Looking for some advice. We have just brought a house with a raised decking area. We have a inflatable layz spa jacuzzi and was thinking that it would be good on the decking, but, I was wondering if the deck would be able to hold the weight of the water and upto 4 people? I'm a useless when it comes to diy..

Merry Christmas 🎅

Looking for some advice. We have just brought a house with a raised decking area. We have a inflatable layz spa jacuzzi and was thinking that it would be good on the decking, but, I was wondering if the deck would be able to hold the weight of the water and upto 4 people? I'm a useless when it comes to diy..

Merry Christmas

Bit of science for you... If you get a swimming pool and fill it to the brim, then climb on in, water will slosh over the edge, that water will equal your own weight (provided it is indeed yourself that climbs in...-_-)... Eureka an all that..

If you know the water capacity of the jacuzzi you can work the weight of the water.. 1 metre cubed = 1000kg's... Then find a load of adults and stand in that spot...

I suppose the only way to know would be to have a look at how it's built and the materials and sizes..., or find out by trial...

I suspect it's probably fine, given the amount of people that can normally fit on decking...

Lift some of the decking boards and see how its been constructed. How high is it raised? If its just timbers on edge laid onto flags then that would be plenty strong enough. If its raised more and supported on uprights concreted into the ground then it all depends on how many supports there are and if it has good coach screws/bolts fixing it together rather than normal wood screws. I would say its impossible for anyone to give you a definitive answer without seeing it to be honest.

I would be inclined to add extra supports and spars underneath to spread the load, just to be on the safe side.

when i done my deck i used spikes into the ground,when i decided to put a easy up pool on it which held at least 3k litres of the wet stuff it dropped 1 end,so i had to jack that end up and instal some extra supports.

my joisting was 6x1 doubled up at 400 centres,

im a chippy,

the timber didnt give,twas the ground lol.

it lasted for about 10 years putting the pool on it,sadly this year i had to rip the lot out as we needed the area for a car to be parked on it.

Its hard to describe really. The decking is above a shed (the bit where I want to put the spa), so its about 6.5 foot off the floor but this area is supported by concrete block walls as that what the shed I made of.. I will try get a picture on Monday on my next day off.. It will probably make more sense I think.

Its hard to describe really. The decking is above a shed (the bit where I want to put the spa), so its about 6.5 foot off the floor but this area is supported by concrete block walls as that what the shed I made of.. I will try get a picture on Monday on my next day off.. It will probably make more sense I think.

Not knowing what is happening below the ground, or what the walls are on, isnt ideal, but if the walls are OK then it's now onto the decking and the spans, size of the wood etc etc..

Well the house is built on a cliff and a structural survey has confirmed that it's built on rock so hopefully the walls are built on strong stuff haha

Here is a few pics of the outside wall and what the underneath looks like from inside the shed

So really the question was could i put a jacuzzi on my shed roof? I would say no sorry by looking at the supports. It would be a heck of a weight once full of water and people. I would want to put extra upright support columns in there to support the joists. Im no structural engineer though.

There is a lot of depth in those joists.... The spacings look quite big though, and the span looks fairly long...

If you figure out the amount of water the pool takes then you can get your weight that'll be sitting on that roof...

They look like the size i have upstairs in my house and i wouldnt try putting a jacuzzi in my spare bedroom for fear of getting in it and landing in the kitchen below!

They look like the size i have upstairs in my house and i wouldnt try putting a jacuzzi in my spare bedroom for fear of getting in it and landing in the kitchen below!

There is obviously more water and therefore weight, however if you consider the amount of water in a bath (1 cubic metre of water is a ton), joists have a considerable weight limit.

That being said, there are no guarantees with my online opinions

To be fair, that looks fairly strong enough, maybe i'd whack a few more bolts into the wall and maybe for extra security just put some joist webbings between the joist runs that way it should give you your best outcome. You'll be surprised how much of the weight is carried along the wood as apposed to "going down to earth"

Set a camera to record in the shed when you fill the jacuzzi up and get in it, when you come through the ceiling still sat in it then it should get you a few million Youtube hits generating some cash to pay for the damage!

The spa holds 848 litres which I believe is 848 kg then the weight of up to 4 people. On top of the roof you see inside the shed is a layer of decking boards too

Are the joists sat into the brickwork too or solely resting on the horizontal timber fixed to the wall?

The ply did make me wonder a little, if the Base of the pool is solid then the weight should in theory be spread across the joists, if it's soft then any slight deflection in the ply and then you'll start introducing further forces and more weight to just the ply.... (which is fairly strong I suppose)....

Remember archimedes!

im surprised there isnt any solid noggins in that floor anyway,to stop the joists from twisting.

the joist look to me from the pics that there a little on the wide side?

if it was mine i would put a few more joists in and maybe a few steel plates onto the joists aswell to stop deflection.

ask here

www.diynot.com

You could use some acrow props and some steel beams to reinforce the structure.

Are the joists sat into the brickwork too or solely resting on the horizontal timber fixed to the wall?

The joists look to be resting in the brickwork, I think..

That looks a bit too neat to be in the brickwork, more likely the joists are notched on the ends. Looking at picture 2 though it does appear to be the horizontal beam taking most of the weight with a small notch in the joist sharing a bit of the load onto the blockwork. It would definitely want additional upright supports from the floor to the joists if it were mine.