Inspecting A Duplex & What You Should Be Looking For


Most buyers will want to conduct an inspection prior to purchasing a duplex or investment property. Anyone that isn’t an experienced buyer or a contractor with major experience would be crazy to purchase a duplex or investment property without doing their due diligence and having an inspection of the property done by a professional inspector.

Here’s where it gets a little tricky: where do you stop when it comes to doing an inspection?

I would make the answer dependent upon two things:

  1. What You See with Your Own Inspection (When You are Viewing the Property with a Realtor)
  2. How Deep Your Savings Account Is

Let’s focus on the first one: what you see in your own inspection of the property. This is where you and your realtor should be looking for tell-tale signs that there may be problems looming. It’s also where you might want to enlist further help than just a standard inspector.

You see, most home inspectors do general inspections – they’re looking for large problems. Many of the more specific issues are outside of their scope of expertise and require an expert in that specific field to tell you if you have a problem or not and to what degree of an issue it is.

Here’s what I would look for:

1 - The Roof

Are there any shingle fragments lying in the yard or any loose shingles on the roof?

Compare the subject roof with others and check to see how the spacing of each shingle compares to the other roofs. The older a roof is, the more likely the shingles are to have large gaps in between them. Older shingles also become curled and not perfectly flat like they are on a new roof. If you see any of these signs you may want to have a roofer inspect the roof.

A new roof could run you anywhere from $6k to $20k on a duplex or triplex. It’s worth safeguarding your purchase and most roofers will offer an opinion for free.

2 -  HVAC

There is a reason why I focus on the items that I give, and it is because you usually can’t hold off on buying any of these items if they stop working. HVAC is no exception.

Your furnaces and air conditioning units are certainly at the top of the “must work” list.

Three tricks that I use to tell if the current owner is maintaining the units are to check the furnace filter on a forced air furnace. You will often see with rental units that the owner doesn’t change the filter. This forces the furnace to work harder and often shortens its life-span.

If you are looking at a boiler, look at the water pressure. Boilers that are neglected or are at the end of their life-cycle often have low pressure.

The third thing I would look for is rust on the outside of the furnace. If the outside is heavily rusted the inside is likely to have rust as well, which will often end its safe use.  Furnace replacement is often in the $3k range and boilers often run $5k or more. Central AC units are $2-4k.

3 - Electrical & Plumbing

These two items are often something that can be band-aided, but at times they may need to be addressed immediately. I lump them together because you will often find that they are usually in the same state of disrepair or both in great shape (when people renovate they often do both electrical and plumbing updates at the same time).

Take a look at the electrical boxes. If you see fuses you will likely need to replace them. With plumbing, look for the type of plumbing that is used. If you see galvanized plumbing, you will likely have an issue with water pressure and will have to replace it at some point.

4 - Windows

Take a look at each window. Open and shut them to make sure they work. You may find that several of them are in poor condition. I have found that windows are about $300-$500 each.

5 - Siding

Look for rotting siding. Press a car key against areas you think may be rotted. You will usually see issues on the siding closest to the ground.

6 - Plumbing Waste & Supply Lines

One final thing to note are the plumbing lines coming into and leaving the duplex. If the property is older than 40 years, I would definitely have the waste-line checked.

You can generally see whether the incoming supply line is galvanized or if it is copper (you want copper). The waste-line isn’t something you can see. However, it may be the most important extra inspection you have conducted. The cost to replace this line is $8-$10k and when it fails it requires immediate attention. The cost of doing the extra inspection is $160 and well worth it.

7 - Radon

I am seeing more and more buyers conduct Radon tests. It has become popular in the past three years, and about 40% of the properties that I have seen testing done on has come back at a high level that requires remediation.

Radon is a gas that comes into a building from the basement and has been known to cause cancer. The cost of doing a Radon test is under $200.

8 - Lead-Based Paint

Lead-Based paint testing is done when an investor or owner-occupant is concerned that lead may be present in the property. If a person, mainly children, ingest paint chips or dust they can suffer from major health issues and learning disabilities.

The test for this is under $50. You will find that almost every duplex or fourplex in St. Paul and Minneapolis has lead-based paint somewhere in the building.  Before it was found to be harmful, lead was advertised on cans of paint like it was a great thing, kind of like smoking was good for your lungs.

9 - Mold

A final concern in any property in Minnesota is Mold. I know I am going Cliff Clavin on you, but Mold is a lot more complex than most people realize.

There are 209 known types of mold that exist. I have seen a lot of people say “that’s mold” or “that’s black mold”.

You really won’t know the specifics until you test it. Mold testing is done by testing the outside air and then comparing it to a sample that is taken from the inside.

As you can see, there are a lot of additional tests that can be conducted on an investment property. It is good to know, prior to making an offer, which of these tests you will conduct and who will be doing the testing.

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