Browse Forums Paving & Concreting Re: Slab Quality - Advice Needed Please! 2Nov 04, 2014 9:45 pm The Honeycombing is caused by inadequate vibration of the concrete to remove all the air that gets trapped in the wet concrete. Typically it is worse at the edges of slabs as the concrete, when placed, gets pushed towards the edge forms again trapping more air. If it is just on the surface its not a big an issue as if its extends further into the slab Typically the concrete like this has less than 50% of the strength of dense concrete. Really the only way to check further is to drill cores through the slab and get an engineer to sign off Either its OK, or determine the actions needed to ensure you finish up with a serviceable slab. I would suggest you send these photographs to the Manager of the Builders with a letter expressing your concern. The Harder You Try - the Luckier You Get ! Web site http://www.anewhouse.com.au Informative, Amusing, and Opinionated Blog - Over 600 posts on all aspects of building a new house. Re: Slab Quality - Advice Needed Please! 3Nov 04, 2014 11:05 pm This is simply poor workmanship but you won't know how bad it is unless, like Bashworth suggested, you get your builder to investigate. Re: Slab Quality - Advice Needed Please! 4Nov 04, 2014 11:53 pm According to a concreter who has seen this picture, he believes concrete has been poured on top of older concrete that has already gone off. What you can see as honeycombing, is this layering. This could be bad service by the concrete plant, as the concreter was very likely kept waiting for the next load. But they should have used a concrete vibrator (normal practice) to bond the older concrete with the newer load, especially on the edges of slab and footings. The concreter might have run out of time due to poor service (which is quite common) by the concrete plant and drivers. They can often make or break a job. Structurally, he says it needs to be "parged" on the edges. It is fine for a single storey, but he would be concerned if the house is double storey.... Re: Slab Quality - Advice Needed Please! 6Nov 05, 2014 6:29 pm I would be interested if you could pass on what your building inspector says. I think it is a great idea to get it checked Re: Slab Quality - Advice Needed Please! 10Nov 05, 2014 8:13 pm A cold joint is where one batch of concrete is starting to cure before the next batch is poured. In Brisbane at the moment its common for big delays between loads. My advise is to bypass the building inspector and request the builder has the engineer look at it. Yes its ugly, but ugly doesn't mean its defective. Thats something the engineer will need to determine. Re: Slab Quality - Advice Needed Please! 12Nov 05, 2014 8:44 pm I would ask why a concrete vibrator wasn't used to bond the two layers together... Re: Slab Quality - Advice Needed Please! 14Nov 07, 2014 4:53 am If they are proceeding with the frame, it is sounding like you will likely be brushed off. Your only option at this stage is to instruct you bank to not pay the slab claim. This will be your only leverage against the builder. Only release the payment once you are satisfied with the outcome. It would be prudent to get on the front foot and email the building manager and advise him, with the photos, that you are not paying this stage claim. Please keep up informed of how it progresses Re: Slab Quality - Advice Needed Please! 15Nov 08, 2014 11:43 pm These type of site supervisors should be renamed Iraki ministers of propaganda,you will not get even close to a true opinion if you don't get a good independent inspector or engineer whom don't do any work for volume builders, I would make sure I,m there while its looked at, ask inspector what he would recommend if it were his family home,be firm and attack with knowledge, good luck Re: Slab Quality - Advice Needed Please! 16Nov 09, 2014 12:15 am Sometimes things look bad but are just superficial. There is no exposed mesh or anything. Unless you are told by someone who really knows what they are talking about that this is bad, don't panic yet. Re: Slab Quality - Advice Needed Please! 18Nov 09, 2014 7:22 pm Did they they talk about parging the edges? Re: Slab Quality - Advice Needed Please! 20Nov 09, 2014 8:21 pm Trust dad to look out for you. Yeah they can make up a slurry to go over it as a cosmetic job, but now that it's dry, it won't bond too well. Anyway, you'll have some sexy bricks going on soon that will take your mind and eyes off it. Hope it's all smooth sailing from here. Thanks for the insights, that makes perfect sense, and yeah, I will be leaning on the experience of the excavator operator entirely. 6 16147 4 6201 The concreter will take and reuse. In my case I bought structural LVLs and scraped them back and used them as joists. 1 5159 |