I wanted to make a custom wooden storage shed, with plenty of room for both tools/DIY equipment, and also family stuff like toys, bikes, etc. The shed was to be located at the front/side of my house, also acting as the fence between my driveway and a side courtyard.

My requirements:

1. Aesthetics - Because it is at the front of the house rather than hidden at the bottom of the garden, it needed to look as smart as possible.

2. Size and shape - Because of the space it is filling it needed to be a custom size and shape, hence my need to design and build it from scratch (rather than buying a shed kit).

3. Structure - Most shed kits are just single layer, and very thin cheap wood. I wanted this to be secure and sturdy, both for security reasons, and to allow it to stand the test of time.

(This is my first Instructable).

Supplies

Base - Concrete blocks, cement, sharp sand.

Framing - 3x2 and 4x2 treated timber (I used C24).

Walls/floors/roof - OSB3 (18mm for floor and roof, 11mm for walls).

Housewrap/breather membrane - this will make the walls weatherproof but breathable.

Cladding (and trim boards) - I went with Siberian Larch 22mm cladding, which is available in a range of profiles and sizes.

Battens - I used standard roofing battens which are cheap.

Roof - EPDM rubber, deck adhesive, contact adhesive.

DPC.

....And thousands of screws (decking screws, stainless steel screws, cladding screws, range of sizes from 50mm to 150mm).

Step 1: Planning

I didn't have access to any professional software to help me draw technical drawings, so I did a lot of sketching on squared paper to work out dimensions and materials. You can do this however you like, but a few pointers:

1. If you've got time, don't be afraid to research around to find the best prices for materials. I was amazed at how something as simple as a length of wood varied in cost. I live in SE England, and I estimate I saved going on for a few hundred quid just by finding the cheapest suppliers around. Also, eBay is a good place to find a lot of things (I bought my EPDM roof as an offcut at a fraction of the price on eBay).

2. Don't forget delivery charges, which can mount up (unless you have a van).

3. It seems stupid, but always get at least 10% extra of everything, especially anything you have to pay delivery fees on.

4. You will avoid a lot of sawing if you design your building to multiples of standard wood sizes (for example a sheet of OSB is 8x4 feet, if you make the shed 8 feet wide then you will simply have to lay two pieces next to each other for the floor rather than cutting).

Step 2: Base

There are numerous options for building a base, and the best one will depend on your individual situation. The most important thing is to make it strong, level, and impervious to moisture creeping up. Ideally with some airflow underneath.

In my case, I was building on sloping concrete, so decided to build a series of piers to level off the base.

1. Mark out your base with spray paint.

2. I laid strips of fine mesh first, which fold up to prevent rodents from nesting underneath.

3. I used concrete blocks (broken in half for economy). Lay them on mortar, and add bits of brick, paving slabs etc to the top to level it out.

4. Build the floor joists out of 4x2, to the size of the footprint of the finished shed.

5. Lay the joists onto the piers (put some DPC underneath to protect the wood, and use some more mortar mix to finally level it in all directions (much easier with a helper).

6. Another layer of DPC, and a layer of breather membrane (not necessary but I had more than enough so why not), and then lay sheets of 18mm OSB3 down for the floor.

7. Fold up the mesh and tack it to the joists.

There is your finished base.

Step 3: Framing

At this point you need to build your wall and roof framing. I used 3x2 timber for the walls, and 4x2 for the rafters.

1. You will want to do some more sketching to make sure you incorporate any doors or windows.

2. A chop saw is ideal for cutting the wood to size if you have one. A circular saw will do if not. Obviously a handsaw will also do the job.

3. I used 16 inch centres for the studs (the distance between each upright piece of wood).

4. Building these is straightforward enough - a long piece of 3x2 at the bottom and top (top and bottom plates), and pieces cut to the height of your wall screwed into each (the studs). Use a speed square to make sure each stud is square to the plates.

5. Dependent on your desired roof profile, you will need to make sure one side is higher than the other. I used a simple angle calculator online to work out the height required to give me a roughly 10% roof pitch.

6. Lift these onto your base and screw the floor plates down.

7. I was attaching my shed to a brick wall on one end, so at this stage added the end wall, and screwed the end studs into the brick wall.

8. Add a second long piece of 3x2 to the top on all sides - this will help to stabilise the whole structure and hold it all together.

9. Then, cut roof rafters from 4x2, using the angle calculator again to cut a slight angle on each side (so they are upright at the ends). I cut a slight birdmouth joint into the ends to enable the rafters to sit flush (see picture). Screw the rafters into the top plates from above to bridge the two walls.

Step 4: Sheathing

Now you're ready to add the walls and roof.

1. Cover all studs with the thinner OSB3 (I used 11mm) and screw them in. This is easier with a person to help as they are heavy and awkward.

2. I ran the OSB all the way to the top (covering the ends of the rafters), to create a seamless box, then added to overhang part later (step 5).

3. Lay the thicker OSB3 (18mm) across the roof rafter, and again screw them down.

4. Now cover the all walls with the housewrap or breather membrane. This is an important layer, as it will keep any moisture out but still enable the structure to breath to help stop condensation. You can buy expensive tape for the joins - I just used duct tape.

5. I screwed some small scraps of 4x2 to where the roof rafters ended, and put a thin strip of OSB3 on top to create an overhang on each side.

6. I also added some small vents to help stop condensation later on. To fit these you just drill a hole and push them in.

Step 5: Roofing

Now its time to cover the roof. I didn't take any pictures of this step.

There are a variety of materials you can use, but the main choices are felt or rubber. Felt is cheap but has a much shorter life expectancy. EPDM (rubber) is more expensive but lasts a lot longer. I went with EPDM, and got a good deal on a long section of offcut on eBay. You then just need some glue (you can buy specific glue for this job) and some contact adhesive.

You can buy special edging profiles, but I just let the edges overhang as I was going to cover them up with some timber trim.

1. Lay the EPDM on the roof for a few hours - this will 'relax' the sheet and help stop wrinkles.

2. Peel back one half. Using a standard paint roller, roller glue on the entire roof apart from a 15cm perimeter around the edges.

3. Lay the EPDM back down, and with a broom, brush it flat. This will stretch out all creases and wrinkles. Repeat this step for the other side.

4. Let the glue dry for an hour or so, then, when you can, fold up the edges and paint on the contact adhesive (different from the glue as it is an instant bond).

5. Important - let the contact adhesive dry until it is touch dry before you stick down the edges. If you don't do this then as it dries it will create bubbles in your rubber due to the fumes it creates.

6. Once contact adhesive is touch dry, stick down the edges.

Step 6: Doors

I constructed the doors in exactly the same format as the rest of the shed.

1. Trim the 3x2 to size, building a big rectangle the size and shape of your door.

2. Add the cross piece in the middle.

3. Measure carefully, cut carefully, and add the diagonals. They should both fall from the outer edge, down towards the hinge side, as shown in the picture.

4. Sheath with OSB3, and cover with breather membrane.

5. This door will be heavy when clad. To mitigate against any sagging, I added a spring loaded caster/jockey wheel, which will sit on the shed floor when closed and help support the weight of the door.

6. I used 150mm stainless steel parliament hinges. These are designed in such a way to protrude from the surface of the door, which will enable them to clear the cladding. To make sure this would all line up and and open and close once the cladding was fitted, a built a quick dummy model out of a couple of pieces of scrap to simulate the hinge mechanism - this was 10 mins well spent.

7. I attached my lock at this stage. I used a keyed garage door type lock (mainly because I didn't want an ugly great padlock on the front).

8. Screwing the doors to the door frame, alone, was very hard. Get someone to help you. I rigged up an aide with a couple of car jacks and wish I had just called a friend.

Step 7: Cladding

Now time for the cladding. If you are like me and consider the aesthetics to be very important, you'll have carefully selected your choice of cladding based on what you want the final look to be. I used planed 22mm Siberian Larch which looks lovely, and is very strong and stable. I went with a 'Shadow Gap' profile, which I think gives a very clean and contemporary look.

Your cladding provider will be able to tell you what screws you should use and how many per board. I used stainless steel tongue and groove/floorboard/cladding screws, which have a very small head and are almost invisible once fitted.

Fitting it isn't that difficult, as long as you are careful measuring around the doors.

1. First, you will need to install battens around the shed, drilling them into the studs. You could probably get away with screwing battens onto every other stud, but they are so cheap I did every one. These are what you will drill your cladding onto, which will leave an air gap behind. Don't be tempted to fit the cladding directly to the shed.

2. Start at the bottom, leaving a gap to the floor for air and moisture. Screw one side with one screw, then you can manoeuvre the other end up and down with a spirit level until it is level.

3. Once you've got the first one on, simply work your way up, checking with a spirit level every now and again, screwing into each batten.

4. For the corners, I made an edge trim by cutting a couple of long lengths of cladding strips as pictured. You can just buy this trim. I glued and screwed it in place.

5. To cover the roof overhang/eaves, I had also bought some Siberian larch boards, which I installed with the help of a roller balanced on a stepladder - get someone to help you.

6. I installed the trim boards at the top higher than the roof level to create an internal lip, as next I will be installing a green sedum roof on the shed - I'll do a separate Instructable on this one.

Step 8: The Finished Article

You can kit out the inside as you want. I had divided mine into two compartments, and over time will add as much innovative storage as I can.

I will also give it a fine sand (there are still some pencil marks etc) and apply a clear stain, which will delay the natural greying of the wood.

Overall I am very happy with how it turned out. I did tons of research in the design and build of this, and learnt a lot of new skills. Also it gave me an excuse to buy lots of new tools!

Hopefully this Instructable helps others in building their versions. I'll enter this into the 'Wood' contest.