Slab design - garage lower than ground level

[ltr]Hi All,[/ltr]



[ltr]Question on slab designs - to meet garage height requirements our builder will need to lower my slab in the garage, resulting in the garage to be 86mm below ground level. [/ltr]


[ltr]Anyone been into a similar situation before?[/ltr]


[ltr]I'm a bit concerned about potential flooding in the garage due to being lower than ground level. How did you get around this?[/ltr]

Garages are traditionally always built one step lower than the house.
Why are you worried about flooding? Better that you only flood the garage than the whole house!!

Hi, I thought when they said lower than ground level it meant lower than the surrounding ground soil level outside, not lower than the ground floor of the house, that's why I was concerned of the flooding as water might get in when it rains.

Building the Votivo43 - viewtopic.php?f=31&t=88553

Hi g33kerb0t,

I had a quick look at your build thread, so it seems your land might not be titled yet, so do you not have a site plan with ground levels?
I would also presume they mean its a step down into the garage from the house, but not below the finished ground level.

Hi,

Sorry my build thread is not up to date
Land has titled and settling tomorrow.

I have the site plan but it isn't finalized yet. There's still some discussions with the builder regarding changes to the site plan.

Building the Votivo43 - viewtopic.php?f=31&t=88553

If you are seeking advice It is in your best interest to keep your build threat up to date
Your builder will adjust the levels to suit him, this may not suit you for work that you may have to do after handover, ie storm water, Runoff, Retaining ,etc.. since you only get one go at getting it right please post up the contour site plan, levels,etc for considered advice. hth

Thanks. I'll post it as soon as I've got it back from the builder.

Building the Votivo43 - viewtopic.php?f=31&t=88553

Hi Guys,

We have been told that due to higher fall on our block, we are going to have 2 steps in the garage to access home from garage door or do not obtain internal access garage door.

Without having 2 steps, It would be one big step to gain access inside.

Any thoughts or did some one come across with this issue ?

Hi Wild,
I don't think its a problem to have two steps, it may mean you have a higher ceiling in the garage which I think is handy.

Thanks mate

The issue is that the slab level of garage is lower than surrounding ground level and that there may be a risk of flooding. A competent designer will set levels to either avoid that scenario or if it cannot be then ground levels be modified to be lower or if that is not practical to provide for effective drainage. I all cases there must be compliance with NCC.
One of the things I check for in pre contract review is house levels in relation to ground and drainage. Many times I have advised the client to go back to the builder for review of design levels.