• Welcome to the new and improved Building Code Forum. We appreciate you being here and hope that you are getting the information that you need concerning all codes of the building trades. This is a free forum to the public due to the generosity of the Sawhorses, Corporate Supporters and Supporters who have upgraded their accounts. If you would like to have improved access to the forum please upgrade to Sawhorse by first logging in then clicking here: Upgrades

Accesory Dwelling Units

N

NH09

Silver Member
Joined
Sep 11, 2010
Messages
153
Location
New Hampshire
Does anyone out there have regulations regarding Accesory Dwelling Units (in law apartments)? I am curious to see if anyone has an ordinance that actually works. We have a local ordinance and it is very difficult to enforce when denied by the Zoning Board of Adjustment. I have copied the section below for everyones reading enjoyment:

02.6 ACCESSORY DWELLING UNITS (2008) (allowed by special exception)

A.In all cases involving an Accessory Dwelling Unit (ADU), the Board of Adjustment in addition to the criteria contained herein shall consider the following requirements:

1.The primary dwelling unit shall be owner occupied.

2.The ADU must be developed in a manner which does not alter the character or appearance of the principal use as a single-family residence.

3.The ADU is intended to be secondary and accessory to a principal single-family dwelling unit.

4.The ADU shall not impair the residential character of the premises nor impair the reasonable use, enjoyment and value of other property in the neighborhood.

5.Only one ADU shall be allowed per a property.

6.The ADU shall not exceed 700 SF total space.

7.The ADU shall include no more than one bedroom.

8.Adequate off-street parking must be provided.

9.No additional curb cuts shall be allowed.

10. Any necessary additional entrances or exits shall be located to the side or rear of the building whenever possible.

11. Attached accessory dwelling units shall be designed to allow for re-incorporation into the principal dwelling unit.

12. Attached accessory dwelling units shall have and maintain at least one common interior access between the principal dwelling structure and the accessory dwelling unit.

13. An ADU shall be located in an existing or proposed single-family home or detached accessory structure.

14. All criteria of the zoning district including lot sizes, frontages, yard requirements and height requirements must be met.

15. An existing nonconforming residential use shall not be made more nonconforming.

16. An ADU must meet all current local and State Building, Fire and Health Safety Codes.
 
We do not allow them, yet...

K. BUILDINGS ON A ZONING LOT. Every building hereafter erected or structurallyaltered to provide dwelling units shall be located on a zoning lot as herein defined and in no

​
case shall there be more than one such principal building on one zoning lot.

 
The interesting thing is that they can be attached or detached although all of the ones I have dealt with have been in the primary residence (basement, room over garage, etc.). The intention is that it is somewhere in between a 1 and 2 family, but it does not fall within the building code because it is still technically a one family. I have not heard of these Acessory Dwelling Unit regulations outside of New Hampshire and was wondering if anyone else around the country had a similar ordinance.
 
NH09 said:
The interesting thing is that they can be attached or detached although all of the ones I have dealt with have been in the primary residence (basement, room over garage, etc.). The intention is that it is somewhere in between a 1 and 2 family, but it does not fall within the building code because it is still technically a one family. I have not heard of these Acessory Dwelling Unit regulations outside of New Hampshire and was wondering if anyone else around the country had a similar ordinance.
Click to expand...
Usually, they are regulated through zoning district provisions. What you have isn't really a regulation, it's an outline for a report to a commission. There's very little which is objective and a great deal which is simply a matter of opinion. And if it has two dwellings, then under the building code it is two-family dwelling. I suggest poking around on Municode.
 
Both city and county here handle it through the planning department. Around here the second dwelling is referred to as a 'granny flat'. You can build one on your property in the city if it doesn't exceed the 40% coverage limit of the lot for all buildings. County you need to have a minimum of 15 acres before you can add a second dwelling unit. I think in both cases you need to start with planning and get the approval to build on the lot.
 
Agreed brudgers, I feel that it is either a one family or a two family. If someone is renting and apartment in their house then it is a two family and must comply with all applicable zoning and building codes. Otherwise if someone has family living with them, and it is not truly an "apartment", then the town has no business regulating them. The tough thing will be to convince the members of the planning board that this ordinance is unnecessary and unenforcable.
 
We currently do not allow accessory buildings to be lived in. I think the 02.6 above is pretty well written because it includes some controls & alternatives, except utility connections (from primary structure or new hookups?) aren't mentioned.
 
Here, they are allowed and regulated by the planning dept. I am at home and don't have a copy of the requirements, but I do know that a kitchen is not allowed. They almost always become rentals.
 
There would be no separation of utilities required, and a kitchen is optional. I think the term "Accessory Dwelling Unit" may be confusing, as most of these units are inside the primary dwelling. The ordinance does allow for a detached ADU (haven't seen one yet), but it would have to be under 700 square feet and have a bath and kitchen.
 
NH09 said:
Agreed brudgers, I feel that it is either a one family or a two family. If someone is renting and apartment in their house then it is a two family and must comply with all applicable zoning and building codes. Otherwise if someone has family living with them, and it is not truly an "apartment", then the town has no business regulating them. The tough thing will be to convince the members of the planning board that this ordinance is unnecessary and unenforcable.
Click to expand...
The mistake here is to attempt to regulate who uses the accessory dwelling apartment. Whether it is rented or "given", to a relative or to a stranger, all is unimportant to the building code as a practical matter impossible to enforce (except for in cases of neighbor compliant with documentation). A two family dwelling has two independent spaces each with cooking, bathing and sleeping areas, and so any structure with two complete dwelling units is a two-family dwelling structure. Having just said that, the term "accessory" to a SFD for us, means we review for codes as a SFD if the accessory apartment falls within our s.f. and other zoning limitations
 
Our rules are very similar to what the OP listed.

Accessory apartments are addressed through the Planning Board, and local law sets specific standards for review (ie the requirements listed by the OP). The PB cannot approve the application unless the minimum standards are met. They also address other issues, such as impact on the neighborhood, available parking, etc.

We do not permit them in accessory structures.
 
We allow either attached or detached, 1000 sq ft max, one bathroom only, kitchen ok, has to use same utilities and same address as main residence (including same septic if applicable). Owner signs a recorded document that states accessory dwelling will not be rented, which is virtually impossible to enforce. All neighbors are notified and have a say before approval is given.
 
NH09 said:
Agreed brudgers, I feel that it is either a one family or a two family. If someone is renting and apartment in their house then it is a two family and must comply with all applicable zoning and building codes. Otherwise if someone has family living with them, and it is not truly an "apartment", then the town has no business regulating them. The tough thing will be to convince the members of the planning board that this ordinance is unnecessary and unenforcable.
Click to expand...
It's an apartment and a second dwelling unit whether they rent it or have a family member living in it...or even if it is empty.
 
there is case law in support of the position that a single family building can have two kitchens and yet not be a two family dwelling. a kitchen does not make an ADU.

in-law suites/nanny suites can exist but they must be connected to the primary dwelling - no completely independent entrances.

as soon as there is separation, it is classified as a two-family.
 
Thanks Mr. Softy - although the town considers anything with a second kitchen an ADU, there is nothing in the building code (or our zoning ordinance for that matter) that restricts a single family dwelling to one kitchen. Do you have any liks or information relating to that case?
 
In fact there are tens of thousands of two kitchen households used by kosher jews, , , it is a difficult question , , but having two independant dwelling units each with their own entrance (even from a shared foyer), cooking, sleeping and bathing function areas helps define it a little bit.
 
Our ordinance is similar up to about #12 then you took the left turn at Albuquerque. Our ordinance is enforced by the planning department. They actually flag some plans and require a final planning inspection before c.o. is issued and yes they check for second kitchens. I think is kosher comment from Yankee is very pertinent here. That is certainly not something that I had ever thought of.

I once turned down an electrical rough in for having a second range wire run to the basement. The wall was even marked "range" with paint. The boss told me that the building code did not regulate second kitchens and that planning had inspectors to regulate planning requirements.
 
This is what we use:

In-Law Suites

(1) In-law suites are permitted in R1 and Ru Zones subject to the following:

(a) In-law suites are not permitted in two family dwellings or in a dwelling which already incorporates an accessory dwelling unit;

(b) In-law suites are considered secondary uses and must meet all the zoning requirements for the zone in which they are located; and

© In-law suites are meant to be temporary units and at such time as they are no longer required, the unit is to be incorporated into the principal dwelling.

Accessory Dwelling Units

(1) Where permitted and unless stated otherwise in this By-law, accessory dwelling units shall:

(a) not result in more than two (2) dwelling units contained in any converted single detached dwelling, subject to the lot area being not less than five hundred forty (540) square meters;

(b) be secondary to the main dwelling unit, and not exceed seventy five (75) percent of the floor area of the basement;

© be completely self-contained and conform to the standards of the National Building Code of Canada as adopted by the Province of New Brunswick;

(d) require one (1) parking space, in addition to the normal requirement of the zone; and

(e) not permit a Commercial/Residential use (as per Section6.(X)), or Daycare Facility to be operated on the property.

The big sticking point is the "meant to be temporary" part. If I am doing a plan review and the only way to re-incorporate the in-law suite into the house is to undergo significant renovations then I call it an accessory dwelling unit. I'm not sure what the codes down there in the US require for fire separations between dwelling units, but here in Canada we need a 45min separation, so I err on the safe side so I can require the separation.
 
You must log in or register to reply here.
Top