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IRC Indoor Grow Rooms

Glenn

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Joined
Nov 1, 2012
Messages
889
Location
Denver
There's never been anything stopping someone from growing tomatoes, basil, or other veggies and herbs in their homes...but it's just not that popular of an hobby. Some folks are really into African violets.

However...in Colorado and Washington...there's a new motivation on the horizon for constructing grow rooms in homes. Legalized marijuana. As the first governments in the WORLD to legalize (not "decriminalize) marijuana, my fellow statesmen and I will be the trend setters in how to accommodate this use in an IRC dwelling. I presume over the next few decades we will see more legalization across our nation.

This thread is not intended as a sounding board for your opinions about MJ. In Colorado 1.2 million voters circled in the "yes" bubble, so it's time that we accommodate this new "occupancy" inside IRC dwellings as directed by the democracy. Like it or not.

So...what does an indoor grow room mean to "the minimum standard of construction"

Electrical: Should all the outlets be GFCI protected? Dedicated circuits for ballasts? I'm no expert here...but it seems the IRC doesn't accommodate electrical provisions for grow rooms. What does the NEC require?

Energy: There are continuously running exhaust fans in these rooms. How does that affect energy? We're talking about serious CFM's

Moisture: Are the exhaust fans good enough? Should there be vapor retarders?

Building: Is the typical 10 lb dead load and 40 lb live load (or 30 lb if bedroom) enough to hold all the pots, soils, water, etc? I don't know.

Mechanical: How does the existence of 1000's of watts of lights affect the Manual J load calcs? Perhaps new custom homes will be built with grow rooms incorporated into them.

Indoor environment: CO2 is released in the air to ***** plant growth. Is that a hazard? Should the doors to grow rooms be gasketed and self closing?

Fire: Is there now an increased fire hazard? Should these rooms be provided "drywall separation" like a garage?

Plumbing: Mechanical rooms typically get floor drains. Should grow rooms require floor drains?

What else: ??????

The IRC has provisions for surgical rooms (G2406.2)...maybe it's time to include grow rooms! ha, ha!

Our Colorado ICC chapter had some discussion about the above topics back when medical MJ was approved. However, most folks still kept in on the down low. Now that it is full legalization, I think it's more likely people will proudly walk in, slap down their basement finish plan, and happily declare their grow room in the corner. (in Colorado...very likely)

Let's start the discussion. It's a whole new, fresh topic to "hash" out and set a path for two states in our union.
 
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Glenn,

You have opened a real can of worms on this topic.

QUESTION # 1: How is enforcement / monitoring of growing tomatoes, herbs,

plants currently handled for Residential?

QUESTION # 2: At what point does it change from Residential consumption to

a Commercial operation?
 
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Worms are fun. As long as we keep it on topic. The decision of the law is made; it's our job to accommodate. That's the topic.

As for your question...I have no clue. That was the point of my leading statements in my original post. I have never had someone propose a full-scale grow room for veggies, so I have no idea. Up to six plants are allowed under the new law. Those plants can get big, fast.

"What" is being grown is not our concern. The manner, materials and equipment used is.
 
Thanks Glenn for your reply!

No, we are not discussing or debating whether or not it's allowed.

Six plants can go to six trees, or at least full blown & developed shrubs,

relatively quick, so it sounds as though the Colorado legislators will have

to decide when it is no longer "for personal use" and is now a Commercial

operation.

Was there any guidance / language provided in the recently passed

legislation for parameters of the six plants?

.
 
Look at what is done for indoor swimming pools, some similar problems.

Yes they are a fire hazard, mainly electrical issues
 
Typically, most indoor grow areas are something akin to a greenhouse.

I am not sure that the IRC can regulate them, unless the plans indicate a greenhouse,

or the environment similar to a greenhouse will be constructed.

All of the things in your OP would be affected (moisture barriers, electrical, mechanical,

plbg., energy efficiency, MOE, and on and on and on).

There are some rather small enclosed structures out in the market that might not

require anything. See the link: http://www.ourcrazydeals.com/indoor-greenhouses.html



.
 
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Legalization will change the economics such that there will be less incentive toward commercial techniques.

Over the long term, it will be no more a problem than motorheads maintaining racecars at their house.

What isn't needed is a bevy of knee jerk reactions.

The existing codes handle it adequately.

The real issues are education (primarily) and enforcement of existing codes (secondarily).
 
I agree brudgers about no knee jerk reactions. That is why I prompted a discussion early. I don't know how the existing codes will handle this. If they do...please talk about it. The provisions in the codes are dependent on use (bathroom, kitchen, bedroom, unfinished space, habitable space, garage, mechanical closet...now...grow room?) What is a grow room in that respect? Just like the list of rooms with special considerations due to their special use...a grow room has some very special features and equipment for a very special use.

To clarify, I am talking about INDOOR grow rooms, not greenhouses. In Colorado and Washington (northern states) the operations will be indoor. They will likely be in a basement.

Globe Trekker. I am talking about non-commercial operations. An INDIVIDUAL can grow up to 6 plants legally under "possession" for themselves. NOT for resale. Just as legal as my jade plants are, but limited to six.

Motorheads use garages designed for that purpose. It's not a new "use". Homes are not designed with any rooms prepared to accommodate an indoor grow room. BIG difference.

I can't stress enough how common this is already (under the radar) in Colorado. The legalization will make this much more common and brought into us for review. I am confident of that.

How do we define the "minimum standard" for these rooms in terms of features or performance they MUST have. I am not talking about that proper installation of features and equipment CHOSEN to be installed. Yes, existing codes handle that.
 
2009 IRC

It is important to understand that the IRC contains coverage for what is conventional and common in residential construction practice. While the IRC will provide all of the needed coverage for most residential construction, it might not address construction practices and systems that are atypical or rarely encountered in the industry. Sections such as R301.1.3, R301.2.2, R320.1, R322.1, N1101.2, M1301.1, G2401.1, P2601.1 and E3401.2 refer to other codes either as an alternative to the provisions of the IRC or where the IRC lacks coverage for a particular type of structure, design, system, appliance or method of construction. In other words, the IRC is meant to be all inclusive for typical residential construction and it relies on other codes only where alternatives are desired or where the code lacks coverage for the uncommon aspect of residential construction.

I doubt anybody will tell you they are installing a grow room in their new house and the existing homes will not tell you either.

Do not even go down the road you are opening the gate on. On second thought close the gate and lock it then throw away the key
 
Let's get back to basics: Who died and made us kings?

That is, being that a mans' home is his castle, what he does in it is his own business, and it's not for us to write 'rules' for him to follow. IMO, there is NO governemnt body that has any business monitoring anything legal one does in their home. Period. Let's not turn the codes into and end run around the people's right to be secure and safe from unreasonable searches.

Now ... from a design point ....

Keep in mind, as well documented in the book "Licit and Illicit Drugs," the main problem with drug laws is that they drive folks to even more dangerous behavior. For example, filling their basement with 'outdoor only' fire-hazard HID lights.

Let's also look to the show "Holmes on Homes," and his repair of a house used as a grow-op.

What are the problems faced?

Well, there's the matter of utilities. The Holmes house had all manner of improper tie-ins to the plumbing and electric. Nothing that can't be sorted out by the typical tradesman ... though one might want to allow for it in their load calcs.

The biggest problem was mold, caused by inadequate ventilation, and made worse by use of materials that didn't handle high humidity well. So, we're looking at some serious ventilation of the growing area. Fresh air direct from outdoors ... and exhaust directly outdoors too.

Electrical is a big thing, with the large number of lights used.

So ... for the plans examiner ... if you see a plan with a 'garden,' what do you look for?

First off, I'd scratch that area off the list of 'habitable rooms,' and treat it for what it is. On what is the load calc based? I would not just accept the usual 3W/sq ft. I would not expect the usual receptacles. I'd expect supplementary HVAC, and want the place isolated from the house HVAC.

Considering the humidity, I'd look for "WR" electrical devices, and seamless boxes at plant level. Whether to use 'outdoor' covers, etc., depends on the specific location as well as the watering methods. GFCI's in the panel, and the panel outside the humid room.

Instead of the sure-to-fail vapor barrier, I'd look to walls filled with foam and covered by tileboard and FRP. I'd want the ceiling sloped, to shed condensation. All wall lumber pressure-treated. I'd want the floor to be either a concrete slab, or to 'commercial kitchen' standards.

Plumbing: pay extra attention to the vacuum breakers and drains. I'd also look for a way to divert my 'gray water' to the plants, before sending it to the sewer.

Access? I'd want a door to the outside, wide enough for a wheelbarrow.
 
Six plants should not require excessive lighting! Six overgrown behemoth shrubs

or trees is another matter. Some growers may use topsoil, others may use

hydroponics for their nutrient delivery.

If we (code officials) are or will be asked to assist in adherance to code

compliance, ..shouldn't we know what is being constructed to comply to? If we

are not informed, on some sort of plans, then we do not have any enforcement

or design of anything. If the homeowner wants to ill-construct something

because of their choice to privacy, then we code officials cannot be expected

to assist.

Essentially, if the homeowner wants to use a room to set up operations,

then they will be responsible for the design or failure of the room and

the crop.

How many people come to code officials now to ask for guidance on setting

up their indoor rose (or herbal, or flower) growing operations? What's

the diff.?

FWIW, I agree that "a man's home is his castle!"

Glenn,

If chemicals are used (i.e.- hydroponics), would a dedicated backflow

preventer be "REQUIRED" on the potable water supply line to the hydro ops.?

Also, typical hydroponic ops. do not have much waste water. They simply

filter and re-nutrify.

.
 
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Great conversation.

I think we all love the rights we have to our castles, but that's not much of a argument on this topic. You can't have a room 6.5 feet wide, or a bathroom without ventilation, or a bedroom without a big window/door, or a bathroom sink without a nearby receptacle, or an unfinished room without GFCI protection, or a garage without a self-closing door (code edition dependent) or closet shelves too close to your light...depending on the light you choose, on and on and on. We stick our noses in all kinds of kingdom freedoms based on the stated or intended use of the room. An indoor room for growing plants is a HUGELY unique use.

You can however have every single door inside your house only 4 feet tall if you want.

The "USE" of the room is our business. If you call it an office...it's not regulated as a bedroom. We require every room to be identified and labeled for their intended use on the plans. How shall we respond when we see one labeled "grow room". Please get past the opinion that it's not likely...because I live in Colorado where it IS likely.

I don't care about the quality of their crop anymore than I care about the dress tailored in a sewing room. I do, however, care about the sewing room
 
"Amish Electric" has provided some very good basics and things to check while

doing a plan review.

One other thought is that in Colorado (and Washington), I am told that it gets

somewhat cold. The growers might consider a back-up source of electricity

for "the room". The family can freeze if the power goes out, or huddle around

the fireplace to stay warm, but the crop must be preserved! :D

Also, as "Amish Electric' has pointed out, "the grow room" will probably want to

increase their thermal insulation completely around it to have better control of

the temps. All electrical would need to be rated for a wet (corrosive) environment.

Agree that a separate source of HVAC (or approved alternatives) would be

suggested, not necessarily required. If a generator is installed, it should take

in to consideration all of the systems dependent upon it (elec., HVAC, water

pumps, various appliances, etc.). I like the idea of a Commercial Kitchen type

environment.

.
 
We have been dealing with indoor marijuana grows for years. Since our DA allows 100 plants per person our City had to deal with the issue with a zoning ordinance. Our ordinance allows the cultivation of mj if the following conditions are met. The area cannot exceed 50 sq.ft. and not exceed 10 feet in height. The lighting cannot exceed 1200 watts. The use of Co2, butane, etc. is prohibited. It can be only for private use. A permit from the building division is required. This ordinance came into exist over 2 years ago and we have had zero applicants. There is just too much money to be made in mj and no one wants to limit the size of their grow. That is why the City is still making raids on single family residences.

I don't have an answer to this issue, but based on what we have seen here, I don't think many in Colorado and Washington will be coming into the building departments to get permits. Most people don't want others (especially government) to know they are growing. Even though our president made his comment about mj, it is still a Federal offence and they are not going to take a chance.
 
The code does not regulate house plants.

Oregano, Basil, Chives, lemon tree, bananna plant, tomatoes, peppers, aftican violets, MJ are all the same to the building code--unregulated.

If adding new sink then plumbing permit to install and gfi around.

If adding new electrical circuit for grow lights then electrical permit the same as when adding a new circuit in the old kitchen so the microwave does not blow the breaker.

Time the growing so that plants are largest in the winter and then the cooling and moisture issues mitigate themselves--the lights act as heaters and the moisture helps the dry air.
 
We had a house with an indoor atrium in the core, stone walls, flower beds, gravel and stone paved areas, fish, carpenter ants, etc. You do have to take care of the indoor environment. Six plants in most circumstances isn't going to hurt anything. Really debating a Little Debbie franchise in CO.
 
"Really debating a Little Debbie franchise in CO."

Nope, Frito-lay.......they have the good stuff, Cheetos, chips, dips.....all sorts of crunchy, salty munnchy things!
 
Hey dude....you know it's my own personal herb you're messin' with, and...um....what was I sayin'? Oh yeah, I got some huge bud and......uh....anyway...see ya....gotta go get some munchies.
 
While we've been having fun I have been hard at work this evening. The pears have been squeezed and we're racking off after the first fermentation. I enjoy a bit of home brewing, I guess another hobby that has had federal stigma and another one that can involve heavy loads... but on a home scale I don't think either is of concern. When you push small commercial scale with anything it needs to be considered in that light. I'll probably need to do a little beefing up when its time to bring in the 20' vat for commercial production. The scale is not there, if it is you're designing a different building.
 
The price of California pot will enjoy a small hike due to greater demand. Not many people will start growing their own because it's not as simple as planting tomatoes. Anyone that wants pot can get it now so like booze and tomatoes, they will still buy it rather than grow it.
 
And, supply and demand, I think the price will actually drop for the product, as there will be some folks that push it to the limits...........
 
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