Reinforced Decking

[Danny-r]

Hi Guys,

 

We're having some decking put into our garden, over an area currently grassed. I've attached an old picture as I'm not very good at describing it, but basically full width starting from the grass nearer the house, 3m backwards. A rail would also be put in.

 

We're planning on putting a shell hot tub on the left, which will weigh ~2 tonne, about 2m x 2m. Of course, our concern is support, we've had 3 quotes so far and each person disagrees on how best to provide support, so I thought I'd reach out for opinions!

 

1. Dig the turf up, lay sand etc and build up to paving slabs. Then put the tub on the slabs, then deck around it.

 

2. Lay a metal frame, fill with concrete and then deck around that. Small 18mm hole to drop tub into, onto the concrete.

 

3. This one reckons he can put the weight and dimensions into his CAD program and then ensure sufficient support by using more joists. This is our preferred option as we'd not like to be rushed in terms of when we get the tub. He's asked for the exact model so he has the dimensions and weight, and claims he's done it before.

 

Ideally we'd put it not on the grass, but there's nowhere.

[Temp]

First you need info from the tub supplier on the support required. Do the tubs have a frame that must be supported or must it be supported everywhere? Ask them about use on decking as they may have a recommended joist layout or other advice. This may feed into option 3 nicely.

 

I'd be a little concerned about putting 2 ton right close to the retaining wall (option 1)unless I was sure that retaining wall was up to the job. For same reason I think I'd want the posts supporting the deck either very deep or on the house side of the retaining wall.

 

I would sleeve all wooden posts with post saver or even galvanised steet metal at ground level to protect the thin pressure treated skin from accidentally wear by strimmer. Better still use metal below ground and keep all wood off the ground.

 

This sort of thing but shop around as they look expensive..

 

https://www.ebay.co.uk/itm/Stainless-Steel-Timber-Fence-Post-Shoe-Post-Support-100-x-100mm-Square-Posts-/193679535664?var=0&mkcid=1&mkrid=710-53481-19255-0&campid=5338268676&toolid=10044&customid=CjwKCAjwmeiIBhA6EiwA-uaeFTsUfcqgJi-7rzjHx3YQfElN1zW8P7Cw3NElOP_hhgbkS4J48pkioRoC0JIQAvD_BwE&redirect=mobile

 

 

  

 

 

 

Edited August 16, 2021 by Temp

[Ferdinand]

I would be looking with a jaundiced eye, and reflecting on what is under that raised lawn (is it real grass?), just in case you need to excavate into it for foundations or anything.

 

I looks newbuildy, and I wonder where they put any rubble?

[Ferdinand]

7 minutes ago, Temp said:

First you need info from the tub supplier on the support required. Do the tubs have a frame that must be supported or must it be supported everywhere? Ask them about use on decking as they may have a recommended joist layout or other advice. This may feed into option 3 nicely.

 

I'd be a little concerned about putting 2 ton right close to the retaining wall (option 1)unless I was sure that retaining wall was up to the job. For same reason I think I'd want the posts supporting the deck either very deep or on the house side of the retaining wall.

 

I would sleeve all wooden posts with post saver or even galvanised steet metal at ground level to protect the thin pressure treated skin from accidentally wear by strimmer. Better still use metal below ground and keep all wood off the ground.

 

This sort of thing but shop around as they look expensive..

 

https://www.ebay.co.uk/itm/Stainless-Steel-Timber-Fence-Post-Shoe-Post-Support-100-x-100mm-Square-Posts-/193679535664?var=0&mkcid=1&mkrid=710-53481-19255-0&campid=5338268676&toolid=10044&customid=CjwKCAjwmeiIBhA6EiwA-uaeFTsUfcqgJi-7rzjHx3YQfElN1zW8P7Cw3NElOP_hhgbkS4J48pkioRoC0JIQAvD_BwE&redirect=mobile

 

 

  

 

 

 

 

If you buy Postsaver (which I use on all posts) go and buy direct from the manufacturer via there website as it is about 30% of the price resalers will charge you.