Frustrated by the lack of floor space in my new flat, I resolved to build the ultimate loft bed! I have tall ceilings at 2.75 metres, so building up seemed like the way forward...

Total material cost for this project, including hardware, bed base sabotaged from an old iron bedstead, and mattress from the same old bed was only about 175 quids, with about 110 quid on the wood itself.

All in all it took 2 days to build. I done the cutting and part assemblys myself on the first day, and on the second I had a friend help with the major assembly.

This bed is sturdy, thats for sure! Being an Engineer/Architect for a living makes you acutely aware of structures and strength, and I was paranoid that my girlfriend and I might plummet to our doom so I over engineered the thing somewhat... it is reasuringly solid though, and it is also wedged and packed off of the walls, thus it dosent move in the slightest, and no creaking either!

Step 1: Design

I enjoy designing stuff. Sometimes I end up spending far too much time designing and not just doing it though, but with this one I wanted to be sure. Concept design was done in Rhino 3D and hand calcs (beam theory) done in Excel. If I was being ultra geeky I may have done some FEA on it, but thats for another day! Suffice to say the hand calcs give me a factor of 3 safety with 2 people on the bed which is good enough for me.

The main load bearing side beams are therefore 200mm x 25mm and span 2.75m, with a 50mm x 50mm rail glued and through bolted along the bottom edge for the bed base to sit on. The main uprights are 100mm x 100mm. I could have got away with 75mm x 75mm here, but opted for the chunkier material instead. Under bed clearance is 1.8m, and me being 1.85m tall I can generally get under it if I slouch a bit! My girlfriend is shorter at 1.65m and has loads of headroom. Clearance above the mattress was 700mm. I deemed this to be the best compromise between useable space beneath the bed and sleeping room above it. I would say 700mm is at the lower end of the comfortable above bed clearance for sleeping.

I wanted the bed to span a whole wall so that the legs would not intrude into the room. This requirement drove up the need for beefier structure as it spans more than a normal bed. It was also necessary for my nice big desk from Ikea to sit under the far end, as this would be the only available space for it - I was still storing it in my bathroom!!! What is also cool about having it next to my little hallway is that I will be able to put a 24" cheapo Ebay CRT telly up at the far end of the bed for bed time viewing.

So, with these requirements, I started drawing in Rhino. As the design evolved the calcs were influenced and I kept to the factor of 3 safety with 2 people rule as closely as possible. the final design looked like this... I'm pleased to say that this is almost exactly what was built.

Step 2: Find Materials and Equipment

I was a little sceptical about being able to find pine in the dimensions that I had specified, but I was plesantly surprised on my visit to the local timber merchants to find hundreds of options! This did excite me. The guy there that managed the timber was also having a slack day, so between us we managed to pick out the best looking stock at the right lengths to minimise wasteage. He did a very good job of this, as at the end of the project I had a total of about 1m total length of wasteage!!! Also, I had several really good looking boards in terms of cleanliness and grain structure. They were also able to sell me the hardware required:

24x M10 130mm Coach bolts
12x M8 75mm Coach bolts
Large penny washers for the above
Gripfill building adhesive

I also took the oppertunity to buy a new saw, just a standard saw, but with slightly finer teeth for a more finished cut. M10 and M8 new drill bitts also minimised the effort required from my puny battery drill! This and a few measuring tools and sandpaper were all that was required to begin the build... the next hurdle? Getting it all home! Fiesta to the rescue...

Step 3: Cut Everything to Length

Now that I had everything on site to begin the build, I took careful stock of the condition of the materials. I decided what faces of what boards I would like visible in the final product and made easily removeable identifying marks on the board. I took careful measurements to ensure that the design on the computer would fit where I wanted it to go in the room, and so settled on a final dimension for the design. With that finalised, I started cutting the lumber carefully to the dimensions that I had produced using Rhino. Once the edges were cut I finished them with sandpaper, but the cut was pretty good anyway for using the fine point saw. I was careful to ensure all my cuts were square and tidy, and I always cut to the outside of my line to ensure that I had the complete length required.

Once the cuts were done I had a very small pile of offcuts - thanks go to the guy from the timber merchants for taking the time to ensure I had the right material for the job! I now had the lumber sitting ready for the next step...

Step 4: Part Assembly 1... the Long Rails

This part assembly operation was what I considered critical to the whole project. If these didnt work, the project would fail. They take the load of 2 people, a steel bed base and a heavy mattress and suspend them 1.8 metres above the ground - an onerous requirement indeed. I therefore spent a good deal of time considering how I could make these assemblys as strong as possible, while keeping them good to look at to fit in with the overall scheme of the project. I decided that the rails would be 50mm x 50mm section and they would be through bolted at regular intervals and glued to the long rails of the bed. I felt that this combination would give it the ultimate strength required, and by using coach bolts on the outside, the asthetic would not be compromised either. So, with the support rails cut to length, I spent some time setting up the position and the drill holes for 6 M8 75mm coach bolts that would hold the rails and clamp them while gluing.

With the bolts in place and a dry fitting carried out to confirm that everything would be ok, I applied a bead of Gripfill into the gap between the two parts. I then proceeded to bolt down the support rails onto the long rails and torqued them up a bit. I then cleaned up the squeezeout. I marvelled at how strong the whole assembly seemed! The whole process was done twice for 2 long rails, and then they were set asside for a day to ensure that the adhesive had time to set up.

With Part assembly 1 out of the way, I could progress to Part assembly 2...

Step 5: Part Assembly 2... the Bed Ends

The ends of the bed when built would need to be square and true to ensure that everything else fitted, so I spent time laying out the bed ends and ensuring everything was at 90 degrees to everything else! These were quite tricky to get right as i didnt have a big set square to use. In the end I used a large shelf from my desk to ensure everything was square. At this stage I made a template to ensure my bolting holes would be consistent around all four legs, and to ensure that there were no bolting clashes.

Once these 2 part assemblies were complete they were very heavy indeed - Reassuring me that the overall construction would be firm and sturdy.

Step 6: Major Assembly... the Tricky Bit

Everything before now was done on one day. The assembly of all the parts into the major assembly was carried out the following day when I had help available. It would have been difficult to do this stage on my own, but If I was careful and used lots of clamps I could have probably done it ok. With Nick available everything went smoothly and we had the final assembly done in about 2 hours.

We cleared everything out from where the bed would finally reside and set the Bed end assemblys into their approximate locations. We then used the template and held up the long rail assemblies, marked and drilled everything and placed some bolts in them. We carried on in this fasion untill we had all four corners of the bed bolted up. We used 2 bolts on each corner of the long rails and 1 bolt on each corner of the security rails.

With the bed all together, we then lifted it into final positions and torqued the bolts up to final tightness. The bed was an impressive sight, and the ammount of floor space that had been reclaimed was instantly clear. I was pleased.

WE then proceeded to the next step...

Step 7: Bed Base and Mattress

We lifted the bed base up and into position. It slotted into the recess made for it in the support rails perfecty - thank god we measured accurately! Happy with the fit, I climbed up for a try... A little wobbly as we hadnt braced it off anything yet.

We then got the mattress on and tried it with that. We were pleased to note that the dimensions as designed in Rhino were accurate, with the predicted 700mm above the mattress turning out to be 710mm! More is best... Also, under the bed worked out well with 1.8m under the long rails and 1.87 under the bed base, so standing headroom for me under the structure! Happy.

Next step? Bracing it off the walls.

Step 8: Bracing Off the Walls

I decided that my girlfriend was more likely to approve of the bed if it didnt move and didnt creak at all, so I devised a scheme to brace it off the walls in the corner where it stood. Using over long bolts, washers, nuts and pads I was able to really wedge the bed into position in a way that it would not move at all, infact, it feels like part of the wall! there is now no way it will ever budge.

Well, that concludes the structure and what I have done so far... the next step is to design a staircase/ladder up to the top deck.

Theres some finished photos in the next step.