Thread: Man cave digout

Radon is found in soils and rocks containing Uranium, Thorium and Radium. In the NE United States those areas that overlay granite have Radon hazards.

Originally Posted by rob streeper

Radon is found in soils and rocks containing Uranium, Thorium and Radium. In the NE United States those areas that overlay granite have Radon hazards.

Radon is also found in Mortal Kombat

I've looked into it, and radon levels are pretty low throughout Australia, particularly qld, so I'm not overly worried, but I'll make sure to keep good ventilation through the room anyway, as I want to avoid other issues with dust and mould too. If I do end up installing an XBox, I'll put a ban on Mortal Kombat. (His name is actually Raiden, but better safe than sorry.)

Arhhh i knew it was close, Raiden/Radon... close enough for me, lol

I am bloody impressed with what you have done to get to where you are now... a lot of back breaking work with just a tad bit of QLD summer heat

Awesome work

Originally Posted by surfdabbler

Thanks for the heads up. I've never heard of Radon as an issue here, but there aren't many basements here, so it wouldn't be. Houses are built slab on grade, and I'd be surprised if even one house in 100 has a sub-ground basement. I'll look into it anyway and ask some people.

I have an extractor fan in the ceiling to get the dust out, and I will often open the door to get cross-flow through the room when I am working. Depending on how the humidity goes long-term, I may need some extra ventilation anyway, so I'll keep the radon issue in mind.

have a look here ARPANSA - Radon Exposure and Health

I suspect that controlling wood working dust will be a more pressing issue.
Working in a basement presents a real risk of filling the house with very fine dust. BobL's dust thread will get you started in managing that dust.

https://en.wikipedia.org/wiki/Radiation_hormesis

Originally Posted by rwbuild

Im doing a job at the moment that is 120+ yrs old, solid walls (no cavities external and 230mm thick internals) floor 200mm under joists to ground, no cross flow ventilation because vents are level with face of joists. Replaced floor joists with 100x50x2 RHS, termifloor sheet flooring and water proofed on bottom side before screwing to joists. Put in 6 pvc pipes directed to the dead air areas under the floor, made a manifold box and plenum wall, fitting solar powered fan in roof mounted to manifold and force feed the warm/hot air from the roof down under the floor, opened up air flow openings in all internal sub floor walls and added 10 new external vents to external walls.

Solar Whiz Roof Ventilation | Solar Whirlybirds | Commercial Exhaust Fans

Sounds like you're working on my house. Exactly the same criteria!

Looking good. How are you going to finish the walls?
It will look a bit brighter with a splash of white paint on the walls and ceiling.

Originally Posted by surfdabbler

I've looked into it, and radon levels are pretty low throughout Australia, particularly qld, so I'm not overly worried, but I'll make sure to keep good ventilation through the room anyway, as I want to avoid other issues with dust and mould too.

The fine print in the links I found suggests that one reason radon levels are low in Australian houses is that most Australian houses are very porous and very few have a basement. While not at a level that should be a matter for concern, the higher levels reported for parts of Sydney seems to correlate with those suburbs with a preponderance of older double brick housing.

Originally Posted by ian

The fine print in the links I found suggests that one reason radon levels are low in Australian houses is that most Australian houses are very porous and very few have a basement. While not at a level that should be a matter for concern, the higher levels reported for parts of Sydney seems to correlate with those suburbs with a preponderance of older double brick housing.

Per the Australian Radiation Protection & Nuclear Safety Agency (ARPNSA) Radon Map, average indoor radon concentration in Brisbane is <10 Bq/m3 against a recommended limit of 200 Bq/m3.

The US EPA's 'Citizen's Guide to Radon' recommended safe limit is 4 pCi/L (imperial units; converts to 148 Bq/m3) and many US homes apparently record radon concentrations above that limit.

It's really not an issue in Australia because of our geology - we generally have far less uranium in the coastal areas where our cities are located than the US does in their soil. It also no doubt helps that Australian houses are generally well ventilated for much of the year due to our climate, so just make sure you have good ventilation in your man cave and call it a day. No need for any concern.

In depends where you are in Australia. On the Perth Coastal plain the levels are quite low but in some areas of the Perth hills the laterite does concentrate uranium and hence radon. The overall background radiation in the Perth hills turns out to be ~5x that of the coastal plain. Houses built on top of ancient (i.e. buried) salt pans in the WA wheat belt and Yilgarn areas can also have higher radon content, definitely high enough to warrant proper ventilation for semi-sealed basements, but I doubt of any houses that have basements and they certainly well ventilate their houses in these areas.

Even mediocre wood dust ventilation will be enough to vent any radon.

Originally Posted by Moph

Per the Australian Radiation Protection & Nuclear Safety Agency (ARPNSA) Radon Map, average indoor radon concentration in Brisbane is <10 Bq/m3 against a recommended limit of 200 Bq/m3.

The US EPA's 'Citizen's Guide to Radon' recommended safe limit is 4 pCi/L (imperial units; converts to 148 Bq/m3) and many US homes apparently record radon concentrations above that limit.

It's really not an issue in Australia because of our geology - we generally have far less uranium in the coastal areas where our cities are located than the US does in their soil. It also no doubt helps that Australian houses are generally well ventilated for much of the year due to our climate, so just make sure you have good ventilation in your man cave and call it a day. No need for any concern.

I've just read a news article that would support the good ventilation hypothesis. Apparently homes in Calgary constructed in the past 25 years have higher radon levels than older homes. The only apparent difference being newer houses are better sealed and thus it's harder for the radon to escape.

I suspect there's a degree of complacency in Australia related to the absence of basements and the fact that the typical Australian home is very poorly insulated (and therefore very porous) compared to a North American home.

I've done some work on the concrete floor finishing this week. I put down a penetrating sealer, and then a contractor called Debbie came in and put a 300mm thick self-levelling compound on the floor. It has a beautiful gloss finish, despite the colour, which I call "Fresh Silt". Strangely enough, even though the finish itself is 300mm thick, it hasn't affected the head-height at all. Being a completely wet finish, you can just wade through it.

IMAG1423.jpg

Yep, cyclone Debbie did the man-cave. Overnight and through the morning, a small amount of water was still getting through the concrete walls, but nothing I couldn't sort out in a couple of minutes with the wet-dry vac. Then while I was out, my wife went down to check and found this. The sump pump had jammed on a rock, and the pit outside backed up. The very corner of the wall where it meets the existing structure was not waterproof enough to keep it all out, and it ran back into the man cave. Curse those pumps! This was the main reason I didn't want an internal pump like a french drain system. I've got the pump running again, but I can't fix anything properly until we get some drier weather, and that could take a while. I will have to take some of the drainage completely apart and rebuild it, as well as line the sump pit with something to make it waterproof right up to ground level, with a surface overflow drainage channel.

Meantime, I just have to baby sit it, and turn on the pump inside the room whenever needed.

If those walls are sitting on the slab the only sure way to stop the water weeping between the wall and the slab it to keep the water below the top of the slab. I had a huge issue with the same problem and three attempts later it seems to be resolved. I used two lots of so called water proofing which slowed it down when applied to the internal walls and down onto the slab and the final thing that stopped it was several coats of Ormonoid.