pressure balanced vs thermostatic valves (1/2 inch vs 3/4 inch)

Discussion in 'Shower & bathtub Forum & Blog' started by Shawn_T, Jan 19, 2012.

  1. Shawn_T

    Shawn_T New Member

    Messages:
    17
    Location:
    Vancouver, BC
    I am in the process of installing a shower which will have a rain showerhead, a hand shower unit, and 2 body sprays. I would like to be able to use the body sprays at the same time as the rain showerhead, and then be able to use all 3 components by themselves. I have 3/4 inch plumbing run from the main water line. I am thinking that it would be best to use the 3/4 inch plumbing to feed a 3 way diverter valve and then feed 3/4 inch into a transfer valve which feeds 1/2 inch plumbing to the showerhead, handshower and body sprays. I was thinking about using a 6 function, 3 port diverter for this setup but it seems to be very difficult to find the correct valves and trim for this. Is there a better way that I should be looking at configuring this? Should I step the 3/4 inch plumbing down to 1/2 inch with a bushing right before the diverter? Would there be a noticeable reduction in pressure by doing it this way? Because I have 3/4 inch plumbing I wanted to use it to feed the valves, but it may not be feasible. Would it be better to use pressure balanced and diverters, or thermostatic with volume controls? Any help is appreciated very much. Thank you.
  2. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Messages:
    21,814
    Location:
    New England
    FIrst thing, add up the specs on the volume each thing uses, add up any/all that you want to be able to run at once. Then, compare that max value to the max flow capabilities of the 1/2" and the 3/4" valves. If the 1/2" valve can handle the flow volume (probably not), go with it as it's cheaper. You'll probably end up with the 3/4" valve which can , depending on the design, often more than twice the flow of the same company's 1/2" valve. You shouldn't make assumptions, you need to read the specsheets as there is quite a variation between both brands and lines within a brand.

    Personally, I like to be able to set the temperature and never adjust it. This is more reliable with a thermostatically controlled valve summer/winter, full tank/near empty than a pressure balanced valve which doesn't take into account variations in cold or hot water supply temperatures - that's all up to you.

    As to how best to select a diverter and plumb it, can't help you there.
  3. Hackney plumbing

    Hackney plumbing Homeowner

    Messages:
    1,174
    Location:
    Alabama
    What thermostatic shower valve do you have? My next shower will be thermostatic and piped with independent positve cut off volume controls for each function. Rain showerhead,handshower,wall showerhead and 6 body sprays. Same thing on the other side of the shower including another rain head. Two 3" shower drains. max flow would be close to 35 gal a minute.

    Each set of 2 body sprays would have its own positive cut off volume control valve,allowing you to turn them on or off in combinations of two's for a total of 6.
    Last edited: Jan 19, 2012
  4. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Messages:
    21,814
    Location:
    New England
    In my last trip to London, the hotel I stayed in had Grohe thermostatically controlled valves...the pressure was bouncing all over the place, but the temp stayed nice and consistent. So, when I remodeled, I decided to use one of theirs. I do not have any experience with others, and I'm sure other brands make some that work well, too. Mine is a weird one as it has a built-in diverter for a shower (via a hose connection), a tub spout, and the temp and volume controls all in an external mount fixture - the thing weighs about 10#. There is an air duct immediately behind this wet wall, and I wanted something that could be serviced easily without dealing with it or the granite tile on the wall. Then, throw in a pocket door, and access after the fact is almost nonexistent.
    Last edited: Jan 19, 2012
  5. johnfrwhipple

    johnfrwhipple I love these ACO Shower Drains - Best in Class

    Messages:
    3,810
    Location:
    North Vancouver, BC
    What type of hot water tank do you have?

    Is your 3/4" lines run in copper or pex?

    What size is your drain?

    What is the flow rate of your fixtures? Most are 2.5 gallons per minute but many people have their restrictors removed when installed.

    If you like long showers you might consider one of these heat recovery systems the men have been talking about lately.

    If you like lots of pressure you should make sure your shower drain is a high flow capicity like a linear drain or 3" point drain.


    3/4" is ideal and will supply your valve with all the water it can handle. From there some proper layout is needed for an even balance.

    Where do you want your body jets to hit your body? Where is your glass going?

    Why not post a room layout and your wish list.

    The more information you can provide the better advice you will get here.

    JW
  6. Shawn_T

    Shawn_T New Member

    Messages:
    17
    Location:
    Vancouver, BC
    I have a tankless hot water heater so losing hot water is not an issue.
    The 3/4 lines are pex.
    The drain is 3".
    Each fixture will most likely be 2.5 gpm. I haven't bought them yet but everything I have looked at has been 2.5 gpm.

    The one thing I am not sure about is whether I want to use a pressure balanced system with diverters, or thermostatic system with volume controls? Any advice on this would help make my decision easier. Thank you.
  7. Hackney plumbing

    Hackney plumbing Homeowner

    Messages:
    1,174
    Location:
    Alabama
    I'd used a thermostatic valve and independent positive shut off volume controls for each function or group of functions.
  8. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Messages:
    21,814
    Location:
    New England
    Some thermostatically controlled valves want shutoffs before them, some can use them after them, so depending on the control you select, make sure it can work the way you want.

    Note that 3/4" pex has a smaller ID than copper, and bigger than 1/2" copper, it's still not the same as 3/4" copper and you will likely see a lowered volume than you would with copper...you probably won't see the full volume available if you had copper there, so keep that in mind when selecting the devices you wish to use. As long as the pipe can deliver more than you're using, you should maintain pressure, but try to use more, and it will drop, maybe to a value that would degrade your pleasure and expectations.
  9. johnfrwhipple

    johnfrwhipple I love these ACO Shower Drains - Best in Class

    Messages:
    3,810
    Location:
    North Vancouver, BC

    I like the thermostatic control feature and individual control valves.

    A 3" drain is great if your working with some large water volume.

    Often my clients complain about water pressure. If your expecting big things from your new fixtures you might be a little disappointed. Lately we are dealing with clients removing the restrictors so size the drain and flow rates to handle this if you should happen to ask the plumber to remove them.

    What make of fixtures?

    [​IMG]

    [​IMG]

    [​IMG]

    [​IMG]

    This DornBracht line is outstanding if it's in the budget!


    Any steam?

    JW
    Last edited: Jan 22, 2012
  10. Shawn_T

    Shawn_T New Member

    Messages:
    17
    Location:
    Vancouver, BC
    Thanks for the info. I am currently looking at the following lines:

    Kohler Purist
    Brizo Euro
    Delta Arzo

    Is there one that is recommended over another, or one that I should stay away from?
    I have not heard of Dornbracht before but they do look very nice. I will look into their prices.
    I do have a Relax-a-mist steam generator that will be installed.
  11. johnfrwhipple

    johnfrwhipple I love these ACO Shower Drains - Best in Class

    Messages:
    3,810
    Location:
    North Vancouver, BC
    The relax a mist generators have two steam outlets so plan your fixtures and benches away from these. Often you see them grouped somewhat close together.

    The Dornbracht fixtures tie into steam shower waterproofing wonderfully as do many others.

    Make sure your tile setter gets the proper water/vapour flashing details from the plumbing fixtures. These details so often get missed. Or the fixtures do not provide them.

    [​IMG]

    The Dornbracht features come with Kerdi Flashing details but Noble Seal TS ones are easy to make in replacement.

    [​IMG]

    Check with your plumbing retailer and ask which of your selection works best with a steam shower.

    [​IMG]

    Are you adding any lighting?

    JW
  12. Shawn_T

    Shawn_T New Member

    Messages:
    17
    Location:
    Vancouver, BC
    Thanks for the tip about the water/vapour flashing. I had not thought about that yet. Does it make sense that I will be using hardie tile backer, mesh tape in the corners, thinset in the seams and then a rubber compund rolled over everything? Am I missing anything?

    I am not planning on adding lighting because there already will be adequate lighting in the room.

    I have just received a quote for American Standard (Boulevard line) that includes a 3/4 inch thermostatic valve and 3 - 3/4" volume controls. The quote for this system is about $450 less than the same quote for the Brizo (Euro line). Do you think I will be satisfied with the performance and the durability of the American Standard Boulevard product line?

    I have not decided on the brand of body sprays that I want to use yet. I was thinking the Delta T1817 body spray looks good becuase it has 2 spray jets in one unit that are 5 inches apart. The unit runs at 2.4 gpm. This would hopefully give a satifactory width of spray so that I wouldn't need to go with 2 separate sprays beside each other. I may go with 3 of these body sprays because the rough-in valve (R530) can generate 16 gpm and this should be enough pressure to run the rainshowerhead (2.5 gpm) as well as 3 bodysprays (2.5 gpm each). Any thoughts? I am also considering the Moen TS1320 body sprays because they would match the showerhead I am planning on using. Any recommendations on a different body spray that has great performance without breaking the bank? The Dornbracht looks like it may be a little pricey.

    Here is a picture of the delta body spray I referred to: t1817.jpg
  13. Hackney plumbing

    Hackney plumbing Homeowner

    Messages:
    1,174
    Location:
    Alabama
    Dornbracht only promises to have replacement parts for like 10 years after a fixture is discontinued. IMO thats not acceptable. Buy the Delta.
  14. johnfrwhipple

    johnfrwhipple I love these ACO Shower Drains - Best in Class

    Messages:
    3,810
    Location:
    North Vancouver, BC

    For steam showers we like installing Noble Seal TS - you can use a liquid membrane like Hydro Ban or Red Guard but you need to follow the install spec's to a T. Kerdi works as well but choose a tile that is acceptable with non-modified thinset. The steamer above is my last Kerdi project.

    Steamers with liquid membranes on the walls need a poly behind your hardie lapping over your linear.

    Look up "Hydro Ban Steam Shower" online - they have a very good install description online.

    You can get hydro Ban at Centanni Tile in Burnaby - use my account if you like to get a better price. Tell Gloria John says it's OK. :)

    That said if you where my client I would be pushing for a sheet membrane like Noble Seal TS.

    Any exterior walls?

    Are you going for a sloped ceiling or flat? Sloped is the correct way but often hard to achieve and maintain some style at the same time.

    What are your ceiling heights?

    [​IMG]

    JW
    Last edited: Jan 24, 2012
  15. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Messages:
    21,814
    Location:
    New England
    A flat shower ceiling tends to drip all over onto you when you've got the steam up. Sloping it causes the condensation to mostly flow to the low side and flow down the wall rather than drip.
  16. Hackney plumbing

    Hackney plumbing Homeowner

    Messages:
    1,174
    Location:
    Alabama
    Riddle me this.....And seriously I really wouldn't believe it myself if it wasn't in my own shower. I have a 12 yr old home with a large walk in shower with two control valves and one drain. Its an odd shape but works out to be around 20 sq ft of floor space. The cultured marble walls extend about 82" from the floor. Now to the gravy.......the ceiling and the 12" or so of the exposed vertical wall is just green drywall that I painted. When I say I painted I mean I laid some paint on it..LOL. It has about 7 coats of oil base paint before the shower ever got wet. It gets steamed up but never mildews and it never peels.......it gets yellow streaks that cleans right off. So WTH are the yellow streaks? After I clean it off it takes a couple mounths for it to come back. Its not super bad but its enough for me to see and want to clean.
  17. johnfrwhipple

    johnfrwhipple I love these ACO Shower Drains - Best in Class

    Messages:
    3,810
    Location:
    North Vancouver, BC
    Built and used a lot of steam showers have you Jim?

    I have a small handful of clients here in Vancouver that would call BS on yah.

    Design or Function - often design wins out in the end.

    Most clients do not want the slope ceiling.

    Flat Ceiling Half glass half tile.

    [​IMG]

    Flat all the way

    [​IMG]

    Flat

    [​IMG]

    Flat

    [​IMG]



    JW
    Last edited: Jan 24, 2012
  18. Shawn_T

    Shawn_T New Member

    Messages:
    17
    Location:
    Vancouver, BC
    I will be sloping my ceiling and it is 8 feet high. There is one exterior wall on the side where the bench is with the pink insulation in the photo. The rain shower head and all 4 body sprays will be opposite the bench, with the handshower located just to the right. The two steam generator nozzles will be coming through the wall to the right of the bench. There will be a glass door to the left of the bench.

    I think I am going to use green e-board, mesh tape in the corners, thinset the seams, and then seal up with Laticrete Hydro Ban. I was thinking about Noble Seal TS but I think that will bring the cost up quite a bit and using Hydro Ban should be more than a sufficient seal as long as it is used properly. I am going to use a dry glaze porcelain tile (http://www.amestile.com/upload/pdf/CementiProductSheet.pdf).

    Also, I have also decided to go with the American Standard Boulevard line (3/4 inch valves) with 4 American Standard spray jets (1660130.002).

    Let me know if you can see any problem with this configuration. Thanks for your help.

    shower2.jpg

    It's gonna be nice to get this project moving forward again.
  19. johnfrwhipple

    johnfrwhipple I love these ACO Shower Drains - Best in Class

    Messages:
    3,810
    Location:
    North Vancouver, BC
    I would use cement board if your planning to use Hydro Ban.

    Green EBoard is a bio degradable board and not one I think you want seeing water vapour over and over again.

    Consider using a continuous thermal break on the exterior wall with perhaps some rigid insulation.

    You will need poly lapping over your studs and that linear.

    Re - read the Laticrete steamer specs and make sure you do it right.

    That linear needs to be extended up the wall. Then the poly over top.

    IS that bench sloped?

    Where in Vancouver are you?

    JW

    [video=youtube_share;-5Xr9YaSoWU]http://youtu.be/-5Xr9YaSoWU[/video]

    Or last steamer firing up.
  20. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Messages:
    21,814
    Location:
    New England
    I did say 'tend to drip', that doesn't mean it will, all things being equal.
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