitted all the noggins.  I've even managed to annotate the photo - all the joints marked with a D will be demounted to separate the frame into two major sections for easier lifting onto the shed roof.  Just re-making those joints in-situ will be easier on the knees than if I had tried to assemble the entire frame up there!  Nevertheless, I've bought myself a fancy pair of memory foam knee pads!

But before I do any of that, I shall lay an 8' x 4' sheet of shuttering ply on top of the frame to make a level surface to support the Kingspan insulation while I cut the pieces to size to fit the various frame openings.  Having chocked-up the frame to be out of winding, it's the most level surface in the place!  When I've finished cutting the Kingspan, and the ply is removed, I'll fix a few temporary braces to the frame before demounting the D joints.

Another minor task that I need to do before the 'Big Lift' is to finish stapling down the edges of the polythene sheet and vapour barrier and to trim off the surplus all round.

For the 'Big Lift', I shall mobilise any available heavy gang but the basic plan is to position two 10' sections of aluminium ladder with their lower ends on the flower bed and their upper ends just over the top of the shed roof and slide the frame sections up them.  That part of flower bed is significantly higher than the floor level of the shed so the ladder sections should be at a manageable slope.

Because the overall length of the frame is determined by the pattern geometry of the box-section steel sheets, the frame is actually slightly longer than the existing shed roof.  I still have to decide whether I want the overhang at the door end, the other end, or a bit at each end.            

[awemawson]

Looking good Pete 

I'd suggest overhang by the door - a bit of shelter is always useful. I have strategically placed golfing umbrellas at the doors of my various outside workplaces as I hate donning coats 'just to nip over to the workshop' - and room to raise & lower them when it's raining is very useful 

Andrew