What thickness plywood for cellar cover

[bandejapaisa]

I'm going to build a cellar hatch. It's 735w x 1420l.

It will have hinges on the long side and I'll be getting 2 gas struts to hold it up when opening (like a car boot).

Along with the ply, on top of it will go 6mm ply + 20mm engineered wood floor - this is to keep it the same level as the rest of the floor when that gets done.

My question is, what thickness ply should I use? An adult couldn't walk on it, because of the head height, but my little kids might. And should I use hard or soft wood? I'm conscious of making it too heavy for the gas struts - I will need to specify the weight to the gas struts people at some point.

 

[foxhole]

25mm ply should be strong enough, would not use gas struts sudden failure could be dangerous, better to latch open with a length of chain or steel hook.

 

[bandejapaisa]

The main reason for the struts is for taking the weight out of the lifting. What's the chance of both gas struts suddenly failing - surely as dangerous as every car boot and bonnet out there. Anyway...

I could always complement the struts with a safety chain.

Thanks

 

[foxhole]

Your trap door is going to be heavier than most car doors, only one strut had to fail to cause collapse.You could use a counter balance to reduce weight when lifting.

 

[bandejapaisa]

Do you reckon it will be heavier? Car boots are pretty heavy - especially on older cars with heavy metal and glass etc... I'll report back with a weigh in.

Anyway, like you suggest... i'll add a safety mechanism.