Slab Questions - Help Needed

Perth-1st Timer · Jan 03, 2007 8:17 pm

Hi All,

Been lurking around these great forums for a while now and getting some great information (many thanks to all the more active participants!)

I have just started building in Perth and am now at the Slab down stage (Builder to remain nameless at this point).

I have some questions regarding my concrete slab and would love some opinions before I go back to the builder with a formal complaint.

1) The concrete is 'patchy' (some parts smooth - some parts rough) across the entire surface - is this going to cause any issues down the track?

2) The slab does not appear to be level - it has been raining today and when visiting the site this evening, the water has pooled up in certain areas (5 or so) - the worst being at the future main entrance to the home - I can feel the 'dip' as I walk over the area. We are going to tile the floor - will these 'dips' in the concrete be masked by the tiles or should I get the builder to rectify now?

3) There is a hole in the slab! Hard to believe but true - on a corner, the concrete seems to have fallen away before it set (which is bad enough) - immediately behind this is a hole (about 1cm diameter) which seems to go down quite a distance - I can squeeze a finger in there but can't reach the bottom...

4) There are as yet no footings in place for the garage walls or alfresco area - no need to comment on this one - I definately will be bringing this to their attention (Again!)

5) The 'wet areas' which are 'dug-out' a little more than the rest of the slab are incredibly * looking - not flat at all and very rough around the edges - will this cause issues down the track with tiling - or do the tilers cover up these imperfections when they do their job?

Well - thats all the issues I have for the moment - would very much appreciate any responses to the above as I am not having much luck finding Australian Content on the web.

Thanks and Regards
Perth-1st Timer

Dukekamaya · Jan 03, 2007 9:11 pm

The patchy areas are better for tiling as adhesive will stick better to the rough surface. Dips in the concrete will need to be rectified with a 'self-levelling; compound which can be poured over the floor. As for the wet areas, they are perhaps lower so a sand/cement screed can be laid over the top with a correct fall to the waste hole.
As for the finger size hole, I'd get the builder to investigate and make sure it isn't part of a 'honeycomb' system which will cause structual problems later.

bunoluvas · Jan 03, 2007 11:17 pm

You did say that no response in necessary however this may help...

From our experience I wouldn't worry too much about the footings for the garage or alfresco. We had footings for our portico, alfresco and garage go down a couple of weeks after the slab. This occured after the bricks were delivered and the bricklayers were onsite. Basically our bricklayers did some of our footings themselves and did it at the start of the job and worked towards it so that they were laying bricks on them at the tail end of the job.

We found that with rain there was always a couple of wetter spots. Remember though that your pad has just been laid so is to some degree already wet....proper curing can take a little while. Better to have it layed on a col wet day than a stinker! I know this is probably wrongbut we resisted walking on ours for about 4 days after (it was also wet weather when it was layed).

Regards

Perth-1st Timer · Feb 18, 2007 8:27 pm

Thanks to you guys who responded to this - apologies for not getting on here again sooner - however I did read your advice and it was invaluable.

The hole turned out to be a non-issue, and after inspecting numerous other pads it turns out that very few are even - still seems bizaar to me, but acceptable.

And thankfully footings have just gone down, so brick-work should start in earnest this week.

Cheers
P1T