Backyard design and build

Design and build means one contract covering the drawing and the construction, and for most Ottawa back gardens it is the right way to buy. The reason is sequencing. A back garden involves excavation, drainage, base preparation, masonry, carpentry, planting and electrical, and one party owning the whole sequence is worth paying for.

Before excavation. Request utility locates and follow the current instructions from Ontario Dig Authority, including any private-locate arrangements needed for your property. Confirm the locate package with the person performing the excavation before work starts.

Understand existing drainage before changing levels. Map the swales, downspouts and drainage outlets, and check the approved grading information where available. Discuss the proposed changes and any review requirements with the City before work; protect neighbouring properties and existing drainage routes.

Step three: excavation and base. The base is the part you never see and the only part that decides whether the work is still flat in ten years. On clay, expect a deeper excavation and a thicker granular base than a sandy site would need, with a geotextile separation layer between the clay and the stone so the two do not mix. Compaction in lifts, checked, is what keeps a patio level through the freeze and thaw cycle.

Discuss structural and ground conditions. Ask a qualified professional to assess the proposed dimensions, drainage, frost exposure and ground conditions. Confirm whether engineered drawings, guards or municipal approvals are needed; general web dimensions are not a design for your property.

Step five: planting, irrigation and lighting. Sleeves under any paving first, then soil preparation, then planting, then lighting. Soil is where most planting budgets go wrong: Ottawa clay subsoil is not a growing medium, and 300 to 450 mm of amended topsoil in beds is the difference between plants that establish and plants that sulk.

Discuss the schedule early. Ask about design revisions, approvals, material availability, access and weather-dependent work. Agree the sequence and any dependencies with the contractor before fixing dates.

What to include when comparing prices. Ask for excavation and disposal, base preparation, paving, planting, drainage and site restoration to be listed separately. Access, quantities and finish selections affect the scope. Confirm allowances, exclusions, taxes and how a change is priced before agreeing to work.

What makes an Ottawa back garden different. Access and clay. Inner-city lots in Hintonburg, the Glebe and Old Ottawa South are narrow, and a machine often cannot reach the back garden at all, so material moves by wheelbarrow through a 900 mm gate. Restricted access can affect labour and equipment costs; ask for an itemized, site-specific written quote. The clay is the other half: it drains slowly, it heaves, and it means deeper bases, geotextile and real drainage design. Add the salt line along the driveway and the front walk, and the plant list within three metres of any hard surface has to be salt tolerant.

Ask about qualifications and responsibilities. Request relevant experience, insurance information and the written scope. Ask which professional design input or approvals your project needs; verify any claimed professional title through the relevant official directory, such as the PEO directory. This site does not verify a contractor’s credentials.

What to ask before you hire. Has a locate been requested, and when does it expire. What is the excavation depth and base thickness, and is geotextile included. How is water leaving the site, and does anything discharge toward a neighbour. Is any wall over one metre, and who is the engineer. Can a machine reach the back garden, and if not, is hand excavation priced in. How much topsoil is going into the beds. What is the written warranty on settlement, on plants, and for how long. And is the price fixed or an allowance.