Skirting around New House Slab

Hi OzBargain crew,

Coming to you for advice. I'm trying to research what the job I want done to my near new house is called.

Essentially, the house is a wood frame sitting on top of a concrete slab. It looks like the job may not have been fully completed as the house seems to be floating above the slab as it protrudes by about 10cm. Photos

I've seen similar new houses that have some sort of cover on that bottom part. I would like to know what that part of work I require is even called, as I know nothing about construction. I would then either DIY something or get a builder to come do it properly is it's important to the longevity of the building.

My questions:

What is that called?
Is it an important to have that sealed off?

Looking forward to you help!


  • I'm not in the building trade at all but that looks dodgy AF to my untrained eyes.

    The framing overhanging the slab to me would indicate the slab was constructed too small and the framing was likely prefabricated offsite and the builders just "made it work".

    It must be acceptable otherwise it would never have been signed off. For all I know it could be a new cost saving technique when you aren't building a brick veneer home.

    I gather you need a plinth of some sort to cover it up but that would probably look even more shite than it already does and create airflow / moisture retention issues.

    I had to zoom in on your plants/weeds in the second photo but it would appear you're all G.

    • Thanks for taking a look. I agree it doesn't look the best but doesn't really stand out unless we look at it hard ;)

      A plinth to cover it up should help

  • +1

    Hard to tell, but looking at the distance the window is in from the outside of the wall cladding I would assume that the timber you can see from the lower picture is just a batten to pack out for the wall cladding, not the actual bottom plate of the frame. Not really dodgy at all. The timber piece you are asking about is called a plinth board.

    • Thanks for your input. The wall has extra insulation all around due to it being near a noise corridor so I suspect you are correct, it is double cladded all around and hopefully this is just retention.

      I'll look around for plinths to cover it up and make it look neat

  • ask on they have experts in building trade.

    • Thanks pencilhead. Didn't know about that forum but I've always used ozbargain for advice over the years, as it attracts people of all professions and I'm keen for general impressions and advice, even if they aren't from full experts sometimes

  • They probably should have put a metal angle (alu) around the bottom edge and run the external FC sheet a little lower for a drip, rather than virtually finishing flush with the batten. Even a plaster bead to neaten it up would be better and provide a drip groove of sorts.
    The dark stuff hanging down is likely flashing/sarking which is essentially a waterproof layer to keep water away from the building that might get in through the wall.

    As long as you maintain a gap to the ground/dirt you should be alright. You don't want any moisture seeping into the (timber in particular) from dirt or puddles so a plinth board may not be the best idea if it will touch the ground.

    Interesting that you have a double sheet layer on your wall - I guess it's acoustic as you suggest but not the typical way to solve the problem. Was this a variation late in the build? They probably should have pushed out the slab rebate a little larger to account for the extra batten/sheet depth.

    General principal to sticking anything to your building at a low level is keep water out - so keep any plinth you might apply above the paving slab/dirt, have a slight fall away from the building to all top faces, and make sure it is a water resistant material.

    The house slab being above the surrounding paving slab is 100% normal and basically a requirement for compliance.

    It's a tricky area to detail well so a low-cost builder can get away with an 'unfinished' look as your pictures show.

    • Thanks for the in depth advice! I will take note. The roof overhangs the sides of the house quite a bit so the walls don't usually get wet at all, so perhaps what I'm looking at doing is just cosmetic.

      I didn't commission this build, just bought it a year after construction finished and we are the second owners. I seems to me a certain design was picked and modified for improved sound insulation after the fact

      • They could have just gone over the prior existing facade to neaten it up, add another sheet layer over battens and render it to hide any damage/cracks/etc… If you're not 100% sure its for acoustic reasons.

        Even as you have somewhat deep eaves (in the photo) sarking is for condensation within the wall as much as any rain etc. so don't assume you're all good just from rain.

        Those little mounds of sawdust/sand you'd want to sweep away.

  • Termites will love the wood…. Get a proper building inspection to see what elese is wrong as you do NOT normaly sell a house after just one year.

    • Pests and humidity was my concern but the building and pest revealed no serious issues. We've already bought the place.

      We've got a builder coming in to do a few jobs for us. When he quoted us for the other things I showed him this but he didn't seem to indicate it was necessary, more just cosmetic.

      Was looking for a second opinion. The general advise so far seems to be that if I cover it up, to ensure I don't allow for water to pool around. I might just see if the wood can be coated with some water resistant material. As far as termites go, the whole building is treated and has had proper termite treatment applied so hopefully shouldnt be an issue.

  • I wouldn't cover it. Covering it will allow water to sit there and rot. Water needs to move and drain.

    It doesn't look like a neat detail at all. If you paid for that construction get it check out.

    If you bought it as existing then you might not have any other option.

    • Thanks for the input. Agree that I want to avoid water damage at all costs so I'm getting someone to have a look at it. It looks bad in photos from up close but from a normal standing person point of view, it really isn't that striking.

  • Be aware the ground around there will move up and down, putting anything hard against the concrete paving and the cladding will result in either the cladding being pushed up and cracking or being pulled down if you nail or glue it.

    I don't think there is anything in the building codes that cover this, as this would be deemed an alternative solution. It's not a perfect science.

    Where do you live? This definitely doesn't seem like NSW or VIC.

    • Thanks for the advice. I hadn't thought about potential movement. I have a carpenter coming for a few odd jobs in a few weeks and he said he'll take a closer look but initially he didn't seem to think it was an issue. I'm in QLD. To be fair, the photos make it look a lot worse than it really is. The house does appear to be raised off the ground but it isn't really an eyesore in any way from a normal standing point of view.

      As Thiefsie noted above, upon closer inspection I think the house is that way because it was double cladded on top of original plans. In some areas, on close inspection you can see that there are kind of two frames, one of which is flush to the slab edge and covered in a blue material, the other is installed on top, probably for insulation and acoustic reasons. It appears the walls are about 20cm-ish thick all around the house on the outside walls.

  • I can’t see a major issue with this, although not entirely sure what the build up of your wall is. Exposed timber would susceptible to rot over a long period, especially in Queensland where you get lots of heavy rain and it would no doubt cause that exposed timber to get wet frequently. I recommend protecting the timber with either good quality exterior paint or aluminium strip. Don’t cover the edge of your concrete up, needed to inspect for termites.