Wooden decking over uneven concrete 3.2m x 2.1m

[steveb77]

I would like to install some decking over an unsightly concrete slab in my back garden.
The slab is made up of smaller sections and is uneven with a slight gradient.
I have lots of spare paving slabs or bricks I can use as piers.

What is the easiest way to construct the frame?
Would I need to fix the slabs/bricks to the concrete with mortar?
Would I need to fix the frame to the bricks/slabs?

Any help would be much apprciated.

Many thanks.

 

[steveb77]

Here is a pic of the area:

Untitled

• steveb77
• 3 Apr 2012
• 1

 

[Arthur2shedsJackson]

I personally don't like laying on previous surfaces such as this, because there may still be some movement ( You don't know how good the base under the paving is.

However, if you are going ahead, my advice would be to find the highest point of the existing and shim the frame up to level it to that point.

There should be no need to fix the frame down to the concrete/paving slabs, as the weight of the deck should keep it in place.

As for the best way to constuct the frame, see the link below
http://www.diydeals.com/Assemblyinstructions.htm

and for fixings

http://www.screwfix.com/p/timber-tite-joist-screw-6-5-x-80mm-pack-of-20/95586

http://www.ebay.co.uk/itm/50-200mm-TIMBERFIX-HEX-HEAD-SLEEPER-SCREW-TIMBERLOK-/190416553661

You will need 120mm long, I would suggest, if you are using 4" x 2" or 6" x 2" joists.