Grow HousesGrow Houses

Presented By

Pillar To Post

Gary Bostock

Course OutlineCourse Outline

• What is a grow house?

• How does a grow house operate?

• How does it affect the home?

• How can you recognize a grow house?

• Inspection & remediation

What’s a Grow House?What’s a Grow House?

• A home that is used for growing marijuana– small operation where part of the home is

used as a grow operation– larger operation where the entire home is full

of plants

• Hydroponics– Chemicals– Lighting– Water

Small Grow Operation

Large OperationLarge Operation

• Usually involved with organized crime

• MO #1– Home is rented from an unknowing landlord– Entire house is turned into a grow operation– Very invasive and may cause damage

• MO #2– Home is purchased (often with cash)– Entire house is turned into a grow operation

Lots of MoneyLots of Money

• One large scale grow operation in a modestly sized residential home– Average of 200 plants per home

• Stats from drug busts

– Four to six harvests in a year– $200,000 to $300,000 to grow operation– Adds up to about one million dollars on the

street

HydroponicsHydroponics

• Growing without soil– can set up a large operation without trucking

in loads of dirt

• Nutrients and water fed directly to the roots of the plant

• Light provided with high intensity lighting units

• Climate is controlled with ventilation systems

HydroponicsHydroponics

• Can grow entirely indoors

• Plants can be very close together– Roots don’t have to spread out in soil

• Faster growth

• Larger and more lush growth

Affect On The HomeAffect On The Home

• Electrical

• Structural

• Cosmetic

• Mold

ElectricalElectrical

• Lighting and ventilation equipment– Uses a great deal of electricity

• Ad hock modifications of electrical system

• Why?– Don’t want electric meter to suddenly show

increased energy usage– Don’t want to pay for the electricity

Stealing ElectricityStealing Electricity

• To avoid drawing the attention of the electrical utility and the police– Tampering with the meter– Tapping electricity from upstream of the meter

Meter TamperingMeter Tampering

• Remove the meter

• Insert a shunt

• Replace the meter

• Most of the electricity goes through the shunt instead of the meter

Effect on the HomeEffect on the Home

• Electrical tampering as described causes very little damage to the house– Removed the illegal panel and wiring– None of the household wiring has been used– Little chance that you have to worry about

damaged branch circuit wiring due to overheating

– Replace underground service cable and meter as necessary and your good to go

Effect on the HomeEffect on the Home

• Electrical tampering may not be so clean– The examples showed a very slick operation– A less savvy operator may cause significant

damage to the existing electrical system• Use existing electrical system• Install oversized breakers• Install oversized main breaker as well• Tamper the meter

How about the holeHow about the hole

• A hole in the foundation as shown causes no significant structural damage

• Fill in the hole

• Damp-proof the exterior

• You are good to go

Danger of FireDanger of Fire

• While the grow op is in operation– Danger of fire– An unsuspecting landlord could loose a home

to fire if the tenants are running a grow operation

• Let’s have a look at the risk

Structural DamageStructural Damage

• Damage caused by modifications– Not likely as big a problem as you might think

• Damage caused by wood rot inside the walls due to high humidity– Not likely as big a problem as you might think

How About Rot Inside The How About Rot Inside The WallsWalls

• Very high humidity levels could cause condensation inside the walls

• Grow ops try to control the humidity levels with ventilation– High humidity creates large leaves with low THC

levels (low quality)

• Still you could have localized high humidity• It would take a very long time to significantly

affect the structure• Mold is a possibility but structural damage is

much less probable

Rot in the AtticRot in the Attic

• This is a real concern

• The ventilation system usually discharges the hot, moist air into the attic

• In cold climates this means extensive condensation on the roof decking

MoldMold

• Will there be mold?– Mold is a possibility from the high humidity

environment– Surface mold most common and is often

visible (surface of walls, attic etc.)– It is possible to have mold where you can’t

see it – inside the walls.

Signs It Was a Grow HouseSigns It Was a Grow House

• Signs of a police bust– Forced front door

• Evidence of electric meter tampering

• Holes in the electrical service conduit

• Lots of unused knock-outs in electrical panel

• Large foundation hole

Signs It Was a Grow HouseSigns It Was a Grow House

• Concrete floor in basement painted white

• Basement foundation walls painted white

• Screw holes and patches in the foundation– Grow op equipment often mounted on wall

• Unusual modifications to plumbing– Multiple taps into water supply to feed plants

• Holes in sub floor / ceiling from ducting

• Unusual corrosion

Does it really damageDoes it really damagethe house?the house?

• Maybe not– Organized crime – sophisticated operation– Grow house electrical may be a completely

separate system. The household distribution wiring may never have been used

– No significant structural damage from foundation holes

– Humidity controlled with ventilation so little or no mold growth

– In this case, remediation primarily cosmetic– May have to replace underground electrical

service cable

Does it really damageDoes it really damagethe house?the house?

• Maybe– Amateur operation– Inappropriate and dangerous modifications to

existing home systems such as electrical panel

– Cut floor joists for ducting– High humidity levels not controlled

• Condensation damage to window frames• Condensation damage inside exterior walls• Mold growth on surfaces or inside walls

– Extensive cosmetic damage

Rot In AtticRot In Attic

• Ventilation systems often discharge into the attic to avoid detection– Damp stale air

• Condensation can cause rot to roof decking

• In serious cases the shingles and roof decking may have to be replaced

InspectionInspection

• A home inspector can recognize visible signs of unusual modification to or usage of systems– Excessive tapping into an electrical panel

(large knockouts unused)– Large foundation holes that have been filled in– Signs of overheated wiring in main electrical

panel– Structural damage

• Floor joists• Attic framing and roof decking

Mold InspectionMold Inspection

• Visible mold– Basement walls– Surface mold on drywall– Surface mold in attic

• Often ventilation systems discharge stale (moist) air into the attic rather than outside to avoid detection

• Discoloration / rot / mold in attic may be visible on underside of roof decking

InspectionInspection

• A home inspector cannot recognize or evaluate– Damage to buried electrical service main– Condensation damage and mold inside walls

• Destructive testing required (need to cut some holes)

– Structural damage that may have been finished over

Shots From A Major BustShots From A Major Bust

Grow HousesGrow Houses

Pillar To Post

Gary Bostock

Call 905 568 8202