converting sfr into duplex - Posted by JR-IN

Posted by John Merchant on March 19, 2003 at 12:09:36:

Frank’s very right, but I’m NOT advocating the illegal sub-rental unit! Just pointing out they do exist in vast numbers…and hey, if it’s already there, why not use it?

converting sfr into duplex - Posted by JR-IN

Posted by JR-IN on March 17, 2003 at 17:44:08:

Does anyone have any experience in converting sfrs into duplexes? If so, what is involved in the process, including getting the correct zoning, and making sure the conversion is done correctly? Are there any resources for this type of procedure?


How about converting duplex into SFH… - Posted by David Krulac

Posted by David Krulac on March 19, 2003 at 17:32:22:

Yea, saw two such examples in the last couple of years. One was a victorian with 2 units, one up and one down. Originally a SFH, it was probably coverted to 2 units in 60s. Owner put it up for sale as duplex at a price that while FMV for a duplex was low for a SFH victorian. A couple bought it and proceeded to restore into a SFH.

But getting back to your original question. Sometimes the legal hoops are pretty tough and there could be zoning issues that you just can’t meet. Around here some of the deal killers are:

  1. off street parking usually 2 spaces per unit.
  2. basement units don’t meet fire code for egress
  3. 3rd floor units don’t meet fire code without a metal fire escape.
  4. lot vegatation cover soemtimes 30 to 50% of lot
  5. building coverage of lot sometimes max at 25 to 50%
  6. limitation on impermiable coverage of lot.

Your mileage will vary,

David Krulac
Central Pennsylvania

Lots of dupexes NOT legal - Posted by John Merchant

Posted by John Merchant on March 19, 2003 at 08:57:31:

When I first moved to Seattle area I was amazed to hear and learn of the jillions of illegal, never permitted, duplexes in Seattle area. I suppose a number of years back, when the NW was pretty sleepy and sluggish of economy (When the last person leaves Seattle, please turn out the lights!) there just wasn’t much care or concern about this at City Hall.

Result is today, tons of normal appearing SFR’s in Seattle area have mother-in-law units, with kitchens; one very nice home I saw in King County’s very prosperous E. Side, had 3 such units, and with today’s rents, is probably bringing in $4500 per month in rent!

Re: converting sfr into duplex - Posted by Don Dion

Posted by Don Dion on March 19, 2003 at 02:16:01:

This one is a question for your city or country building department. The laws vary to widely from area to area.

Re: converting sfr into duplex - Posted by Frank Chin

Posted by Frank Chin on March 18, 2003 at 07:39:38:


What’s involved depends on the area where you live.

Every municipality has a zoning board that rules on these matters. In most areas, including mine, ie NYC, what you have to do is get a variance.

The first issue is whether this is even possible.

Because most SFH are built in zones built for SFH, you wouldn’t even be allowed. So I suggest you check with your local building dept to see what the area is zoned for first.

Assuming conversion is allowed, i.e, the area allows one to two families, then you’ll have to get permits and file building plans. Since this requires the services of an architect anyway, check the phone books under expeditor. Expeditors are those who gets papework done in municipal and town agencies, and can recommend architects, which you’ll need for a such a variance. Many expeditors are not architects, but those who are both can:

a- Advise you of zoning issues.

b- File for permits.

c- Advise you of building code difference between SFH and 2FH if any. For instance, in NYC, to convert from 2FH to 3FH, and meet code, I have to install fire escapes, brick walls around furnace rooms. These are not required of 2FH which follows the code of SFH.

d- Draft and file revised building plans.

e- Prepare you and attend the zoning variance hearings.

Here in Nassau County where I own rentals, prior to a variance hearing, a letter goes to all the neighbors, as I recall, a block or two radius so they can go to the hearing and voice any objections. The town planning dept may also be involved. These folks would be concerned with:

a- Traffic in the area.

b- Character of the area.

c- Parking in the area. In other words, are there enough parking for two sets of tenants without your tenants parking cars in front of a neighbors house.

d- The town may object since granting variances for one can open the gates for more, and the question is whether the school system is at or above capacity. So if there’s already too many students, and the school operates in shifts, there will be objections here.

e- Water and sewer can be an issues. If the system is at capacity, the town may object on the grounds that it will overwhelm municipal services. If a septic system is involved, it may have to be upgraded.

Here in the metro NYC area, the NIMBY syndrone is such that neighbors will always object on traffic, parking, character of the neighborhood issues, and bring the local councilman to yell and scream.

So, that basically is what’s involved here. It may be simpler in your area.

Frank Chin

The trick is … - Posted by Frank Chin

Posted by Frank Chin on March 19, 2003 at 11:24:08:

1- to make sure tenants don’t park their cars in front of your neighbors home. In other words don’t rent to two familes with 4 cars each.
2- Keep the grass mowed and sidewalk clean.
3- Tenants don’t have noisy parties.

Then, you’re 95% certain the neighbors won’t turn you in. Of the above, number 1 ticks off neighbors the most.

Frank Chin