Browse Forums General Discussion Re: Chemical underpinning and soil stabilization 36May 11, 2019 9:43 pm Hi. Thought I would jump on this one too as I am currently looking at buying a place in Hobart that has had Mainmark's Teretek system used on it. The house is a 1983 build brick veneer on brick foundations on a predominantly plastic clay soil (undifferentiated alluvial). Apparently the vendor spent $60 grand on work to repair (plan of works attached) but another structural engineer didn't think it was going to do the job. Not sure if him missing out on the job two years ago to Mainmark is a contributing factor to his view though but he recommended a different method and in his view the drainage was the contributing factor to the shifting. Mainmark however didn't think it was and no drainage works were performed. I'm getting a geotechnical engineer to inspect the property next week as my main concern is finding out why it happened in the first place. I think drainage is an issue and a perimeter wall in the backyard is cracked and on the verge of collapsing due to suspected pooling of water, plus what the other structural engineer said. The house looks good now and you can see where the Teretek has done its job, however I am worried that further seepage underneath the resin injection sites (I'm not sure how deep they go down) will result in further shifting and won't be covered by the 50 year guarantee as it won't be a failure caused by disintegration or shrinkage of the resin. I'd appreciate any thoughts, especially on the amount that was spent, drainage and any interactions with Mainmark. Thanks! Jono Like ⋅ 1 comment ⋅ Pin to Ideaboard ⋅ Re: Chemical underpinning and soil stabilization 37May 13, 2019 2:52 pm jono85 The house looks good now and you can see where the Teretek has done its job, however I am worried that further seepage underneath the resin injection sites (I'm not sure how deep they go down) will result in further shifting and won't be covered by the 50 year guarantee as it won't be a failure caused by disintegration or shrinkage of the resin. Interesting to see the before and after numbers. Around bedrooms seems to have the better improvement than the other areas. I've just calculate the average and it seems be around 46% improvement overall Do you know what exactly is in the 50 year guarantee? and how do they measure that? It might be just saying the resin exists in the soil but really referring to any shrinkage or subsides in the structure! Can I ask how roughly how many meters of wall was covered in Teretek project? from my understanding they drill a hole every 60 centimeter or so. Re: Chemical underpinning and soil stabilization 38May 13, 2019 4:10 pm The guarantee covers any further shifting due to the failure or shrinkage of the resin which is why I was concerned about further shifting underneath the resin injection sites. Not sure how they measure it. Not sure how many metres of wall but the house area is approximately 200 square metres. For $60 thousand I'd expect they drilled quite a few! Re: Chemical underpinning and soil stabilization 39May 13, 2019 4:21 pm Resin injection is one of the most cost effective underpinning methods so 60k if it is true means there must have been major major issues. They can guarantee the product but can the guarantee the soil around the injected product.So if the initial problem was settlement caused by tree drying and after the injection the tree keeps on drying the soil then settlement will continue.The original problem has to be stopped otherwise the resin injection is a temporary fix.I think the system is a very good solution to remedy settlement but once the cause of settlement is identified and removed. Re: Chemical underpinning and soil stabilization 40May 15, 2019 6:47 pm Had a geotechnical engineer look at the place yesterday who has recommended some drainage options. I found that an internal door didn’t close properly and there was a 1-2mm going up from the top-right of the door arch. Mainmark said that it inlay be the footing underneath sinking as they only did the perimeter of the building. Doesn’t fill me with a great deal of confidence! Perimeter may be fine but what about the internal foundations? Hi Building Expert, Thank you for the feedback, much appreciated, there is also a code of conduct for building surveyors which they need to follow as well. I am looking… 4 3680 I am not sure whether Perth has its own way of doing things in regards to this. Most of Perth has class A (sandy soil), except for some areas near rivers or hills. 2 13111 We were lucky in that our old house was so small (86 square metres) compared to the new house, they were able to take enough readings around the old backyard house before… 8 37160 |