A quick decking question

[johnnypanic]

Going to do an L shaped deck. Will attach to house via ledger, spaced 10 - 12mm from house, but was seeking advice regarding the 1 in 100 runoff.

Shoud I raise at the house end by 4cm (to cover 4m decking), or start ledger at the lowest point and have the 4cm at the garden end?

I'm concerned that if I do it at the house end, I will be too close to the dpc and if I do it at the garden end, the decking at that end will be below the garden level.

Or should I do 2cm at house end and 2cm at garden end.

Picture added to hopefully add some clarity to my question.

Thanks,

Johnnypanic

Untitled

• johnnypanic
• 25 Jun 2009
• 1

 

[peterlonz]

Even with the pic I am not certain I properly understand your concern.
It looks to me as though the grassed area you are replacing had very little natural fall & so creating fall in a concrete area laid in the same place will similarly have little natural fall, that is if laid level.
I would start by deciding that the existing pathway & the adjoining edge of the new slab should be at the same level so that a tripping hazard is not created.
Thereafter, if I assumed correctly that the ground is pretty much level, I would create a high spot in the centre of the new slab sufficient that water will be shed to all edges. This will overall be the same situation as you had before the slab but you will have ensured the slab will not hold water & grow moss slime etc in winter. Plus: you will find this a relatively easy job. Be wary not to finish too smooth, I think the usual finish is known as "yardbroomed" which is done just before set.
Good luck
Peter O

 

[Thermo]

its not an issue with the dpc, use some spacers to keep the ledger board off the wall

 

[johnnypanic]

I don't intend to concrete the whole area, but rather use paving slabs, spaced out to provide support for the joists.

The ground where the decking is being placed is pretty level, so as far as my thinking goes, I have a few options.

Lay the paving slabs so the entire site is level and incorporated the 1 in 100 run into the decking by raising at the ledger end.

Lay the paving slabs so that there is a natural run of 1 in 100 on the site, but if I do this, the decking at the garden end will be several cm's lower than the existing garden.

Or I could use a combination, i.e. raise the ledger and incorporate a smaller run off into the site.

Hope this makes sense

 

[WabbitPoo]

You are worrying too much - just jack it up at the house end. As Thermo says, the dpc is not an issue. I mostly build them level with internal floor so egress is nicer.

 

[johnnypanic]

Thanks for the reply, will take your advice.