Composite Decking 4.8m x 30mm

29 Feb 2012
Reaction score
United Kingdom
I have a balcony that is in the process of been replaced.

I have planned to put composite decking down to try and reduce maintenance.

My problem is: I have 5 support beams protruding from my house, they are each just short of being 1 metre apart. with the total distance being 4.8 metres.

I am therefore looking for composite decking that can straddle the ~1 metre span without sag and ideally have no joints.

I have tested this at a local building supply and their 25mm thick hollow section sags a lot (see pic).

I have since sourced 30mm hollow section but doesn't come in 4.8metre lengths.

Does anyone know if 4.8metre x 30mm or thicker lengths exist?

IMG-20170811-WA0000.jpg IMG-20170811-WA0001.jpg IMG-20170811-WA0002.jpg
Sponsored Links
Sponsored Links
won't you need building control and structural calcs? That is quite a height to risk falling from.
Even if the house was already built with a balcony?

I'm only replacing what was already there, obviously not going to fit anything that's dangerous on my own house.
Last edited:
You could add extra timber in between existing to reduce span or overboard with ply, then you can use any thickness of board on top .
So the builders that built this house in 1970 were potty?

And the balcony that I used until I decided to replace it was unsafe?

I'm only trying to replace something that stood for 47 years, and the house had planning permission with the balcony.

If I can't replace it with composite then I'll go for thicker timber decking.
I don't know, you've not told us! Maybe you could enlighten us? Is it timber then? If so how thick is it?

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.

Are you a trade or supplier? You can create your listing free at DIYnot Local

Sponsored Links