Adult high level single bed frame from MDF

[Mr A R Upton]

Is it possible to make a bed frame for a 200kg adult that is only supported on the floor by 60mm X 60mm square legs in the corners. This will be over a bench so I can have a computer bench/table underneath and be able to sit under the bed to work and sleep in the bed above.

 

[Tigercubrider]

I wouldn't use mdf for the load bearing part.
Imho you'd at least have to make a bed frame out of timber, fit legs, then possibly clad with mdf for a smooth finish.
If you had access to a table saw you might be able to make box sections with 45° cuts on the edges and internal braces but timber with cladding would be easier.

 

[big-all]

if you are sure your talking 1/5th off a tonne or 4cwt/36 stone person then forget mdf off any sort and look at steels or possible scaffolding as a 7ft span will need a load off support
can you please double check the weight first? thanks

 

[Tigercubrider]

I didn't notice the 200kg!

 

[Deleted member 174758]

No! I've made bariatric chairs in the past (on contract, rated up to 60 stone or 380kg) and I can tell you that your material choices are inappropriate and your sectional sizes are completely inadequate. I'd forget steel - the required weight to take that sort of load might compromise your floor. What we used was solid ash (100 or 120mm square cross section) with foxed and pinned mortise and tenon joints and seat pad supports made from 22mm birch plywood (42in wide seats, we later did a bigger chair with a 60in wide seat). These chairs had to be tested before export to the USA in the main

 

[Mr A R Upton]

I was assuming the 200kg for the weight of a full grown adult plus mattress, sheets etc. For just the individual, let's assume 140kg instead (without mattress, pillows, duvet, sheets, coverings, etc a mattress alone is heavy and could reach 50kg)

 

[Mr A R Upton]

What I am trying to ascertain is normally soft wood slats about 1/4" thick are suggested for beds. But would 3/4" thick MDF provide the same support? Or even 1/2" thick? I know the same thickness will not work as soft wood is stronger. But how much stronger?

 

[Deleted member 174758]

1/4in (6mm) thick? I wouldn't even use that on a child's bed. You can get special structural plywood slats which are 6 to 10mm thick, but they depend on particular grades of veneer and glues not normally available to DIYers. Probsblyveasier just to buy in from someone like Hafele. Have you ever built a bed before?

When I've made beds (including the one I sleep in) the slats have been knot free 18 to 25mm thick x 80 to 100mm wide softwood. MDF is completely and utterly useless as slatting or in any other load bearing situation. Even 50mm thick x 200mm MDF will bend under load and can potentially break if subjected to shock loading, such as someone weighing 200kg falling onto the bed. I'd recommend that you consider a minimum of 25mm structural grade hardwood plywood (something like verola ply) for the frame (solid ash would be better) with an ash inner frame and a minimum 32mm thick x 125 to 150mm knot-free structurally graded ash for the slats to carry the loads you are talking about. After all 200kg is more than two adult men weigh

The reason why you need to over engineer on projects like this is because the shock loading of a 200kg person landing heavily on a piece of furniture is potentially great enough to burst joints and cause the furniture to fail catastrophically unless the right material and joinery techniques are used

 

[Mr A R Upton]

"After all 200kg is more than two adult men weigh"
I weigh 139kg so that is false!
I was guessing the slat thickness, but an IKEA slide out kids bed uses slat approx 6-10 mm thick and or not knot free either and they break (I had to replace two of them already)!
Still nothing about the relative strengths of soft wood verses MDF though. Please be helpful next time!

 

[foxhole]

"After all 200kg is more than two adult men weigh"
I weigh 139kg so that is false!
I was guessing the slat thickness, but an IKEA slide out kids bed uses slat approx 6-10 mm thick and or not knot free either and they break (I had to replace two of them already)!
Still nothing about the relative strengths of soft wood verses MDF though. Please be helpful next time!

You would not use slats but a solid sheet material as they are not strong enough , if you move across the bed your knee will be putting your total body weight onto one or two slats .

 

[big-all]

ok the way i normally make bed bases is 4x1"[21x94mm] slats at 55-70mm spacings but wouldnt rate it for 200kg even with a firm matress spreading the load??

 

[Diver Fred]

Bed I've just recently made for the MiL.
Slats are 3x1" spacing 1&1/2" joinery softwood (and I selected it myself in the wood yard).
Bearers 3x1/12 softwood.
Sides 3/4 beech ply - but that is standing on floor.

To meet your requirements
Rails (sides, head and foot) 5x2.
Legs 3x3 or 4x4
Slats (is this a single or double bed?) 3x1 (single) 3x1&1/2 Double spaced 1&1/2 apart. I'll disagree with Foxie - solid sheet for mattress will spoil the mattress as it needs ventilation to stop damp.

 

[foxhole]

Bed I've just recently made for the MiL.
Slats are 3x1" spacing 1&1/2" joinery softwood (and I selected it myself in the wood yard).
Bearers 3x1/12 softwood.
Sides 3/4 beech ply - but that is standing on floor.

To meet your requirements
Rails (sides, head and foot) 5x2.
Legs 3x3 or 4x4
Slats (is this a single or double bed?) 3x1 (single) 3x1&1/2 Double spaced 1&1/2 apart. I'll disagree with Foxie - solid sheet for mattress will spoil the mattress as it needs ventilation to stop damp.

Wheres the damp coming from, unless your incontinent?

 

[Diver Fred]

Wheres the damp coming from, unless your incontinent?

Sweat etc.

 

[Mr A R Upton]

Sweat etc.

Yes. And breathing etc. Normal body processes. I also know that due to a slatted bed I used to have that then had hardboard placed over the slats, caused mould to grow. The mattress needs to be flipped EVERY day to stop this. At least with breathable slats, the mattress doesn't need to be flipped for weeks.