Interior Staircase to Basement vs. New kitchen

11 Replies

Hey Guys and Gals.  I've been following the biggerpockets' forums for a while and have just purchased a duplex.  I plan to write up my new member story soon, but in the mean time, I need some help with renovation decisions.  So the current status of one side of the duplex is a 2br/1ba with kitchen and laundry on the main floor.  There is a basement underneath that is quite large and completely empty.  However, the basement only has an exterior entrance/exit.  I plan to renovate the basement to add two more rooms and rent each room individually.  My question is this, which of the following is the best option?

1.) Add interior stairs from main floor to basement.  This would allow all four tenants to use the kitchen/washer/dryer on the main floor.

2.) Add kitchen/laundry to basement so that the tenants in basement have their own kitchen/washer/dryer.

If anyone has insight on which would cost more, be an easier DIY, etc... I'm all ears!

*Basement has bare walls currently and plan to install a bathroom regardless.



@Prenn Tran , I have no experience in this area at all so it is more of a a guess. The main basis of how you will use the property should probably be your controlling decision factor. If you will only rent each bedroom separately then just put in an interior stairwell. If you plan in the future to make it a duplex then don't put the staircase in, just add a bathroom and kitchen downstairs. if you plan to exit by selling it as a SFR definitely put in the interior stairway. Invest the way you plan to use it.

Judging based off of strictly cost, more kitchens=more money. Stairs can be very costly if added since the live load of the structure has to be altered. Meaning additional load bearing beams/walls will need to be added to make up the difference for the hole cut in the floor ( if I understood you correctly).

One question you should answer yourself is, which format works for your area. Are there other rentals in your area with common area spaces(renting to college students?).

Kitchens require plumbers and electricians which are 2 of the most costly( at least in my area) to hire for work. Additionally cabinets can be quite expensive as well.

I don’t think adding stairs is a cheap option either since altering the structural integrity of the subfloor should require a skilled carpenter and permits.

Just my 2 cents, I would separate upstairs and downs stairs completely.

@Jerry W. Thanks for the input. I have no intentions to sell this property and the current market is great for renting each room individually. It’s already a duplex with the other side fully rented out. I asked the county if they would allow turning the basement into another separate unit to qualify for triplex but they said no.

So I probably am leaning towards just adding stairs and basement bathroom then.

I agree with @Addison Estes that adding the interior stairs probably needs a permit and a carpenter, at least for the rough work.

Adding the sewer pipes for the bathroom downstairs is probably going to involve either breaking up the floor with a jack hammer to add new sewer pipes, or building up a wood floor in the bathroom so there is room between the wood floor and the concrete for the pipes.  The jack hammer idea lets the toilet sit on the concrete floor, which is easier for access, and probably better if you don't already have 8' ceilings in the basement; the built-up floor idea means there is a step up into the bathroom, which will make the ceiling seem lower.

If you are committed to the downstairs bathroom idea, and you decide to jack hammer the floor, it probably won't be that much extra work to jack hammer it some more to add the sewer pipes for a kitchen down there.

Some other ideas:

Will there be two ways out of the new rooms downstairs?  You might have to install egress windows for the new rooms.  Or, if there is a window there now that would qualify as an egress window, you might not be able to block that window off with your proposed new stairs.

Have you thought about how you will split up the water / electric / other utilities for the new rooms downstairs?

I hope this helps!

Matt R.

@Matt R. and @Addison Estes , thanks for the feedback!  The renters are all young working professionals and there are a bunch of other properties that rent per room.  Currently, the other side of my duplex has 3 rooms and they are all rented out individually.

I think the bathroom downstairs will be a necessity since 4 bedrooms and 1 bathroom doesn't seem very ideal.  I haven't really thought of raising the floor in the bathroom to support the plumbing.  My plan was to tear up the concrete and rough in the plumbing that way.

There are a few windows in the basement that already exist so I'm covered there with respect to egress windows.  

Lastly, I'm planning to rent the rooms with all the utilities included in the price so that I wouldn't have to split up the basement rooms from the main floor rooms.  

My mind keeps switching back and forth from either the stairs, or installing kitchen.  I don't have a 100% feeling on either just yet:/

If you put a kitchen in it will be essentially changing the duplex to a triple, check that zoning allows. If you are doing a bathrroom anyway and zoning allows the conversion do it. Running plumbing is the biggest extra expense. 3 units will get you a better return in the long run.

Zoning does not allow triplex. If I renovated a kitchen, I believe it would still be considered a basement that just has a bathroom and kitchen.

I don't know your local regulations or the exact configuration of the basement, but the legalities of having bedrooms in basements can be very tricky. Here, a basement needs to be 50% above ground and have 2 exits to be "habitable". As for the plumbing problem, if your sewer pipe is above the level of the basement floor you can avoid breaking slab by getting a toilet that has a built in macerator and pump . You can have the sink and shower drain into toilet sump.

Before you decide what to do you had better do more research into what is involved with the building department to be able to use the basement as a living space. You can not just put up walls and call it a bedroom. Your insurance will likely get canceled if they find out..

In areas around here a new basement kitchen would not be permited although many older homes have them. In the arrangement you are talking about I had one town inspector not even want to see a refrigerator in the basement however most will allow the fridge but not a stove. You may have more limited choices then you think so see what town regs are.

All good advice, seems like I need to double check what is and isn’t allowed first. I called them to see if I can turn it into a triplex and that is definitely not allowed. I guess my next step is to see if I can make it a living space with rooms. Thanks all!

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