Concrete slabs for patio/decking base

planforfuture

I am looking to replace my current rotten floating decking (approx 15m sq) with a solid base (i.e. non floating) and then I will put onto that base with WPC/Polypropylene plastic deck tiles myself.
For the decking base, I like the simplistic (strong and cheap) of British Standard concrete paving slabs (ard £6 per 600x600x50mm ea) and think it will provide a solid foundation/base for a deck. Think it maybe cheaper to lay than other materials e.g clay bricks. I am also exploring cheap alternative solution for the base - PLEASE ADVICE.
I estimated that the concrete slabs will cost me about £250 and wonder how much it will cost from a builder to clear the current deck, flatten and prepare the ground and then lay the slabs?

FreeBear

I had a company that specialises in groundworks to dig out & level a similar sized area and then put down ~100mm of hardcore. Bill was just under £1K.

Laying the slabs, I spent another £250 on sand & cement and laid them myself - Tip - Use a cement mixer and a wet mortar mix (you can get away with a 10:1 sand/cement mix). Hard work, but if paying someone to do all of it, I'd say around £3K. But don't use anyone that will bed the slabs down on dollops of mortar - It needs to be a full bed or the slabs will move & crack. This site gives some valuable information on doing a "proper job" - https://www.pavingexpert.com/

A couple of points - Make sure the finished level is ~150mm below the DPC of the house, and don't lay the slabs right up against the wall. Leave a 200mm or so gap and fill it with gravel.

planforfuture

I am thinking of getting someone to prepare the ground and then lay the concrete slabs on top. How much do you think it will cost labor and materials wise (e.g. sand gravels etc for the base)?

FreeBear

£3-4K (depending on town - London rates, double). Sand, cement, and hardcore, allow £400 if tipped loose. On top of that, add the cost of slabs, and budget for a few breakages. Then there will be two or three skips needed to take away any waste (£200 each ?) unless you use a grab hire firm.

planforfuture

WOW. For that price, it is probably much cheaper (think ard £2k all in) to replace the deck with another floating deck with WPC. Just wonder if there are any alternative cheaper options for the base?

FreeBear

I doubt very much that you'll find anyone to do a "proper job" for £2K all in. For that sort of budget, you'll need to do much of the work yourself. Perhaps hire someone with a minidigger to do the heavy grunt work digging out & leveling.

planforfuture

Yes probably right. Maybe just a concrete patio and then I pay the deck tiles on top.