BUILDING PERMIT FOR SMALL PREFAB MODULAR HOMES

The idea of tiny home living is not new. Over the last few years, tiny homes have been getting a lot of attention as a housing choice for people to live in or rent out.

Adding or building a tiny home to your property can sometimes be a challenge. Unlike the regular-sized houses we have been building for decades, tiny homes are an emerging trend. As such, getting successfully through approvals and meeting requirements to build a tiny home can be difficult. 

A small prefab modular home is a small, private and selfcontained dwelling unit:

With living and dining areas

With kitchen and bathroom facilities

With a sleeping area

Intended for year-round use.

A small prefab modular home can be a primary home or a separate building on a property that already has an existing house.

Small prefab modular homes include tiny home on wheels, site-built tiny home and shipping container tiny home.

Despite their size, small prefab modular homes must comply with the health and safety requirements of Ontario’s Building Code, municipal zoning and other local by-laws.

Small Prefab Modular Home Sizes

The size of a tiny home varies from municipality to municipality, depending on standards set out in zoning by-laws.

Some municipalities have minimum size requirements, while others have maximum size requirements. For example, some municipal by-laws require a tiny home to be 37 sq.m. (400 sq.ft.) or less.

In all cases, a tiny home cannot be smaller than the minimum required size set out in Ontario’s Building Code, which is 17.5 sq.m. (188 sq.ft.).

Build a Small Prefab Modular Home

Before deciding to add a small prefab modular home to a lot, it is important to discuss with the planning and building departments of the municipality. 

Types of Mini Prefab Modular Homes

Mini prefab modular homes come in many different shapes and sizes. Despite their size or uniqueness, mini prefab modular homes are required to meet the Ontario Building Code and the Zoning By-Laws.

Tiny Prefab Modular Homes Built On-site

Many tiny prefab modular homes, like regular-sized houses, are built on the site where they will be located. The construction requirements for this type of tiny prefab modular homes are the same as the requirements for building a full-sized single-detached house, but there are some design differences.

The differences involve the size of rooms and spaces, and if it will have more than one storey. Other design considerations include installing a heating, ventilation and airconditioning (HVAC) system that is appropriate for heating and cooling a smaller space. 

 Municipal planning and building departments will confirm whether a small prefab modular home planning and building departments could be added or built on a psrticular property and answer questions related to the Building Code, Zoning By-laws, site servicing and building permit application.

 Some of the important things to discuss with the municipality about as you consider building a tiny home include:

municipal zoning requirements that apply to your property

designing your tiny home to comply with the Building Code

getting necessary building permits

required building inspections during construction

parking requirements

size requirements for tiny homes, if any

rules about connecting to municipal services, if available.

Some lots will not work for a tiny home.

Local zoning by-laws may not permit adding a tiny home without further

municipal approval. 

The lot may be too small to meet setbacks or other local requirements without further municipal approval.

The lot may not have adequate access for emergency services such as firefighting and Emergency Medical Services.

A factory-built small prefab modular home must meet one of the two key CSA certification standards in the Building Code for factory-built buildings. These standards are:

CSA-Z240.2.1-09 Structural Requirements for Manufactured Homes

CAN/CAS – 2240 Series “Mobile Homes”

CSA A277-08 Procedure for Factory Certification of Buildings.

A small prefab modular hometiny home built to these standards will have a

label on the inside of the electrical panel indicating which certification it complies with.

Confirm that a factory-built small prefab modular home manufactured or purchased from a supplier outside Ontario meets Ontario’s Building Code. Just because it is sold in Ontario, it does not mean a factory-built small prefab modular home meets Ontario’s Building Code. It is very important to confirm that a factory-built small prefab modular home you purchase is appropriate for the weather and conditions of the municipalty you live in.

Do not buy a factory-built small prefab modular home that meets the

CAN/CSA-Z241 Series-03 Park Model Trailers standard if your plan is to live in it year-round. This is a standard that applies to seasonal buildings such as cottages. 

 The Ontario Building Code requires all buildings to be inspected during construction. In the case of factory-built buildings, quality control inspections and monitoring occur during the assembly of buildings and building components. A tiny home built off-site without CSA certification will likely not have had the appropriate inspections. This may become an issue as you apply for a building permit to locate your tiny home on your property. 

In Ontario, all new home builders must be registered with Tarion. Tarion maintains an Ontario Builder Directory of all new home builders. New home buyers are encouraged to check the Ontario Builder Directory to ensure their builder is registered with Tarion. Tarion’s website outlines the types of homes covered and not covered by their warranties and protections.

Just like a small prefab modular built on-site, a factory built small prefab modular home can be placed on footings or a foundation built according to the Ontario Building Code.

A factory built small prefab modular home can also be secured to its site by complying with the standard: CSA-Z240.10.1-08 “Site Preparation, Foundation and Anchorage of Manufactured Homes”.

Instead of building a full second storey to a small prefab modular home, another option is to build a loft or a partial second floor. The Ontario Building Code calls these spaces “mezzanines”. In a small prefab modular home a mezzzanine would consist of a raised floor area and are often intended as a sleeping space. 

The Ontario Building Code Requirements for Mezzanines:

If the mezzanine is open to below, then the size of the mezzanine cannot be

greater than 40% of the floor area of the small prefab modular home, and it must have a guard/handrail to prevent falls

If the mezzanine has walls all around it, then the size of the mezzanine cannot be greater than 10% of the small prefab modular home.

Mezzanine must have stairs, guards and handrails that meet the Ontario Building Code. 

Small prefab modular homes must have necessary servicing such as water and sanitary. Small prefab modular homes can have a variety of septic systems including grey water pits, compostable toilets, privy, etc. For more information on the different options please contact your municipality.

Municipal Zoning by-laws set out the kind of buildings that can be built, the sizes they can be and where they can be located on a property. As a result, Municipal Zoning by-laws may regulate whether a tiny home is permitted in a property. Contact local planning department about:

■ zoning by-laws that apply to the property

■ whether the zoning by-laws permit building a tiny home

■ avilable services to the property such as water, sewage and electricity

Even though tiny homes are small, they must still meet the local zoining by-laws. Complying with municipal by-laws is important so that you can build a tiny home if you choose to proceed.

Depending on where your tiny home is located (rural, suburban or urban areas), municipal zoning by-laws and standards will vary.

Zoning by-law requirements that could impact building your tiny home without further municipal permissions may include:

■ permitted land uses

■ minimum lot sizes

■ minimum size for residential buildings

■ minimum or maximum lot coverage by built structures

■ lot frontage and setback requirements from lot lines and the public street

■ massing and height requirements

■ parking requirements (including tandem parking)

Other requirements that could impact building your tiny home may include:

■ streetscape and architectural design

■ location of exits and entrances

■ appropriate municipal or private servicing (water, sewage, electricity etc.)

■ whether new residential development can occur in existing settlement areas

■ restrictions on lot severance

■ access for emergency services

Our team of civil engineers use advanced Building Information Modeling (BIM) tools to create 3D models of building structures and infrastructure systems. This enables us to optimize the design, construction, and operation of our projects.