Making Progress - Ready for greenboard

[Snowbird]

Insulation is finished and the other window is in.  Still waiting to have the sliding glass door put in to the right out of the picture.

I need to put speaker wires in the walls and mounting boards for the TV and stereo arms and drapes.  After I put the heat/ac duct in, we will be ready for drywall.

The tub is covered for a little protection.  I put a support in the middle of the cover to allow us to walk on it so it pretty sturdy.

We are very concerned about the humidity in this room. There is a 6 inch exhaust vent high in a corner above the tub controlled by a humidistat on the other side of the room.  The fan can change the air 8 times an hour.  

Our big concern is mold on the floor when water splashes out.  We plan to sponge mop after each use. Any suggestions?    I would like to know if anyone else has a similar set up and how they deal with it.

[ssbraun]

We are very concerned about the humidity in this room. There is a 6 inch exhaust vent high in a corner above the tub controlled by a humidistat on the other side of the room.  The fan can change the air 8 times an hour.  

One thing that caught my eye was the exhaust fan.  Depending on the heating system you have, a negative pressure inside can cause carbon-monoxide problems.  Where I live, this comes up every winter when make-up air vents become blocked by snow.  Exhausting this much air may require additional vents to prevent products of combustion (CO) from being drawn into the living space.  We have code requirements regarding exhaust flow...even for hood fans over a stove.  You may want to look into the codes in your area if you think this applies to you...(you may have already done so too!)  Under floor heating below ceramic or stone tile would help dry things out after mopping...just a thought.

FYI

Steve

[drewstar]

Our big concern is mold on the floor when water splashes out.  We plan to sponge mop after each use. Any suggestions?    I would like to know if anyone else has a similar set up and how they deal with it.
 

Proper ventilation is the biggest thing you can do.  You also mentioned you're using green board, which is excellent.  A floor drain and regular cleaning of  the floor with a bleach solution would be other things to consider.  

Also, I understand there are mold resitant paints, (and additives to add to common paints that hinder mold)  This could be used on any painted surfaces.

[Snowbird]

The issue of carbon monoxide is important.  

We have a 90% efficient furnace with sealed seperate intakes and exhausts on the opposite side of the house.

Our gas water heater burns ambient air from the house but exhausts out the side of the house with the furnace.  I will check how negative pressure would affect it.  It is brand new (June) and hardly ever runs.

Also, this room is sealed from the rest of the house with 2 sliding glass doors (it used to be a deck off the dining room and family room).  The HVAC is the only opening between them.

My guess is any air exhausted will come from all over the house and basement through all those little gaps an older house (1969) has.

Thanks for the heads up about it though cause I never considered it.  Maybe a CO sensor is a good idea.

My wife uses a vinegar and water mixture to clean the tile floors.  Don't know if she will use it on the linoleum too.  It wouldn't hurt to replace the vinegar with a little Clorox.

[wmccall]

Nice view, what part of the country is this?

[Snowbird]

Pennsylvania - about 10 minues from the Pittsburgh airport.

[wmccall]

Pennsylvania - about 10 minues from the Pittsburgh airport.

Darn, I should have said Hi, I was in Erie for Thanksgving and then took my nephew to that airport. He is Iraq bound.  Back home in Columbus now.

[johnvb]

Excellent...another "insider"!

We have had our tub inside a remodel screen patio room for 5 months now. A few suggestions/experiences:

We change our air in the room once every 5 minutes, so you should be good there. Have the same setup as to "sealed from the house with sliding doors" except the HVAC.

One thing you may have to change is the fan control. A humidistat may run the fan too much. If you are using the tub in the summer, and have the windows open, with high humidity outside, that sucker may never turn off. The humidity in the room when using the tub will be like someone taking a longgg hot steamy shower in your bathroom.

We use a manual switch that has a built in "off" timer, set to 1/2 hour after it is turned off. Another advantage to this is I can pre-purge the room from any ozone off-gassing, before we use the tub.

Makeup air needed in the spring / fall / winter is a non-issue for us, we just open the windows in the spa room. In the heat/humidity of the summer is the only time we don't open our windows, but instead steal conditioned air from the main house.

Also I have found that in the winter, not to open the windows until the spa is ready to be used. If you cool the room down too much before, as soon as the cover is removed and stream hits everything...drip city.

My spa room HVAC setup, when it is finished (held up by other construction) will have the main HVAC supply air going into the room. The spa return air will go to an ERV unit, which sends it outdoors. The makeup of the ERV from the outside goes to the main return duct. So I will be using the spa room as the ERV "plenum box" so to speak. The manufacturer claims that 70 % of the energy in the expelled air will transfer over to the incoming makeup air...we'll see.

Your issue with water on the floor is kind of an inside joke around here. I told my wife I was going to get a dedicated wet vac for the room, because of the same concerns. Lowes sells some cute little units that look like R2D2.

Well, very little water gets on the floor (porcelain tile with water sealed grout). We have a towel we use as a floor mat, next to the steps. I just "walk" around the tub, wearing the towel around my feet, to dry off the floor when we are done.

Most of the water that gets on the floor comes off the cover when it is removed. Since we don't use a lifter, I have learned to pull both ends up vertical first, which drains water off the bottom of the cover into the spa.

Not sure how big your room is, but in mine (14 x 11.5 x 8 ), I wouldn't install a TV in it unless I could do some sort of airtight seal between it and the room, like a built in cubby.

One last thing. Never leave the cover off for any long length of time, (even when the main pumps aren't running), with the windows closed, and the ventilator not venting. Not unless you want to use that mob on everything in the room! (BTDT)

[Bonibelle]

Just wondering if a skylight would make a difference.
The ones we have , have vents in the top so that they can vent out hot air even when the skylights are closed.

[Snowbird]

Thanks for the advice John.  There is some good stuff in your note.  

"A humidistat may run the fan too much."  & "We use a manual switch that has a built in "off" timer, set to 1/2 hour after it is turned off."

It is our intention to allow the humidistat to control the air when we are not in the tub and the room is shut tight, as it will be in the winter.  The idea is to keep the room around 75% humidity.  If it runs too much then we will have to consider something else like mushroom farming or growing stalactites(?) for museums.  

In the winter, when we are in the tub, we will turn the fan off and either have the windows open a little or just let the humidity go and control it after we are done.  In the warmer months we will turn the fan off and leave the windows open.  The breeze will keep things cleared up pretty well... we hope.  If it is too hot, we will close the windows and use the AC.

"We have a towel we use as a floor mat, next to the steps. I just "walk" around the tub, wearing the towel around my feet, to dry off the floor when we are done."

This what I expect to do as long as there isn't too much water.  If there is a lot we will use a sponge mop.

Your idea about the cover is a good one.  I might have thought of it in 6 months or so.  We will probably have a lifter.  That 8x8 cover is too much to handle alone.

The room is 12 x 18 with a sloped ceiling (9'5" to 7'5").  The TV will be as far from the tub as possible and I hope the fan keeps it and the stereo operating.

Hi Bonibelle. We considered a sky light but we are going through a lot of work to eliminate anything going through the roof.  All that is left is the sewer gas pipe.  Plus the cost of an acceptable skylight was more than I had left after a remodel that includes roof, windows siding, new french drains, enlarged front porch with roof and the enclosed hot tub room on the back.  When we retire in a few years we can each free government cheese in our hot tub while watching the Steelers.

[johnvb]

Thanks for the advice John.  There is some good stuff in your note.  

"A humidistat may run the fan too much."  & "We use a manual switch that has a built in "off" timer, set to 1/2 hour after it is turned off."

It is our intention to allow the humidistat to control the air when we are not in the tub and the room is shut tight, as it will be in the winter.  The idea is to keep the room around 75% humidity.  If it runs too much then we will have to consider something else like mushroom farming or growing stalactites(?) for museums.  :

You may be ok with the humidistat. I have a cheapo wall mounted temp and humidity display in our room. Sometimes it reads 40 %, sometimes 75% (with the tub cover closed). If humidity/mold in the room gets too bad, you could add one of those small portable dehumidifiers.

Don't forget to add some live plants in the room. We have a palm tree and some other hanging plants in front of the windows. They are doing quite well. I just have to make sure the room temp doesn't go below 45 degrees.

I'm pretty sure you are going to want the exhaust fan on while the tub is uncovered. I would want to get the humid air out of the room, ASAP, before it has a chance to build on the walls/ceiling and starts dripping down. Once that happens, you'll have streaky watermarks everywhere.

If the fan is too noisy, sonically isolate it from the room by using an 8-10' section of insulated flex duct between the room intake grille and the fan.  If using a ceiling mounted unit, you could build a plenum box to mount it on, then do the above.

As far as a lifter, I imagine I will be installing one someday. I can balance mine on my knee and throw it on but is still a chore.

[Snowbird]

The fan requires ducting so we will put it at the end of 25 feet of insulated AC duct.  It is 62db (normal conversation) so 25 feet away with an insulated wall and and insulated ceiling in between, it should be pretty quiet.

The analog (dial) humidistat was moderately priced and the dealer guarantees it, so setting it at 70% should maintain 70%... I hope.

Might give plants a try. Maybe a hanging basket in the corner.  

[johnvb]

Good luck, keep us posted.