Accessory Apartment Construction Guide For Single Detached Dwelling and Semi-Detached Dwellings that have been in existence for at least five (5) years Notes: Buildings that are less than five (5) years old shall comply with Part 9 of the Ontario Building Code including spatial separations. This document is a guide for homeowners and does not cover all possible conditions. The illustrations are not intended to limit the ways by which compliance with By-law and Code requirements can be achieved. Details and requirements may vary depending on site and building conditions. Additional information may be required during the review of the building permit application. Refer to Zoning By-law and Ontario Building Code for accuracy. You may engage a qualified designer to prepare permit plans. Notwithstanding an approved building permit, the issuance of the permit does not constitute approval under the City s Residential Rental Unit Licensing By-law # 20-2008, as amended, Two-Unit House Registration By-law # 41-2001, as amended, Property Standards By-law # 01-2002 and the Ontario Fire Code. H:\forms\handouts\bldg049 1 of 11
General Requirements A Building Permit is required for alterations to existing basements except for: Replacement of floor finishes (carpet, tile, hardwood etc.) Installation of cabinetry where no plumbing alterations will occur Replacement of a window within the existing rough stud opening Note: A finished basement must comply with the building code and zoning requirements. For more information, contact The City of Oshawa s Building Department at 905-436-5658. General Zoning Restrictions: The property must be zoned R1, R2, R5, OSR-A, OS-ORM, AG-A, AG-B or AG-ORM and meet all of the minimum requirements as set out in the current Zoning By-law Properties that are located in the area depicted by Schedule H are not permitted to have accessory apartments Parking is required for both units as set out in the current Zoning By-law A minimum lot frontage of 11 metres A minimum of 50 percent of the front yard is to be landscaped Additional requirements apply for corner lots Application Requirements: Application and Schedule 1 Designer Information forms and two copies of the plans listed below. (Owner s Authorization will be required if applicant is different from property owner) Survey or site plan of the property showing dimensions of all existing buildings and structures, including dimensions to all property lines. Any addition or enlargement of windows is to be plotted on the site plan. (see sample site plan on page 5) Construction drawings including the floor plans of all levels outlining the existing layout, a detailed floor plan of the proposed layout, structural details if applicable, wall section and a legend with construction notes. Step-by-step instructions are located on page 4. Permit fee, payable at time of application, may be paid by cheque (made payable to The City of Oshawa), cash, debit, Visa, MasterCard or American Express General Building Code Requirements: Provide a minimum ceiling height of 6 feet 5 inches including areas under beams and ducts. Doors to rooms without dedicated return air inlets shall be under-cut. Each bedroom requires natural light equal to minimum 2.5% of the room s floor area. Living rooms and Dining rooms require natural light equal to minimum 5% of the room s floor area. No windows are permitted in walls closer than 4 feet to the property line, unless protected with a fire resistance rating of 45 minutes. Each finished room requires a minimum of 3 square feet of openable window area for natural ventilation except for bathrooms, which require 1 square foot. Rooms with mechanical ventilation may not require natural ventilation. A smoke alarm is required in each bedroom and each area/hallway serving bedrooms and may be battery operated. A carbon monoxide alarm is required adjacent to each sleeping area and may be battery operated or a plug in type. H:\forms\handouts\bldg049 2 of 11
Laundry facilities shall be provided in each dwelling unit or in a common laundry room that is accessible to both units. An existing furnace system can serve both dwelling units provided an inline smoke detector is installed in the supply or return air duct and upon activation will shut the fuel and electrical supply to the furnace. Clearances around furnaces and hot water appliances shall be maintained as per manufacturer s specifications and/or the Gas Code. A minimum 30-minute fire separation is required between the dwelling units, furnace room, common laundry room and shared exits. Shared exits that provide the only means of egress from a dwelling unit must have a minimum 30-minute fire separation and have hardwired and interconnected smoke alarms in both dwelling units and all common areas. An egress window will also be required. All structural walls, beams and columns shall be fire rated to the same level as the floor that they support. Additional requirements may be applicable depending on the configuration of the spaces. H:\forms\handouts\bldg049 3 of 11
Step by Step Instructions 1. Site Plan A site plan drawing is always required when creating a new unit. Refer to the Site Plan on page 5 and create your own containing all the dimensions and information as shown on the sample or modify a copy of your original survey. It is the responsibility of the owner(s) to provide accurate site information for building permit applications including dimensions, lot area and locations of property lines, easements, right of ways, etc. 2. Legend and Notes Refer to the Legend and Notes on page 6. Create your own, add to or modify the samples to provide the full scope of construction information for your project. 3. Existing Floor Plans Refer to the Existing Floor Plans on page 7. Create your own using the sample as a guide or provide the original house plans outlining the following information: The unaltered portion of the building may be shown in a simplified manner Show each floor level with all existing walls, doors, windows, cabinetry and room uses 4. Proposed Floor Plan Refer to the Proposed Floor Plan on page 8. Create your own using the sample as a guide and show all information listed below: Note the use and dimensions of each room or space including stair locations The location of new door and/or window openings, including their size and proposed wood and/or steel lintels The location, size, material and grade of proposed steel or wood beams used to replace existing load-bearing partitions and the supporting foundations Proposed and/or existing supply and return air diffuser locations Location and design of all new window wells, showing how trapped water is to be drained Clearly identify the locations and ratings of fire and sound separations between units 5. Elevations An elevation drawing is required when a new window or door opening is proposed. Refer to the Elevations on page 9. Create your own using the sample as a guide to show any alterations to any of the openings. Detail the elevation where a window or door area has been added or removed, showing total wall area from ground to underside of soffit and all the sizes of the new and existing windows in the wall. 6. Wall Section Refer to the Wall Section on page 10 and the Egress Window Requirements on page 11. Create your own or use the samples as part of your submission. Add proposed ceiling height information to complete the section. 7. Plumbing The name of Plumber and license number are to be provided for new or alterations to plumbing. Plumbing drawings prepared by a qualified designer or homeowner including sizes, connections, materials, etc., may be provided in lieu of a licensed plumber. H:\forms\handouts\bldg049 4 of 11
1. Site Plan Create your own using the sample below or modify a copy of your original survey. Include all the dimensions and information as shown on the sample below. Note 1: All measurements are in metric under Zoning By-law 60-94, as amended. All imperial measurements for any regulation such as (e.g.) lot area, lot frontage, setbacks, parking spaces, etc. must legally meet the metric measurement required when converted from imperial to metric. Note 2: Curb cut and/or a site alteration permit may be required for new parking spaces. For curb cuts contact Service Oshawa at 905-436-3311 and for site alteration permits contact Engineering Services at 905-436-3311 extension 2594. H:\forms\handouts\bldg049 5 of 11
2. Legend and Notes Create your own, add to or modify the samples below to provide the full scope of the construction information for your project. Example Construction Notes: (include on drawings) Exterior Walls See section drawing attached (sample on page 10 can be submitted) Interior Non-Load Bearing Walls New 2 inch x 4 inch wood studs at 16 inch on center separated from concrete with sill gasket New ½ inch drywall on both sides Optional sound insulation Ceiling Existing size & spacing of joists Resilient channel and 1 layer of 5/8 inch drywall Provide ceiling height under beams and under ducts in each room and at stairs (measure from leading edge of stairs to ceiling) H:\forms\handouts\bldg049 6 of 11
3. Existing Floor Plans Draw simple existing layout plans of all levels or provide a copy of the original house plans. See examples below. Figure 1 - Existing Basement Layout Figure 2 - Existing Main Floor Layout Modified Figure 3 - Existing Second Floor Layout H:\forms\handouts\bldg049 7 of 11
4. Proposed Floor Plan Provide a detailed plan of your new basement layout. See example below. Scale: 1 = H:\forms\handouts\bldg049 8 of 11
5. Elevations If a new window or door is proposed, provide a fully dimensioned elevation drawing outlining all the openings and their dimensions. Summarize the areas as indicated in the sample chart below. WEST ELEVATION Openings Building Face Area Window Area Door Area Include distance from property line Calculations Summary (21.5x32.33)+(20.33x13) = 960 square feet 2(3x4)+2(3.5x4)+(4.5x4)+(2.5x1.33)+(2.5x2.5) = 80 square feet (N/A) = 0 square feet 14 feet 7 inches H:\forms\handouts\bldg049 9 of 11
6. Wall Section Create your own or use the sample below as part of your submission. Add the proposed ceiling height information to complete the section. H:\forms\handouts\bldg049 10 of 11
6. Egress Window Requirements A basement containing bedrooms will require direct access to outdoors for escape in case of fire. If this is not possible then an egress window must be provided. The egress window shall have an unobstructed open portion having a minimum area of 3.8 square feet with no dimension less than 15 inches and is operable without the use of tools. When open, all window components must be self-supporting. The removal of the glass is not acceptable. Egress window wells require a minimum clearance of 22 inches (550 mm) in front of the window. (see drawing below) Note: Window wells must not encroach onto adjacent properties Foundation walls with new openings wider than 4.0 feet or walls having openings more than 25 percent of its length shall be considered laterally unsupported and may require an Engineer s review. Certain types of basement renovations that involve excavations may require approval from the City of Oshawa s Engineering Services Branch in conjunction with the Site Alteration By-law 85-2006. Ensure perforated drainpipe remains 6 inches above weeping tiles with gravel in between to act as a filter for the weepers. Additional information can be found in the TACBOC (Toronto Area Chief Building Officials Committee)standard details BO2a and BO2b. H:\forms\handouts\bldg049 11 of 11