Q re industrial roof construction circa 1980

I'm going to buy an industrial / warehouse building to house my personal shop and generate some income via indoor car storage. I looked at one building which checks a lot of boxes for me, but of course there are some issues. It most recently housed a pot grow op, and the humidity led to some mold which will have to be dealt with.

What concerns me more than the mold, though, is that the inside of the roof has some kind of paper that is hanging down in sheets, and I don't know what it is or how important / dangerous / etc this condition is. I'm guessing this material is OE to the building, as there are some newer looking areas that have corrugated steel rather than whatever that peeling E36 M3 is (to me, from floor level looking up, it looks like drywall that the paper is falling off of).

so, I ask the hive, WTF? Pix:

Insulation backer sheet?

A lot of metal buildings have insulation in huge wide batts installed on the exterior of the red iron frame BEFORE the exterior sheet metal is added.  This insulation has a backer sheet (or bag) on it. It can deteriorate over time.

If that's what it is, the backer layer is not a crisis.  The good news is you've got a (partially) insulated building.  However the moisture issue could be a problem because the backer layer protects the fiberglass batt insulation from the moisture. If the backer layer was deteriorated and the insulation is saturated, the insulation would need to be replaced (assuming no rust issues to the metal cladding).  Insulation can be tricky on a metal building. 

In reply to SV reX :

Good luck!  I know how long you've wanted something like this!

Thanks Paul, I was hoping you'd chime in. The property description says "Roof: Flat, rubber membrane 2-3 years old, with sufficient drainage." I used to drive past this building every day when I lived in the next town over. Prior to being a grow op, it was a warehouse for Aurora Caskets, and before that it was a furniture restoration shop. 

Can you find out what is the material behind (above) the paper?

Regardless, this is too big of a purchase to go in guessing. I know a roof and building enclosure consultant (in Bloomfield Hills) that is a P.E. - if you want a contact to check this out. I'm sure he could do a PPI for a fee. PM me. 

Building is cinderblock, exterior walls appear sound, no big cracking or anything suggesting the ground isn't stable, etc. front "half" is 110' wide x 60' deep, with 2 overhead doors. Rear "half" is 130' wide x 60' deep, with another overhead door on the bump-out. Concrete floor is in nice shape. Windows are too big and too low for my liking. I'm thinking they should be replaced with glass block, or at least have some frosting applied.

It is located about 20 minutes from my house.

Old metal barn out back is good enough for storing groundskeeping stuff, but is nowhere close to airtight and the concrete pad is crap.

Property across the street is a horse training facility. There's a big harness racing track not too far away.

In reply to AngryCorvair (Forum Supporter) :

Since I commuted from Dexter to Plymouth via Territorial for a decade, I recognize this building. I spent 16 years working in a plant and spent far too much money and time on roof maintenance that had been put off for too long. Do you know what is under the membrane and above the decking? If there's rigid insulation that would be nice to have. An infrared camera scan might be worthwhile to see if there are wet areas, although you say the membrane is pretty new. Walk the entire building and carefully inspect the decking from below. If the roof was neglected in the past and water got through the membrane, it can cause rust through on the deck. It's rained hard the last few hours, could you get in there today to see if there's any leaking? Otherwise, good luck with the project.

Edit: Can you get to see any utility bills for the place? I'd want a rough idea of the heating bill.

DeadSkunk (Warren) said:

In reply to AngryCorvair (Forum Supporter) :

Do you know what is under the membrane and above the decking? If there's rigid insulation that would be nice to have. An infrared camera scan might be worthwhile to see if there are wet areas, although you say the membrane is pretty new. Walk the entire building and carefully inspect the decking from below. If the roof was neglected in the past and water got through the membrane, it can cause rust through on the deck. It's rained hard the last few hours, could you get in there today to see if there's any leaking? Otherwise, good luck with the project.

I do not know for sure, but it might be easy to see the cross-section where the roof drains come through. I did my first walk-through the day after two days of rain and only saw one spot on the floor, which was almost directly under one of the roof drains. There was one place where one of the ceiling boards had a hole in it (maybe 4" diameter total damage area), but there was no evidence of recent wetness in that area.

You shouldn't be short of lighting wiring if they were running a grow-op....

Hey! I know where that is also; I don't even live nearby. 

That's a good looking building. 
 

Warren's idea of hiring an infrared is a good idea. 
 

14,000 SF 20 minutes from your house is hard to beat!

That looks like paper backing used on polyiso foam board. I've only seen it used above the roof structure in 4'x4' pieces or 4'x8" though.

Count me in for a client when you are ready dude!

In reply to AngryCorvair (Forum Supporter) :

I went and looked at the real estate ad photos. I'd want to have a look at the two discoloured areas on the roof membrane, just to be sure. If you think I'm going on about the roof, I am because it's the most costly system in the building.  Paul will have current numbers, but I'll throw out a number of $150,000 for a full replacement. It needs to be treated with care and routine maintenance.

In reply to AngryCorvair (Forum Supporter) :

Not an architect, commercial HVAC so have been on the roof of a building or three.  That appears to be a gypsum panel roof, those were a thing in the late 1950's - early 1960's.   About 2 inches thick and apparently met code at that point in time for supporting the roof load over the span of the bar joists (4 feet?)  I think the panels had a sheet metal frame around the perimeter to hold the gypsum.   So yeah, basically a 2" thick sheet rock roof in those areas.  It's fine if you have an intact roof membrane above and don't plan on putting any additional weight on it.

I can't help you with your roof, but (from the third photo) it does look like the conduit guy knew what he was doing, so if his workmanship was representative of the standard everybody had to meet, that would be nice.

Can I just say, What a weird place for a casket warehouse.

A buddy of mine sells commercial roofing and building components in MI. If you want me to reach out to him about a good contractor, you know how to reach me.  

DeadSkunk (Warren) said:

You shouldn't be short of lighting wiring if they were running a grow-op....

We bought a house a few years ago where the realtor wasn't happy to have to disclose that the garage was turned into a grow room.

220......on every wall and the freaking ceiling. Yeah, that was nice along with the ridiculous level of insulation 

jgrewe said:

That looks like paper backing used on polyiso foam board. I've only seen it used above the roof structure in 4'x4' pieces or 4'x8" though.

Thinking the same thing but it does not compute if there is no roof deck underneath. It is unfamiliar to me but the other suggestion (above ) about some kind of 2" thick panel makes more sense. 

In reply to AngryCorvair (Forum Supporter) :

Playing around with Google maps brings me to this photo.  What sticks out to me is low door openings and thereby what could be a low roof.  The Sprinter barely fits.  And, if you get the Sprinter in the building, it seems you're not gonna get the Sprinter on a lift.  Is this tall enough for a lift?  Many lifts like double stack storage lifts?  
Are the door openings large enough to facilitate a business of Camper, RV, trailer boat storage?  

From a commercial warehouse perspective, what makes it cheap is small doors (can't drive in a box truck or larger.)  Also, no semi dock for typical manufacturing shipping and receiving.  Just keep these things in mind.  It should therefore be cheaper than other possible choices.  If it is not priced cheaper...it should be, so offer accordingly.  These might not be options or features that you need but they are options and features that will make it harder to sell if you need/want to.  

In reply to John Welsh :

You picked a weird feature for sure. See how the pavement goes uphill toward the door? The floor slopes down inside that door, I have no idea why. Maybe it was originally a dock that they filled in?

In reply to AngryCorvair (Forum Supporter) :

Is this Wayne County or Washtenaw?  

I ask because most counties have property records searches online.  Many also give annual aerial photos which might give insight to if that was a previous loading dock.  

The listing says that the property is on a well and septic.  No water bill, no sewer bill?  Seems great but is it likely to remain that way?  If water/sewer service comes down your road, you may be required to foot the bill to get tapped into the water/sewer.  Any knowledge or insight to if those services are coming?  

I'm not trying to dissuade, rather I am just trying to look for what might be overlooked.  

AngryCorvair (Forum Supporter) said:

In reply to John Welsh :

You picked a weird feature for sure. See how the pavement goes uphill toward the door? The floor slopes down inside that door, I have no idea why. Maybe it was originally a dock that they filled in?

IIRC, that door on the left was a loading dock and they filled it in at some point in the last 24 years.

In reply to AngryCorvair (Forum Supporter) :

When I saw the pictures I hoped you were going to say the racetrack was part of the property you're going to buy.  

I'm not familiar with whatever is hanging from the ceiling so I can't help there.  The one thing I would say is if you're going to rent space for vehicle storage the building needs to be 100% dry inside, and if people see those sheets hanging down they're going to be hesitant about storing their car there.

DeadSkunk (Warren) said:

AngryCorvair (Forum Supporter) said:

In reply to John Welsh :

You picked a weird feature for sure. See how the pavement goes uphill toward the door? The floor slopes down inside that door, I have no idea why. Maybe it was originally a dock that they filled in?

IIRC, that door on the left was a loading dock and they filled it in at some point in the last 24 years.

I wonder why they did that. I often dream about having a warehouse/shop and I'd want to have both options: drive-in door as well as a loading dock door that should make truck deliveries easier. 

Good luck!  Hopefully it all works out!