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Hi All,
I got a very high radon reading so will be adding a radon fan to a radon connection point outside our house. I just opened the connection point cap and saw that the connection point (and presumably all 4 sumps its connected to) are full of water - almost to the top! The sumps and radon barrier were installed a few years ago when replacing suspended floors with solid floor PIR insulation, UFH and screed.
The sumps and sump pipework sit on top of the slab and then have the new radon membrane over them and then a new concrete subfloor directly on top of membrane. (As an aside, I assume this is bad as the sumps are not in hardcore, so there is very little air which the fan can suck out, I think the sump should have been put under the slab in hardcore.)
I drilled a temporary little hole to let the water escape but it is now filling again at a few mm per day. Does this mean I have a leak? The house is well above the water table so don't think its ground water.
Love to hear anyone who has had similar experiences or thoughts on the cause and solution.
I got a very high radon reading so will be adding a radon fan to a radon connection point outside our house. I just opened the connection point cap and saw that the connection point (and presumably all 4 sumps its connected to) are full of water - almost to the top! The sumps and radon barrier were installed a few years ago when replacing suspended floors with solid floor PIR insulation, UFH and screed.
The sumps and sump pipework sit on top of the slab and then have the new radon membrane over them and then a new concrete subfloor directly on top of membrane. (As an aside, I assume this is bad as the sumps are not in hardcore, so there is very little air which the fan can suck out, I think the sump should have been put under the slab in hardcore.)
I drilled a temporary little hole to let the water escape but it is now filling again at a few mm per day. Does this mean I have a leak? The house is well above the water table so don't think its ground water.
Love to hear anyone who has had similar experiences or thoughts on the cause and solution.
