Retrofitting radon sump

dublindaveae111

Hi all,

I am looking to put in a radon barrier and radon sump during a renovation. The void under the floor in 300mm with a concrete base. Just wondering should I chase out some of the floor to set the sump into it or sit it on the concrete and vent in it that way?

Any advice? thanks.

C. Eastwood

https://www.boards.ie/discussion/2058255055/retrofitting-radon-sump

First of all check on the link below with your Eircode to ascertain if a Radon Barrier is required for your area.

(Do not have a space in your Eircode)

https://gis.epa.ie/EPAMaps/Radon?lid=EPA:RadonMapforWorkplaces

Some areas do not require a Radon Barrier. The Radon Sump is always required for new works and in renovations, where practical.

Biker1

https://www.boards.ie/discussion/comment/119355475#Comment_119355475

Those radon maps are only indicative and a house in what appears to be a low radon area may have radon above the safe levels. The only sure way of knowing is to do a radon test.

C. Eastwood

https://www.boards.ie/discussion/comment/119355966#Comment_119355966

That’s a good idea

dublindaveae111

I'm in the yellow area, but just to be on the safe side I'm going to put in both the barrier and SUMP and while I've the floor up I might as well. Just unsure of how to fit the sump with the solid sub floor.

C. Eastwood

https://www.boards.ie/discussion/comment/119358995#Comment_119358995

Is the subfloor existing.

What are the heights of your proposed hardcore and concrete.

See Photos from Homebonds House Building Manual. Are these of any help.

5C78E90C-AF07-412E-A842-E39D865894B7.jpeg

AAA5E9D9-2959-4945-981F-F9D66BB6C5BE.jpeg

46CE8667-9FE8-4A69-8B3D-25233B65EA56.jpeg

dublindaveae111

They have good info thanks. As I have a concrete base I am going to go with the barrier ontop, spray insulation then underfloor heating and screed to bring me up to the existing floor level.

C. Eastwood

https://www.boards.ie/discussion/comment/119361887#Comment_119361887

I have never used spray insulation in a floor. Sheet insulation is far mor superior.

The underfloor heating pipes should be in a 50 mm screed, on top of the 100 / 150 mm insulation on top of the 150 mm Concrete subfloor.

See photos

AD8B12E2-F275-45DE-A746-B84492CDD28E.jpeg

0EFAD860-3CF3-4287-B6AA-E7959E99569A.jpeg

dublindaveae111

I'm using the TLA200 it's a mix of concrete and insulation. Will give them same Uvalue as PIR apparently. Yes it will be 50mm screed ontop I believe. I'm going to pull up the suspended floor now in a few weeks. Hoping the radon barrier isn't too tricky with the internal walls still in place

C. Eastwood

https://www.boards.ie/discussion/comment/119368848#Comment_119368848

Find the existing horizontal DPC in the existing walls, apply Premium Acrylic Sealant - radon sealing - on to the DPC and push the turn-up of the Radon Barrier DPM on to the Acrylic Sealant, and make sure it is bonded.