Hey people,

I would really like to see some of your pics of obvious signs of a grow-op (i.e tap into hydro, etc), tips of how to determine grow-ops, etc.

Since this is a growing concern (no pun intended) an updated discussion might be a good idea. Besides it getting close to harvest time and we might start seeing more of them on the market.

A couple of months ago OAHI offered a one-day seminar on grow-ops but as usual it was during a week day and cost $150 bucks or something. No time & no money means no seminar. Typical dilemma when your a student member of OAHI. But enough of that!:smiley:


Hey Chris

How do you know when harvest season starts? Ha Ha just kidding. I attended a very interesting seminar related to this put on by the Ottawa Police. If I see one come up again I will let you know.


Well, I’m still a fairly new to the HI business and bills still have to be,… just kidding,… beside we are at least 6 weeks from harvest time. How do I know? My best friends cousin is an OPP officer that flys around the Ottawa area looking for crops.

Was this through OAHI? This is what they did but charged $150 bucks!


Been there done that . I expect NACHI will soon have one and you can be sure it will be a lot less then that .
Roy Cooke sr . RHI. CAHPI-ONT

Thats another use for thermal imaging cameras. Local law enforcement wants me to ride along with them this week to look for suspected grow ops. I am looking forward to it!
I am gonna talk to local wildlife guys, too and see if they could use my help when they do aerial animal counts.
As far as other indicators go, I think they sometimes have extra ventalation to get rid of smell, windows boarded or otherwise blacked out.

Bob Francis and myself were allowed to attend the Toronto Arson Task Force Seminarlon Marijuana Grow Houses. It was most interesting and it is amazing what some motivated grower will do to hide the operation and power use.

Bob and I were honoured to be the only two home inspectors invited to attend. The police and others involved, RCMP, et al were hesitant. But Bob Francis and his smooth talk got us in. We even got Certificates of Attendance for CEU purposes.

The case ruling on thermal imaging in Canada in regards to case law can be found here. An interesting read. Which I believe from memory was mentioned at the seminars is found here at these links.



I Took This Course Recently From 'iaq Resourses Canada’and They Talked A Little Bit About Grow Houses.very Interesting Course It Was About Mold The Cost Was $375.00 But Worth The Cost.this Article Is From There Web Site.


One Sign Of A Grow House Is White Paint In The Basement Or Attic This Paint Is Aluminium Oxide Paint And Is Used For Masking Smell Of Grow House Or After A Fire Has Occurred In A House.


They talk about doubling the fines . Big deal I wonder has any one ever paid a fine .
What about the Largest Grow house in the world just North of Toronto in Barrie The old formosa Brewery.
Lots of front page and suddenly no more information .
They get a small house in Scarborough and it made the head lines and now is listed by the police constantly.
Roy Cooke sr… RHI

Just did an inspection on a grow op house. The client that had just bought a 3 year old house and found out from the neighbors that it was a drug house and they were deeply concerned about the mold possibilities. So I went through it quite thoroughly, including moisture testing all walls, removing and looking in any access panels and cold/hot air registers. Turned up nothing but a couple of minor items that didn’t or wouldn’t have made me suspicious that this would have been a grow op.

We noted that thin white styrofoam had been nailed to the un-finished basement joists…probably for light reflection and some moisture barrier. The perimeter of the drywall walls had a bead of some type of silicone or caulking around the top and around the windows, which was likely what they fastened the black poly moisture barrier to and to keep the neighbors from seeing in and blocking all the lighting. People do get to wondering why such bright lights are on 23 hours of the day;-) There was also about a 10 inch hole cut through a closet floor and ceiling which had a panel covering it up. This would have been for the extra ventilation needed to keep the moisture level down. In the attic the ventilation had a large plastic bucket with screening on both ends and the bucket was full of those scented dryer sheets to mask the smell.

I told the client that even if they had a home inspection done by my wife and I, that we would not have known this was a good sized grow op house. (and we are pretty thorough and fussy)

The most ironic thing was the client was a new recrout for our local police department:shock: :shock: :shock: Now thats bizarre;-)

I talked to a lawyer and Mortgage Broker ( 2 ) and My insurance company.
The lawyer says look out here comes the litigation . The motgage broker say they do not think they can get mortgages . The insurance agent phoned two companies and both said they would not if they knew ever give insurance for that home .
I would say you do the same and see what you hear I and others would like to hear what you find out .
The Grow houses I have done it was quite noticable what they where
Roy Cooke sr

Raymond- wow, what a great read on law cases involving thermal imaging. I’ll make sure that my cop buddies are aware before I proceed any further.
Thanks alot!

Good article! They quote some stats on how many homes are condemed in Calgary,… does anyone know the stats for Ontario, Ottawa and Toronto?

More info as I receive it Here is the latest.

Go to then Star columns look at april this year
Roy Cooke sr

Have done 3 grow houses this year. We get the calls from tghe goverment after the house has been seized under thr proceeds of crime act and are acompanied by the police while we do the inspection.Have not found any real bad places as of yet.Bars on windows that kind of thing and some changes to the electrical like the last one dry disconnected at panel so they could use it for what ever.I even had one right next door to me 2 years ago but they got busted,3 day in jail and $ 5000 fine 25 plants and 30.000 in stolen property.Get system we have here.

Seems to me that the whole grow-op thing has gotten out of hand. I inspected a house where the owner admitted that there had been a small grow-op and there was nothing wrong with it. The bank was freaking out and threatening to stop the loan… I had to categorically state that the problems the house had were not grow-op related. I happily did this and the buyers got their house.

On the other hand, when the owner is trying to hide the fact that there has been a grow-op you have a totally different scenario.

It’s all about wiring and moisture, I certainly don’t want to get involved in the right or wrong argument or the war on people who want to smoke the stuff.

Personally many of these homes have been needlessly stigmatized.

I know that the house next to me was never disclosed as a grow op buy the vendor or thier agent and I believe this has to be done reguardless of the size of the operation.I did talk to listing agent about it and was told they did not have to disclose because it was less then 30 plants,talk to the OPP and they concider any amount of plants a grow op.Does anyone know what makes a grow house.

Hi Rob,

I think you will find that the police have to prove intent to sell the product. At some point the effort to find and prosecute becomes a factor. Needless to say quantity does factor into the equation. I think you will find and …you can sleep at nite …if you grow maybe a maximum of 5 plants, anything more is considered cultivation for the purposes of selling an illegal substance.

From what I understand first time offenders for large quantities have been getting off rather lightly according to the people at the seminar I attended. But that seems to be the case with many criminal cases and sentencing in Canada.

New law as of Aug I 2006
If it has been a grow house it can not be sold untill examined by the local building inspector .
This should be interesting as Building Inspectors I am sure will want nothing to do with a grow house . They have not enough time now to do a building inspection with out going and checking for mould and repairs both building and electrical . This vcould be an opening for home inspectors who are more experienced in inspecting finished houses and also they HI will take more time to make sure the work is satisfactury
Roy Cooke sr , RHI CAHPI-ON… Royshomeisnpection,com