I forgot my DPM!!!

[Skavenger]

Hi;

So I laid 150mm hardcore and about 50mm sand binding and then in my haste today I started to lay the concrete without first putting down the DPM!!!!!!!

Anyway we only managed a first layer of about 40 - 50mm out of 100mm and have a second session at it tomorrow to get down 100mm all over.

Questions:

1. Would it be OK to lay down the DPM so that it is sandwiched in between the two layers of concrete or would this make the top layer of concrete to weak?

2. Do I need to lay down some more sand (the concrete has been tamped flat, its not smooth but no obvious sharp poky out bits).

This is a 3 x 2m shed / workshop so not being driven on.

 

[tony1851]

If it's a shed/workshop, can't you make the top concrete 100mm thick?

 

[Skavenger]

If it's a shed/workshop, can't you make the top concrete 100mm thick?

I've got about 2/3 bag of ballast and intend to use it all up so it woul probably be about 80mm.

 

[Nige F]

80mm will be ok. so will the dpm on the concrete, no sand

 

[Skavenger]

80mm will be ok. so will the dpm on the concrete, no sand

Ok thanks. Really annoying that I forgot it especially as I had taken so much care prepping the hard cores and sand binding!!!

 

[Nige F]

No one will know and it's not needing building regs.