Groundwork & Foundations Question

Raft foundation failing

Hi I have a end-of-garden block built annex on a raft foundation. There has been cracks appearing in the middle to the roofline and inside the coving has come away showing clear movement only to the front side of the annex. I'm guessing the raft foundation is failing as its not been dug deep enough to solid food. I may need under pinning but i need some advice as to cost and the only access i have is through the house, also to confirm if this is the case.

2 Answers

Not good maligolf, typically a raft foundation is used on land that can be suseptable to movement, hence the reason it is a raft, it is important that they are constructed in the correct manner and yours may not have been reinforced. If it were my prooperty i would find a structural surveyor to come and take a look and give you a report, this may be as much as £500 but at least you will get the exact solution and can work from there.

Good luck

Answered 26th Jan 2012

Local patios and driveways

Member since 24 Jan 2012

a raft is an independent foundation that is nebver very deep, usually used in high clay content ground, its strength is the steel reinforcement within the raft, its also ment to move as the clay exspands and contracs with water
retention and evaporation, this may cause small cracks without seeing it i cant help anymore id get a structural servey done locally then post as a job on here and find a local firm to give you a quote
good luck

Answered 26th Jan 2012


Member since 21 Nov 2011

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