Extending garden base

6 Apr 2015
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United Kingdom
Hi all.

Hoping someone can help me with some advice about extending my shed concrete base.

- current shed base is 4" deep and 6x6 and would like to extend it on one side only to 6x8.
My plan is this.
Hammer two rebars into existing base 50mm from top.
Shutter up one side of base and remove all earth. (Question- what's best sized timber to use to shutter? What's best method of securing shuttering to existing concrete base?)
Put down a layer of hardcore. (Advice on best hardcore to use and how much)
Lay down concrete 2" thick to bring level with existing base.
Level off and cover with plastic sheeting to dry for a week.
Am I missing anything else here? The shed will be a wooden one with some bikes in it and some gardening tools.

Advice would be appreciated.
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Thanks KRB78.

JUst need to know the best method of securing the shuttering to the existing concrete and what best sized timber to use for it?
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what about pegs behind the shuttering and then nailed to the shuttering and id prob say slightly thicker the better to stop or minamise bending but again a wooden peg in the ground near the weak point should sort it out. 10-15mm wood width?

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