Humidity in enclosed porch...

[cuinohio]

We are currently in process of building our hot tub “room”.  We are enclosing a 8x24 porch…added four 4x2 awning windows, one 4x6 window (two doublehung) and one 6x8 french door.  We plan to open all windows when we are in the tub.  I think we are going with cedar paneling for the walls (1 wall is brick), ceiling is vinyl siding.  The new room shares the hip roof with the house so attic is above ceiling.  This is where the concern is….does anyone know how much humidity will be produced from the 325 gal tub at say 102 degrees?  Is there a formula for this?  Not sure what kind of exhaust fan to buy and if one is actually needed. P.s. No HVAC exists in this room.  Advice or links to where I can find info is greatly appreciated.

[Snowbird]

We have our J385 (550 gal) tub in a 12x18 room with 2 4x8 sliding windows and a 6ft sliding door.  There is no attic, but the roof is pretty high: 9 1/2 ft down to 7 ft.  Walls and stippled ceiling are green board sheetrock with 2 coats primer and 3 coats exterior semi-gloss latex.  Floor is Congoleum Ultima linoleum for easy mop-up.

I had no idea about moisture, so we planned for the worst.  I installed an exhaust fan that will clear the room 8 times an hour controlled by a humidistat.  Even if we are away, the room will stay at 70% humidity or less.  The room has sliding glass doors that go into the family room and the dining room so the fan draws dry air from the house.  In the winter, we turhn the fan off so it puts some humidity in the house to balance the gas furnace.

We've had the set up for a year and the fan is overkill, but we are often gone for 10 days or more so it is insurance more than anything  else.  Opening the windows solves dampness imediately.

I was concerned about water slopping out of the tub, but it just doesn't happen.  What little water drips from the cover is absorbed in an old sheet we lay on floor under it.

The winter is great tub weather.  About 10 minutes before soaking we open the qwindows and slider and we get all the benefits of an outdor tub and none of the negatives.  We are high so no one looks down into our room.

[cuinohio]

Thanks for the reply snowbird, so does your fan run a lot?  What brand did you purchase?  I would assume the tub would not generate humidity with the cover on, right?

[nicker]

I can not comment on the fan.  But one thing to consider if you haven't.  Are you putthing the tub in and enclosing it?  Or adding it later.  Just make sure you have a good way to get the tub out if needed with out demolshing walls etc.

Freind of my enclosed his tub and then ran into a problem and they had to replace his tub.  He endedup having to creat a large exit door after the fact.  It would be easier to think of that when building and designing your encloser.

Just a thought.

[East_TX_Spa]

I sure do like that valance Snowbird, it still do look good!

I've kept two spas in our moodroom for almost 4 years now.  There is no ventilation except for an AC vent.  I've never seen any evidence of mold, mildew, or moisture damage.  The spas are even open most of the day.  It's a small room.

I just don't think its that big of a deal, but I am in Texas, and Texas is just better than most places.

Terminator

[The_Pa._Lady]

We have our 325 Gal. HS Prodigy on our patio.  It is sort of enclosed, we have screening with 2 screen doors, but no windows.  When we use the tub at night you can see the steam going out through the screen.  The ceiling is aluminum, and the floor concrete.  I like the idea of using an old sheet to catch the water that drops from the cover, I never thought of doing that.  Yes, I know that the water would not hurt the floor, but I worry about my puppy drinking that water, so I keep him indoors when we are in the tub.  

Good luck with your venture, it looks good!  What make is your tub?

[ZzTop]

Depending where you live humidity can be a real problem.

You have a really nice decorated room and you sure would not want it to suffer from mold and mildew problems.

Depending where you live humidity can be a real problem. You might want to consider a Humidistat and fan combination.  The fan will automatically come on when the humidity reaches a preset threashold.


I hope you have made sure the floor under your tub is adequately supported as it represents a lot of weight, in the order of 4000 to 5000 lbs.

Regards, Zz

[cuinohio]

Thanks for all input.  We are either getting a HS Prodigy or Jettsetter.  Both will fit thru the French door.  Floor is concrete slab...we will probably tile over it.  We live in NE Ohio so outside humidity is only a problem for a few months.  I really don't want to put a hole in the roof (for the exhaust fan) if we don't need it...trying to decide now while we are in the remodelling stage.  The windows are big so I was hoping the humidity would leave the room via the windows.  Also, I am told that cedar (wall covering)  is moisture tolerant... hope that is true.  PA Lady, do you notice a lot of moisture buildup on your ceiling?

[The_Pa._Lady]

cuinohio,

to answer your question regarding moisture buildup on ceiling, yes, we do get some but it goes away rather quickly.  In our case it is no big issue because there is nothing to damage being that we have a brick wall and screening on the other 3 sides. It does not form any drops. The moisture is no worse than when it rains and the humidity is high.  We here in Pa. always have humidity to deal with.  

Good luck on chosing your hot tub.  Like I said in my previous post, we really love our Prodigy.  We've had it since July, and recently did a water change, all went well.  We use it daily.  

[tileman]

Just TILE the whole room from floor to ceiling.

[Tubaholic]

I also have an indoor hot tub (HS Grande) and moisture was a big concern for us also.  We have 5 sliding patio doors and 4 skylights  above the tub that open. The floor is tile and we lay a towle down so the water that drips from the cover  never even gets the floor wet. Also incorporated into this room is a wood stove and that does a wonderful job of wicking away moisture on the nights its just to cold  up here in the Chicago burbs to keep the windows open. We are able to close this room off from the rest of the house and HVAC system so no additional moisture enters into the main part of the home. After several years I am happy to report never having any problems at all and we love have the tub indoors. Click on my name for a larger photo of the tub room.

[tileman]

I also have an indoor hot tub (HS Grande) and moisture was a big concern for us also.  We have 5 sliding patio doors and 4 skylights  above the tub that open. The floor is tile and we lay a towle down so the water that drips from the cover  never even gets the floor wet. Also incorporated into this room is a wood stove and that does a wonderful job of wicking away moisture on the nights its just to cold  up here in the Chicago burbs to keep the windows open. We are able to close this room off from the rest of the house and HVAC system so no additional moisture enters into the main part of the home. After several years I am happy to report never having any problems at all and we love have the tub indoors. Click on my name for a larger photo of the tub room.

All I have to say is BEAUTIFUL.

[hot tub Frank]

i do like that setup

[anne]

Tubaholic has one of the nicest set-ups I have seen, indoors or out. I LOVE the knotty pine, the skylights, the big windows.......

[Slappy]

I have to agree with you anne. One of the hottest tub rooms I've seen.