Browse Forums Building A New House 1 Jul 29, 2015 12:04 pm We’re coming up to our 90-day maintenance period with Wisdom and I’ve noticed that the shower in our Master Ensuite doesn’t have enough fall to drain the water away from the furthest point from the drain (the shower is 2.1m by about .9). It has a strip drain towards one end (where the main shower head is) so the fall should be towards that. It seems to dry fine so far but I’m wondering what future problems could arise from this? Reason I’m asking is I imagine the fix will mean ripping up the tiles which is going to be a PITA for us while they do it so hoping to avoid that if possible. Re: Insufficient fall to shower – what problems could this c 2Jul 29, 2015 12:39 pm Hi Matt1 Is it just wet, ponding and not draining and how much water are you talking about...photos will help? Designer,Engineer (Civil,Const & Envir),Builder,Concrete & Masonry Contract.Struct Repairs Re: Insufficient fall to shower – what problems could this c 3Jul 29, 2015 1:19 pm It doesn't seem like a lot. I'll take a pic when I get home. Re: Insufficient fall to shower – what problems could this c 4Jul 29, 2015 2:39 pm It should all be sealed so I doubt you'd get problems outside the room; however if the room doesn't dry due to water pooling, then it might mean you'll get mould in future. If it's drying fine in winter & you don't want the PITA-eyness of getting it fixed, I can't think of other problems ... ? Re: Insufficient fall to shower – what problems could this c 5Jul 29, 2015 3:56 pm Shower should not hold water. If its leaking at outlet and you are on reactive soil you could be having foundation heave. Have it professionally checked Foremost Building Expert in Australia,assisting with building problems/disputes, building stage inspections,pre-contract review advice for peace of mind 200 blogs http://www.buildingexpert.net.au/blog Re: Insufficient fall to shower – what problems could this c 6Jul 30, 2015 12:29 am Here's a pic, 12 hours after it was last used. http://i569.photobucket.com/albums/ss136/matthewmedlin/2015-07/7A2A4E2D-18AA-402F-A824-C06AF1269373_zpsyos1bwgw.jpg It's a 1st floor bathroom too. Re: Insufficient fall to shower – what problems could this c 7Jul 30, 2015 7:38 am Shower should have 1:80 fall to the drain Re: Insufficient fall to shower – what problems could this c 8Jul 30, 2015 12:34 pm Excuse me for chipping in here. wood bang Shower should have 1:80 fall to the drain Woodbang, is there a regulation that states this? We have the same situation as above in our shower but I notice the designer has the following instruction in the notes: Set down RC slab in front bathroom by 50mm to allow for adequate floor fall. Re: Insufficient fall to shower – what problems could this c 9Jul 30, 2015 3:41 pm Liliana Excuse me for chipping in here. wood bang Shower should have 1:80 fall to the drain Woodbang, is there a regulation that states this? We have the same situation as above in our shower but I notice the designer has the following instruction in the notes: Set down RC slab in front bathroom by 50mm to allow for adequate floor fall. Yes, AS 3740-2004 Clause 5.9 and appendix C Fall needs to be between 1:60 - 1:80 Re: Insufficient fall to shower – what problems could this c 10Jul 30, 2015 8:19 pm Thanks wood bang, I've found it. For some reason AS 3740-2004 is freely available on the web here: http://supersealindustries.com.au/seald ... as3740.pdf Is this standard referenced in the BCA/NCC? Also looking at Appendix C3 Fall Ratios - it certainly says "the recommended ratio of fall within a shower area is between 1:60 and 1:80" but is "recommended" the same as "mandatory"? Not trying to be smart, just wondering whether a client would have a case for rectifying the fall if is only a recommendation? Re: Insufficient fall to shower – what problems could this c 11Jul 31, 2015 8:19 am I've just found a PDF file on the web which discusses falls in floor finishes and AS 3740. You can find it at: http://www.atcnsw.com.au/download/Falls ... C-2011.doc It defines how fall is measured: How is fall measured? While it is sometimes referred to in “degrees” and sometimes as a certain measurement over a certain distance, most construction specifiers stipulate it as a ratio. For example 1:100 means for every 100 units along a floor, the floor should fall by 1 unit, 1:60 is steeper as the floor would fall 1 unit in only 60 units, and a 1:1 ratio would be a 45° angle. [1:100 is 10mm per lm, while 1:60 is 16.6mm per lm and 1:50 is 20mm per lm.] States the standing of AS 3740: AS 3740 “Waterproofing of wet areas within residential buildings” is a “deemed to comply” standard, and it is called up as a method of meeting the “performance requirements” of the Building Code of Australia (BCA). This standard calls for falls in showers to be between 1:60 and 1:80 and not less than 1:100 in areas outside the shower in its appendix B, and the BCA 2008 reproduces the appendix almost word for word as clause 3.8.1.14 “Falls in shower floors”. It says: The entire shower area must be constructed so that water flows to the waste without ponding. Offers a definition of ponding because: Unfortunately, neither the BCA nor AS3740 provide a definition of ponding. The committee decided against defining “ponding” as it thought that there were too many variables to allow for a valid Australia wide definition. Some of the variables are; the relative humidity, exposure to the elements, the grout joint width, the surface type of the tile, whether it is sealed or unsealed tiling, surface texture and surface tension. It also says that aesthetics and safety play a role in deciding fall: The amount of fall achieved is sometimes affected because of aesthetic and safety concerns. For example, if the floor waste in a bathroom or laundry was 2.5 metres from the door, and a 1:100 fall was installed, the door strip would have to be 25mm higher than the waste. If the concrete substrate was level, and there was a minimum 30mm depth for tile and bed at the waste, the finished height at the doorway would be about 55mm. This would usually be considered an unacceptably high threshold, so less fall is accepted. Re: Insufficient fall to shower – what problems could this c 12Jul 31, 2015 8:58 am Quote: It also says that aesthetics and safety play a role in deciding fall: The amount of fall achieved is sometimes affected because of aesthetic and safety concerns. For example, if the floor waste in a bathroom or laundry was 2.5 metres from the door, and a 1:100 fall was installed, the door strip would have to be 25mm higher than the waste. If the concrete substrate was level, and there was a minimum 30mm depth for tile and bed at the waste, the finished height at the doorway would be about 55mm. This would usually be considered an unacceptably high threshold, so less fall is accepted. While I agree with this somewhat, at the stage of the slab being poured there is no reason for not having a stepdown in the concrete to allow for this. If all the floor finishes have been chosen - tiles to wet areas, carpet to bedrooms and study, timber floor to traffic areas and family rooms etc , then there should be no difference in height to any transition point between these surfaces. Whether the builder wants to or is capable of doing this is another story. Stewie Thank you Splashers. Tomorrow I might check if I can get a few packs of 300x300 in the same tile finish. It may be good to use these could in the shower recesses. I'm not… 4 4682 1 6625 Firstly the ableflex that has been installed needs (manufactures specification) a sealant cap over the top, preventing water draining down between the slab and the… 3 7776 |