A good way to build raised decking?

[gregbbb]

Hi all

Just wanted to pick the brains of the experts to make sure I'm doing this right. I want to build a raised decking area on the patio shown below.

I'd like it to be as close to the level of the french doors step as possible so as to eliminate the step down from the lounge and the step up to the lawn (what's left of it!).

So, the height would be about 300mm above the current patio level. The frame would be about 4m x 2.5m.

I really don't want to dig holes and start concreting posts in so I thought about making a frame from some 6x2 and resting this on 6 mounts made from paving slabs and a few bricks. i.e. patio, then paving slab, then bricks, then frame sitting on top. This should get me to a height of about 300mm.

The mounts would be spaced approx 2m apart lengthways and 2.5m widthways.

Is this all viable?

Should I also fix the frame to the exterior wall? Or will it be ok just resting on the mounts.

A few other bits I guess I will need....

- DPC sheet to prevent weed growth.
- DPC in between bricks and frame to prevent rotting of frame.
- If the frame is fixed to the wall then as it will be above the wall DPC then I should use some shims to eliminate contact with the wall.

I've read and read on this subject but I havent seen many examples of mounting the frame on slabs/bricks so any tips for this would be great.

Cheers all!

 

[Thermo]

if youve got that room to play with use 6 x 2 bolted into the walls alround. you may need some supports across the middle. Use some 6 x 2s as posts down from the frame resting on the slabs.

Dpc and decking is not really an issus, but if youre worried you can shim it out.

Use a landscape fabric not dpc.

 

[gregbbb]

Good idea Thermo!

A few queries though....

- Would bolting the frame to those retaining walls affect their stability in any way? Would it put any unnecessary strain on them?

- Could the vertical posts that support the middle of the frame be in direct contact with the current patio slabs?

- What is the best/easiest way to fix the beams on the inside of the frame to the frame itself? Screw from the outside inwards before attaching the frame to the walls? Or use joist hangers after attaching the frame to the walls?


Cheers in advance

 

[freddiemercurystwin]

Surely a cheaper and easier way would be to sit your 6x2s on a 5x2 (or 4x2s depending on the heights) subframe. Assuming the existing patio's fairly level/not loose the whole thing would just sit there with gravity holding it down. They'd need to be screwed to each other but no bolts or fixing to the wall and no drilling.

 

[gregbbb]

Thanks for your reply freddymercurystwin.

I did consider that initially but assumed a few slabs and bricks would be cheaper than another frame underneath. Now it seems some bolts would be cheaper than both. No?

 

[Thermo]

Surely a cheaper and easier way would be to sit your 6x2s on a 5x2 (or 4x2s depending on the heights) subframe. Assuming the existing patio's fairly level/not loose the whole thing would just sit there with gravity holding it down. They'd need to be screwed to each other but no bolts or fixing to the wall and no drilling.

no because it wont be level and it will rock. you will be biulding twice the franme you need.

rawlbolts wont put a strain on it.

yes the posts can bear directly on the slabs providing they are not lose.

you can either use joist hangers or skew nail/screw them.

Thats how we do them, trust me we do a lot of them!

 

[masona]

bashdem, I can't see any drain outlet to collect the rain on the ground

 

[freddiemercurystwin]

Surely a cheaper and easier way would be to sit your 6x2s on a 5x2 (or 4x2s depending on the heights) subframe. Assuming the existing patio's fairly level/not loose the whole thing would just sit there with gravity holding it down. They'd need to be screwed to each other but no bolts or fixing to the wall and no drilling.

no because it wont be level and it will rock. you will be biulding twice the franme you need.

rawlbolts wont put a strain on it.

yes the posts can bear directly on the slabs providing they are not lose.

you can either use joist hangers or skew nail/screw them.

Thats how we do them, trust me we do a lot of them!

If its shimmed you can take up any slack, my deck has nothing but gravity holding it down and it hasn't moved in 7 years and thats a 3X2 subframe with 18mm decking so not even that heavy. The subframe underneath need only be say 3 lengths as you've got 6x2s on top which will span that easy. All that drilling and the cost of joist hangers/rawbolts seems avoidable to me.

 

[Thermo]

id still rather do it my way. 20 rawl bolts wont cost much nor will the joist hangers. its off the ground, will last years, no chance of movement and wont really take any longer to do. Each to their own!

 

[freddiemercurystwin]

fair point

/tips cap

 

[Thermo]

and i doff mine to thee yea verily!

 

[gregbbb]

bashdem, I can't see any drain outlet to collect the rain on the ground

No, there isn't any

I've had a butchers at all my neighbours gardens and they don't have them either. Is it necessary?

Where would be the best place to put one if I have to?

 

[ColJack]

does the patio flood as it is now?

if not then there's no problem..

if it does the since you are decking over it, find the places it pools and put a 2 inch core drill through the slabs and into the dirt to let it drain away..

 

[masona]

bashdem, I can't see any drain outlet to collect the rain on the ground

No, there isn't any

Find the lowest point then put in a soakaway

 

[gregbbb]

does the patio flood as it is now?

if not then there's no problem..

if it does the since you are decking over it, find the places it pools and put a 2 inch core drill through the slabs and into the dirt to let it drain away..

No, there doesn't seem to be any flooding at the moment. I think the patio has been down for some time and there doesn't seem to be a history of problems.