Anyone know much about decking, or how to lay foundations etc?
 

Hi all

Starting a decking project in the back garden in a couple of weeks time. Its a ground level deck (that will be raised off the ground an inch or 2 for damp clearance).

I've done quite a bit of research into it and it seems to be that the best way to lay foundations for a ground level deck is to dig a 6" square hole in the ground, fill it with concrete to a couple of inches above ground level.

However as I need 13 seperate foundations, getting 13 wet concrete posts all level with each other isn't going to be easy!

Would it be acceptable to dig holes in the ground, drop in some strong plastic tubing, (6" soil pipe for example), get all these level, then fill these with concrete?

Thanks in advance

Rich :)

Should be able to get it pretty close if you set it out well enough?

Am i getting this right: wood posts on top of the concrete piles? Trim the wood to the right height?

Thats right, the wooden joists sit on top of the concrete foundations to keep it off the ground to prevent it rotting :)

Its just getting all 13 wet concrete piles the same height as each other that i'm going to find difficult!

Cool, I get it now, I was thinking posts for some reason :cry:

Well, concrete isnt going to just sit 2 inches above the ground until its dry, so I would dig the holes, then use some shuttering ply to line the hole, which you can then level up before filling.

Basically the same idea as your 6" soil pipe idea. Only square.

(You could use some slate as a packer if one of the concrete posts is too low etc)

Also, string lines will help massively for you to work from your datum.

Ok great stuff cheers for that mate!! I presume I would have to make 13 of these shuttering ply things? Then just knock them off the concrete once its set?

Yeah you would have to make all of them.

Might be easier to use your idea of 6" soil pipe tbh, you could buy a length and chop it down loads quicker than cutting ply.

or leave the shuttering in the grund as it's going to be a bit of a pig to get out, seeing as you'll have to dig it out :)

soil pipe might be easier although probably more expensive depending on how much you want to set, 26' of pipe might cost more than 2 sheets of ply which will do you your 13 posts at 2 feet deep

http://diydata.com/materials/manmade...nmadeboard.php

gives you some idea of what's what

it's a box to pour the concrete into while it sets, like this

http://www.europlywood.org/cms.taf?A...ywoodOrgXXX725

The ply will eventually rot and break up though Dojj, I would make the holes big enough to have a little room to play around the edges so you can take the shuttering off and backfill the soil up to the concrete.

big holes means more digging :cry:

although he oculd make big holes and then use a few noggins to brace the ply while the concrete sets making it easier to remove afterwards

but a lot of work as opposed to forking out a few quid for the 6" pipe

Cheers for the replies!!

Will probably stick with the 6" soil pipe (or as big a diameter I can get) and fill them with the concrete, then backfill outside the soil pipe with concrete too up to ground level just to make sure it isn't going anywhere :king:

how we do decking is make the frame up. place it where you want it to go.mark the holes up then set fence posts in the ground with post fix.then you can level the deck up to what you want on the posts as the will be allready set.then chop the top of posts off.

real easy mate.ive done quite a few.

I did a pretty big deck - never done it before.

Plotted out the 4 corners first, dugg 2ft deep holes and stuck 4x4" (iirc) posts in, bedded the bottom with soil to get them steady and square, Then slapped in the post mix, five minutes it was set.

Then worked more posts in between, then used joists, then ran the decking the opp way.

Job done

Blimey, there's another spanner in the works :cry:

It certainly would make it easy to make the frame first I suppose, the deck i'm making isn't a simple square so I guess this would help with where to make the foundations.

I looked into using posts, however it seemed that it was un-necessary to use them on a ground level deck - may reconsider this though if it seems to be the preferred option? I guess it would be a lot sturdier than just having it sat on concrete blobs sticking out the ground.....

You chaps got any pics of your decks for a bit of inspiration?

Thanks

Rich :)

Good point :cry:

I think the pipe idea is good, though the frame idea is a good one too, you will have adjustability with wooden uprights :king:

Wooden uprights are currently getting my vote i think!

Is it best to fix the decking to the house, or leave it 'free standing'?

Thanks :)

I dug out my garden and sloped the ground.
I lay plastic sheeting (DPM) over it and threw on chuckies to keep it from blowing away.
I built a wooden frame, so the decking would be screwed directly to it. The frame was laid and supported throughout with a level concrete couple inches wide wall.
It saves having to lay a large concrete slab that is a cunt to get level (if you haven't done it before)

The water simply lands on the DPM below and seeped down to the bottom part of the garden (into the flowerbed)

That was my first project on my first house that I was so chuffed. Unfortuantly, I never took any in-progress photos to show you. :(

http://i24.photobucket.com/albums/c2.../IMG_0031s.jpg

http://i24.photobucket.com/albums/c2.../IMG_0029s.jpg

Looks good that, cheers for the info mate :)

When i lay decking just above ground level i always use solid concrete blocks as pads to sit the joists on.
Work out where you joists are going to be and set the blocks in where required setting them on a wet cement mix. Just level from one to the next and so on, digging out to leave top of block 2 inch above ground level.

I did also think of that one - glad someone else has mentioned it! Any problems about the blocks cracking or anything?


Rich :)

As long as you bed them on enough cement, bigger area than block, they won't crack.

i've done plenty of decking and used a variety of methods. the simplest, if the ground is reasonably level, is to set out blocks on a thin pad of concrete as mentioned above. if the ground is uneven or sloping then the method of timber posts set in concrete is better, that way as the bearers/joists are fitted the tops can be trimmed off before the deck boards go down.
once the supports are laid out cover the area with a permeable membrane/ landscape fibre to suppress weed growth, you can then cover that with pea gravel to stop the wind lifting it.
its best to screw the decking boards down as opposed to nailing as can nails will work loose.
a bearer/joist can be fixed to a wall with rawlbolts.
remember that the finished height of a patio or decking should be 150mm (2 brick courses) below the damp course if against a building

Thanks for the advice dan! I probably won't fix it to the house, no doubt that will just open up another can of worms, and its a lot easier to remove if for any reason it needs to go in the future.

Off to pick up all the materials tomorrow, my work berlingo aint gonna know what has hit it :cry:

this might sound a lil dum but you didnt say if the decking was goin over grass or over paving. i you was goin over paving i would just use a post plate that can be bolted down to the floor (ancor bolts) then put the wood in the base pale, screw it in and off you go.

Lol thats a good question actually, its going over paving, grass and gravel :cry:

Its all going to be removed first anyway :)

its just a shame you dont live closer, i could have got you some wood for the job for FREE unless you wanna come to manchester for it lol

Shame that, manchester is a little far!!!

Cheers anyway :king: