Darkroom building/ventilation advice

[blaze-on]

I am currently under construction on my "in house" darkroom. I've partitioned off a back room to include no windows, have 8' x 11' and 99" height so my Durst L1200 sites fine on a 30" high table.

I plan on putting in a laundry type deep sink along a wall that falls between two small corner closets which will contain print dry (fiberglass screens) racks, shelves for chemical storage, film drying,etc.

I think I will build a box shelf above sink about 5' high that will contain two bathroom exhaust fans and vent them (ea.) straight up into attic...shelf can also be used as, well, a shelf!

Q#1) Is that acceptable, or should they vent all the way to the outside?

I will most likely go vertical with the trays next to sink as I will be limited to 6 feet of width in that space.

On the opposite wall from sink, where my 6' counter will be, I am thinking a set of 3 or 4 2.5 inch tubes, elbowed twice (in the wall) to have airflow into the room. This incoming will be from the house-not outdoors and they will be set low from one foot to about three from floor.

Q#2) Is this enough? Too much? Or other suggestions.

I am trying to rough this in while trying to keep from messing up the house too much. It is also my own first darkroom. No more stepford labs for me.
There will be six dual electric outlets, which someone will say "not enough", but that be the way it is...

I also have finished wood floors-vintage 1938 that I refinished, so I may lay down something overall...any thoughts?

Your experience is appreciated-thanks.

 

[Nick Zentena]

venting potentially moist darkroom air into the attic doesn't sound like a great idea to me.

 

[Neil Souch]

Hi,
Re ventilation etc. Sounds OK. I have one big kitchen extractor going via a duct into my loft and it is wired up through a stat (suitable dimmer switch) to control the speed and noise! The loft needs to be well ventilated though and not connected to a neighbour in anyway. My house dates back to 1881 and I have had no adverse problems with venting into the loft, but it is a large a drafty loft. I ran a load of that flexi vent tubing across the joists to a suitable drafty exit spot! I am sure this is a bit naughty though and if you asked you local building control dept they would want it venting externally. I would do it and take it away if you ever move, unless you can easily do an exteral exit.

Enjoy finishing off your darkroom,

Neil.

 

[Aggie]

Matt, You're in California. They most likely will requitre it to be vented outside. Also do a quad type electical outlet, at some of the points, where you might have more usage. Better to have too much of the outlets than not enough. You most likely will be doing the finishing stuff outside of the darkroom. The floor I would proctect with those linking type rubber mats. Geary has some in his darkroom, and will probably chime in where to get them.

 

[rbarker]

Venting through the roof is probably preferable, but adds complexity, cost, and other risks - unless you have it done by a professional roofer. Venting into the attic crawl space may be OK, depending on whether it is well-ventilated to begin with, and whether it's a real "attic" used for storage or just an unfinished crawl space. As Neil suggests, local building codes may be far more restrictive with respect to venting, your electrical, and the plumbing.

Laundry-room style deep sinks are attractive from a price perspective, but might be tiring to work with. I think I'd suggest a sink depth that doesn't require you to bend over to access smaller items at the bottom of the sink - 8" or so deep, perhaps. Also, you might consider a faucet with the tall, crooked spout like they use for bar sinks. One that incorporates a hand sprayer nozzle is convenient, too.

Linoleum or asphalt tile flooring would probably be a good idea, as well. Any chemical spillage on the wood floors might cause other problems.

 

[RGyori]

Venting

From a photographer and architect...

Discretion frequently being the better part of valor (or expediency) I strongly recommend that the darkroom be vented to the outside, even in warmer and dryer Southern California... particularly if the attic space is contiguous over other areas of the house. I would not rely on the natural draft in the attic to reliably remove the moisture and odor.

 

[blaze-on]

I appreciate the "bend over" problem pointed out Ralph, good point. It's always easier to envision something when one hasn't had hands on usage to learn the "wish I had done this" stuff. Maybe a sink "insert", a base that actually raises bottom up enough, unless i can find a used stainless from a defunct commercial kitchen or something similar that is not so deep. But I am a messy sort when i get crankin' on stuff.

My house just got a new roof so i don't want to go through it, but I did add two turbine roof mount vents, and there are slat style vents at both ends of house in gable peaks. Perhaps I'll run some flex pipe to the vent areas.

What about the "in flow" pipe vents from the house air? Ok?
I was told that it would bring in less dust than from outside. Thoughts?
My reason for this is to only have holes in the "faux" wall, which I'm building so that it may be taken down easily enough for the future lucky owners of this house..

Thanks to all so far, and yeah, Aggie, I guess a four banger instead of a double is easy-good idea.

I'm doing it all myself, and am fairly competant at most of this-especially demo work.

 

[Aggie]

Why not make your own sink? It can be done out of plywood and lots of marine sealer paint, epoxy and other stuff. Many here have made their own. To bad you are not doing this on the side of the room that has a window. You could get a board to fit the window space, and put the vent in it. Then no extra piping, orproblems with knocking a hole in the wall.

 

[blaze-on]

Why not make your own sink? It can be done out of plywood and lots of marine sealer paint, epoxy and other stuff. Many here have made their own. To bad you are not doing this on the side of the room that has a window. You could get a board to fit the window space, and put the vent in it. Then no extra piping, orproblems with knocking a hole in the wall.

Ah, the best laid plans...The window is next to an exit door. Not good.
I'm still in a deep thought process about overall layout, so the suggestions here will play a valuable role, as my depth of thought is less than my desired DOF, and that isn't a good thing

Keep 'em coming...

 

[oriecat]

This thread reminded me of my own ventilation issue that I have been ignoring. I put my darkroom in my basement. There was already a fan down there, but it vents into the crawlspace under the house. I used it once when I painted something and the whole house ended up smelling like paint, so I have not been using it for the darkroom. The dryer is also down there and vents outside and I was wondering if it is somehow possible to make the two vent to the same hole outside.

 

[oriecat]

I have a cheap laundry sink also, and I don't have any trouble with it. It's deep enough to easily clean my larger trays, and also prop them up in there to drain and dry. And it was only like 20 bucks at Home Depot.

 

[Bob F.]

Couple of thoughts (two being the maximum amount I can handle in a short space of time)...

Make the bottom of the sink at a comfortable height for rocking the dishes: I found I preferred the bottom of the sink to be about 4 inches lower than the dry side counter (which bought the top lip of the sink to about the same height), but I am 5'7" so if you are taller....

I used to ventilate in to the loft in my previous accommodation which had a windowless bathroom with a ventilation fan blowing into said loft. Worked OK(ish), but the fan wasn't really up to the job and a faint odour would permeate the whole place on a calm day...

My current 'proper'(ish) 10' square darkroom blows air out through two 6" bathroom fans mounted on a board fixed over the window. Just about enough air movement but noisy. Long term plan is to get an industrial fan and move it outside and use ducting to suck the air out: no noise. If possible, think about putting the fans in the loft with ducting coming in to the darkroom and do the sucking business if you go down that route - I found that any wood you mount the fans on to acts as a sounding board to magnify the noise...

Have fun! Bob.

 

[Aggie]

Since the dividing wall is not permenant, who not cut a hole in it, use that funky flexible ducting tubing to go to the window and sue the vent on a board in it? Then when you move, you can take the vent with you.

 

[rbarker]

The more I think about it, the less I like the idea of venting into the attic space. Remember, the convection in the attic is based on the assumption that the air entering through the vents at the lower edge of the roof will be cooler than the air at the top of the space. How the air from inside the darkroom might fit that temperature range at different time of the So. Cal. year might present a problem.

I like the idea of using flexible ducting and a drier-style vent (to the outside) much better. That would also facilitate placing a stronger duct fan outside the darkroom, and midway along the flexible duct, to reduce noise.

I would not, however, try to connect a Y fitting to an existing drier vent tube. Too great a possibility for drier lint to be pumped into the darkroom when the darkroom fan wasn't on.

 

[blaze-on]

I think I have decided it's best to vent directly outside....The sink area will be to an outside wall, and a small hole for a drier vent hose will be fairly easy to patch if needed.

I think I'll also build a sink outta wood, which will allow a more custom fit to my arena anyway.

I also think for incoming vent I will use the space between the 2x4's in new wall and put a couple HVAC wall vents on opposite sides, one at top, one at bottom.

Now just have to figure out plumbing route et al. Bathroom adjacent and I was originally going to keep it a dry dkroom, but I think I'll be happier with everything I need (or think I do) all in the same room.

Thanks to all for the great suggestions and concerns. I'm always willing to change my mind if there's another thought or more out there. Peace.

 

[Monophoto]

In general, the best way to ventillate a darkroom is to blow air INTO the darkroom through filters (to remove any dust). What this does is cause the air pressure inside the darkroom to be slightly greater than outside, and any parastic air flow will therefore be from the inside out. As a result, you get better control over dust.

Using a joist or stud space for ventillation makes lots of sense, but one of the challenges is getting something that provides decent air flow but that does not create so much noise that you can't think. In my new darkroom I used the space between a couple of floor joists to construct a box. I put an air filter between the joists, and then mounted a small computer-type muffin fan at one end to draw air through the filter. Then, I used a length of plastic vent pipe (the kind intended for ventillating bathrooms) to direct the air from the outlet of the fan into the darkroom. Making the box separate from the darkroom, and using a muffin fan, made the resulting ventillation system totally silent.

Plumbing in a darkroom is another problem. Getting water in is relatively easy - but getting waste water out may not be, especially if your darkroom is in a basement. I collect water in a reservoir (a large rubbermaid tub), and then use a sump pump to lift it to the point where it can flow down into the house drain system.

 

[gma]

I hope you will keep in mind that you might move someday. Patched holes in siding will be hard to explain and fixer odor will be almost impossible to remove from the room.

 

[ChuckP]

Don't forget to check Ebay or other used places for sinks. Sometimes you can find a good one much cheaper then building one yourself. I like your incoming air design using the space in the wall with high and low grilles. People say to paint the inside cavity with flat black paint. Make sure that the air flow doesn't pull the air back into you from the sink. One slick method I've seen used a large Plastic pipe/tube with lots of holes drilled in it mounted along the back of the sink. The pipe was connected to an external blower to pull air out of the room. Ideally you want your air intake set to pull fumes from the trays away from you not up and over your face. To find your fan CFM figure on needing 4-5 changes per hour. But I'm really not sure how much you have to lower the rating of the blower to take into account your ducting system.

 

[blaze-on]

I perhaps should have mentioned that within this new area to be, there is a return air vent in ceiling for the central HVAC system. What effect, good or bad, will that have?

I understand there is a positive or negative pressure vent possibility, but I am not sure which is best or ideal.

I will be remodeling the adjoining bathroom which needs a new subfloor and will be building a new shower in parallel with the darkroom sink separated by the wall. My thought was to run the drain from dkrm sink through this wall and leave one blank 4" tile square in the shower wall for the drain pipe to fit through and just let it run into shower drain. I will fabricate a cap to fit this while shower is in use. kinda cheesy but it eliminates the tearing open of walls or floor for plumbing. Thoughts?

The house is on a raised foundation. If I were willing to open the floor up for plumbing, it would be a piece of cake, but the wood floors are original and as mentioned, refinished.

Some good suggestions that have helped me further define my approach-thanks.

 

[Jon Shiu]

About ventilation, using two bathroom fans above the trays and vented to the outside sounds good. You can get quiet fans - they are all rated for sones and cfm. Positive pressure and remote fan systems would not be efficient and would require industrial size fans to work properly.

 

[jp80874]

Hi,

Built my first darkroom a year and a half ago after a year using a University darkroom. I have learned that a darkroom is an evolving place. What made sense two years ago has been over ruled by what I have learned to do, what I have learned I want to do and the courses I’ve taken.

I put in 14 electrical outlets, twice the number I needed. Two are free now. I suggest ground fault so we can continue this conversation after the first spill.

Bathroom fans are noisy. I spend a lot of time in the darkroom, some times in silence, some times with music I enjoy. On another form I learned about Panasonic fans. Very quiet. A 70 cfm 7” fan pushes air into the room from the basement through a high quality furnace filter. On the opposite wall two 120 cfm 4” fans suck air from the far side (from me) of a 5’ x 20” SS sink outside through 4” white PVC drain pipes. All you can hear is air moving through the pipes. The fans came mail order from South Cal. I can get part #s and source with a little looking.

I have a concrete basement floor. Half inch rubber mats feel very good after an hour or two.

We have a well and a septic tank. The local University lets me put spent fixer through their silver recovery system rather than back in my well. They help fund photography. I get to live a little longer.

Good luck. Remember that the best plans often get changed by even better ones.

John Powers

 

[blaze-on]

14 outlets-wow. I can't seem to fathom what all those would be for, but I'll add a couple more to be better equipped. The Panasonic fans sound good John, and the web link or phone would be awesome-thanks.

The planning is tough...am anxious to start drywalling the new wall, but best to know exactly what I'll be doing so thanks to all.

I'm even thinking a canopy or sorts (like a stove fan type) over the sink area
now....all responses have been helpful. Thanks.

 

[jp80874]

I hope I didn't mislead you with 14 outlets. I meant 14 plugs rather than 14 multiple outlet fixtures.

I bought the fans from:
R.E. Williams Contractor Inc.
25876 The Old Road #71
Stevenson Ranch, CA 91381

Toll Free: 1-888-845-6597 http://www.rewci.com/

Panasonic Whisperline FV-10NLF1 Ventilation Fans
5505.71-FV10NLF1 120 cfm This mounts in the rafters and is used as my exhaust. The intake goes through white 4” drain PVC to the back of the sink. The exhaust goes outside through a flapper to keep the bugs out. I started with one and added a second three months later. You don’t need a riggers line to stay on the floor, but fresh air is good.

Panasonic Whisper Wall™ : Wall ventilation fan 70 cfm - Free Shipping
FV08WQ1 You have to build a frame in the wall to hold the furnace filter for this.

Besides fresh air for breathing (does there have to be another reason) as another poster mentioned this drastically cuts dust. The only way I can quantify what that means is that next week I need to present twenty two 11x14” B&W prints as a final for my advanced photo course. I mounted them yesterday and as I went over each one I decided that one picture needed to have one pin head size spot toned. If that isn’t worth the investment then go for the breathing as justification.

What to I put in 12 outlets? Can’t stress ground fault too much.

One plug in fluorescent fixture beyond the regular lights.
Safelight - Jobo
Hair dryer - Radio/CD player
Air purifier (not using yet so that didn’t catch the dust)
Enlarger - Enlarger timer
Light table - Printer dryer
Clock - Sweep second timer

Later this month I will add UV light source and densitometer for platinum printing.
I’m out of plugs. Obviously everything doesn’t go on at once, but my plan of doubling my need 18 months ago wasn’t enough.

Good luck. Be safe and enjoy. I’m 64 and having a ball.

John Powers

 

[blaze-on]

Thanks John for the lead on fans...sounds like the way to go. I'm sure others might appreciate that info as well.

 

[jstraw]

I thought these ventilation links might be helpful to others:

http://www.suncourt.com/

and as a supplier of these and other items:

http://www.hvacquick.com/index.php