How to Build a Shed or Workshop

I needed a new shed/workshop as my old shed was tiny, leaky and generally rubbish. I was going to buy a bigger shed when my brother (a retired builder) said we could do enormously better for the same budget (around £1000 not incl the concrete base or electrics). So we did.

Here's how...

Step 1: Materials

Obviously it all depends on the size (duh) you are going for, but this is what I needed for a 12' by 9 ' which is 7'2 high.

Studwork 3 x 2 192 metres total

'Sawn carcassing' 145mm x 45mm as vertical roof supports x 6

'Sawn carcassing' 70mm x 70mm as beams to support roof x 4

OSB boards for inside walls 2440 x 1220 x 11 x 9

Shiplap 19mm x 150mm 200 metres

Breathable membrane (I bought a 50 metre roll of 1.5m and had plenty left

Insulation for walls

Box profile steel sheets for roof

French door (eBay)

Double glazed window (eBay)

Lots and lots of appropriate sized screws

Step 2: Location, Location, Uh... Location

The only real location I could go with was the location of the current monstrosity. There was not enough room the other side of the tree and for some reason my wife didn't want me to chop the tree down. Grrr.

Step 3: It's All About That Base...

How to do a shed base is outside this instructable. There are lots of ways and it all depends on taste, budget and what your shed is for. I do blacksmithing, so I need a serious base than can take an anvil etc etc. I just got someone to lay down an overly thick (8 inches) concrete base.

Step 4: The First Cut Is the Deepest..

You know how high you want it, you know how big your base is, build the first wall.

In my case, the back wall has no windows so was the best place to start.

Cut 5 pieces of studwork to the length of your base (9ft for me). Screw 3 pieces together (this will be the 'bottom'), then other 2 together (this will be the 'top').

Add the thickness of these (10 inches for me) and subtract these from the height you want your wall. This is how long your verticals need to be. Cut enough pieces of studwork to be spaced every 40cm (see picture as example)

Step 5: Get Screwing

Imagine you are making a huge picture frame. The size of the wall.

Look at the back wall in this picture so you are familiar with how it will look.

Lay the 'bottom', the 'top' and 2 of the sides down so that it looks right. Now screw these together with nice long screws, 2 at each corner going right through. Make sure it's secure.

Now make sure it is all square and correct. Use builder's squares if you have them. If not, or also, measure corner to corner and adjust it until both of these measurements are correct.

Now add the rest of the studwork at 40cm intervals, checking the square as you go.

Now make the 'noggins' from more stud timber. These are the cross pieces. Cut to size then screw in. You can make these offset to make the screwing easier. But not if you are being supervised by your builder/carpenter brother. In that case you screw in one end as normal then the end you can't reach you screw in diagonally.

Congratulations, you have the skeleton of your first wall

Step 6: Membrane

Stable or nail membrane to the wall. This will help keep out the damp.

Step 7: Shiplap

It makes sense to ensure you start this job in a sensible direction, taking account of the way you will lift it into place. It will be heavy once shiplapped.

Cut the shiplap to the same length as the wall.

You will be shiplapping the side with the membrane on.

Mark where the studs are on the membrane so that you can easily find the position to screw into. A chalkline is best for this.

Start at the 'bottom', making sure everything is level and square.

Screw the first piece in in using 2 screws at each piece of studwork. Then repeat, making sure the shiplap is lined up correctly.

Keep going until you have a wall.

Step 8: Next Wall

The side wall will be the same, except for one important difference; the shiplap needs to go further than the frame in order to cover the frame from the previous wall (as well as the next wall).

To do this, screw another piece of stud to both side pieces. This is a temporary guide only. Make it a bit longer so it protrudes both ends. It will become apparent why.

Cut the shiplap long enough to cover the temporary pieces. I found it easier to cut it an inch too long then correct later, but if you are super accurate you don't need to.

Now shiplap as before, making sure one side is perfectly level with the temporary piece. If the other side overhangs it slightly you can cut it flush (making a chalk line first to help you see where you are cutting).

Now we are getting somewhere...

Step 9: Well How Does That Look?

You can put the 2 walls in place screwing pieces of timbers as supports. Use plenty of these in case a mighty wind comes....

This picture includes wall 3, but gives you an idea of supports.

Admire your handiwork.

Call your wife to admire your handiwork.

Step 10: Same But Different...

The front wall is the same as the back wall (no extra widths of shiplap or temporary pieces). But make a frame for the size window you have. Try to get it more our less level and square, but you can address this slightly later. Put this wall up and screw it to the other walls and use temporary supports so that you can get a feel for window placement.

After this photo was taken I increased the number of vertical supports under the window as it is h-e-a-v-y.

Step 11: Framed

With all the glass units out, screw the frame in place using packers if necessary to make sure that it is level, plumb and square. It is more important the frame is square that the timbers.

As my second hand window is excessively massive I had to use a separate timber on top rather than incorporate it in the wall frame otherwise I would have had the window too low for a workbench. To avoid this you can try not being as cheap as me and buy a window based on suitability rather than price...

Do not membrane or shiplap yet.

Step 12: Same But Different Pt 2

Do the same again for the door frame. The door frame screws directly into the base. The easiest way to achieve this is to make the cut later. We will come back to this.

For now, screw the door frame to the sides, screw all the sides together in place. Do not membrane or shiplap yet.

Stand back, admire your handiwork.

Call your wife out to admire your handiwork.

Step 13: Stick That Sucka Down

Here's what I did. There are other ways. Maybe better ways, but here's how I did it:

First of all securely screw the sides to each other. Then screw extra temporary pieces in each corner to make sure it is utterly solid.

I got a bottle jack and solidly screwed some pieces of stud to each side a couple of inches higher than the jack. These are 'jack points'.

Then I jacked up the sides one at a time just an inch or so and propped up each side with a couple of small pieces.

When it was all jacked up I squirted a few tubes of quality sealant under the bottom pieces then went round jacking, removing supports, and squirting sealant until it was all covered and lowered. The sealant is more for bugs and water than sticking down. It oozed out nicely when the shed was lowered, so I knew everwhere was sound.

Then I put a couple of anchor bolts through the frame into the concrete.

That shed ain't going nowhere..

Step 14: Making the Cut

You can now remove the door frame, cut out the bottom piece and replace the frame, bolting it to the base.

I did it in a slightly different order. I don't know why...

Now you can membrane and shiplap the front and side. Make sure the side shiplaps will cover the front and back as you did before.

Also make sure you overlap the window and door frames a bit to give protection. I did about 1cm.

I had a spare large sheet of glass, so I made an old fashioned window next to the door.

Call your wife to come and admire it. By now she may not want to come.

Step 15: Roofless People

Now we need to figure out how to get a roof on.

Figure out how much drop you want/need. You can use accurate measuring, if you have this skill, to cut the supports the correct height. I do not and that is why you can see extra pieces of timber on top of the supports to make up the height.

Do not show your wife that bit.

Step 16: Roof

Cut your roofing sheets to length and screw them to the supports using the correct screws and and method recommended by your supplier.

On the neighbour's side I used a 'barge board' that screws directly into the side wall and covers the roof ridge. I added some sealant for super double safety and because I always do.

On my side I have extended 6 inches. Unfortunately I took no photos of this stage, but here's how we did it:

1) We made something that looked just like a ladder 6 inches wide using stud timber. We screwed it firmly to the side to support the overhanging roof.

2) We used pieces of shiplap as fascia and soffit.

3) We screwed the soffit to the 'ladder'.

4) We screwed the fascia to the ladder and to a piece of batten we put on the roof (using extra sealant as always).

I hope this makes sense. I'll try to add a better description later.

At the front of the roof we used shiplap as fascia and screwed it to the wall and to a batten on the roof.

I did a slightly messy job on the corner of the fascia's as I cut the front ones too short. I'll be replacing this soon.

Step 17: Insulation

Run your choice of insulation in your studwork. This insulation came precut for 40cm stud spacing, making life easy.

It's just push to fit, but I stapled some string across to help keep it in place when the walls go up.

Step 18: Wall It Up

Cut your OSB board to size and screw into studs.

If the boards meet where they are not close to a stud, screw a batten to the first piece (see picture) and screw the next piece to it. This will pull the two flat and solid.

Nearly forgot, measure up and mark the batten and stud positions before you put the OSB in place.

Step 19: Let's See About That

Now we're getting there you can pop your glazed units in the window frame and hang your doors.

Seal around everything that needs sealing around.

Step 20: I Have the POWER

Get some electric.

Get some storage.

Get making things.

Step 21: That Darned Cat...

It appears Beezer the troublesome cat did not stay away from the concrete base like I told him to...