D. Structures and Mechanisms · Form and Function

Designing Structures for People, Communities and the Environment

D1.1 D1 A3.3 A3.1 A1.5About 50 minutes

Learning goals

I can identify environmental, social and economic factors that should be considered when designing and building a structure.
I can evaluate design options using criteria, including the needs of individuals and communities.
I can explain why it is important to include community members, including First Nations, Métis and Inuit communities, in decisions about structures.

Words to know

environmental factor
Something about the natural world that a design affects or is affected by, like habitats, water, energy use or climate.

social factor
Something about people and communities, like safety, accessibility, culture, health and how people will use the structure.

economic factor
Something about money and resources, like the cost to build and maintain a structure, and the jobs it creates.

stakeholder
A person or group affected by a decision, such as neighbours, users, businesses or a nearby First Nation.

accessible
Able to be reached, entered and used by everyone, including people who use wheelchairs or have other disabilities.

trade-off
Giving up some of one thing to get more of another.

Hook: a new rink for the town

Your town wants to build a new outdoor rink with a roof. One group wants it in the park by the river. Another wants it next to the school. Some people worry about the cost. Others worry about the trees and the river. A nearby First Nation wants to know how the project will affect land and water that are important to them.

Building a structure is never only about forces and materials. Designers must think about environmental, social and economic factors too.

An outdoor skating rink under a large open-sided wooden roof in a snowy park beside a river, with a few skaters on the ice. — A roofed outdoor rink like this one has to balance cost, what the community needs, and its effects on nearby trees, river and land. AI-generated image

Environmental factors	Social factors	Economic factors
Will it harm habitats, wetlands, trees or wildlife?	Who will use it? Does it meet their needs?	How much will it cost to build?
How much energy will it use to build and run?	Is it safe and accessible for everyone?	How much will it cost to heat, repair and maintain for many years?
Where do the materials come from? Can they be reused or recycled?	How will it affect neighbours (noise, traffic, views)?	Who pays (taxes, fees, grants)?
Will it change how water drains or cause flooding?	Does it respect the culture, history and rights of the community, including First Nations, Métis and Inuit peoples?	Will it create jobs or help local businesses?
Is it designed for the local climate (snow, wind, permafrost)?	Did the community have a say?	Will it save money over time (e.g., by using less energy)?

Questions to ask when designing a structure

Good designs look for the overlap: a structure that works for the environment, for people and for the budget at the same time.

Meeting the needs of individuals and communities

A structure should serve the people who will use it.

Accessibility: ramps, elevators, wide doors, automatic doors, accessible washrooms and clear signs let people who use wheelchairs, walkers or strollers, and people with vision or hearing loss, use the space. Ontario has an accessibility law (the Accessibility for Ontarians with Disabilities Act) and building code rules for accessible design.
Different communities have different needs. An urban community may need a structure that handles crowds and traffic. A rural community may need one that serves people across a wide area. A remote northern community may need a design that can be built with materials brought in by winter road, barge or plane, and that works on permafrost.
Listening to stakeholders: good projects hold public meetings and surveys so people can share ideas and concerns.

First Nations, Métis and Inuit perspectives

First Nations, Métis and Inuit communities have deep knowledge of the land, water and wildlife where they live, built up over thousands of years. Many Indigenous peoples, including the Haudenosaunee, share a teaching that decisions should consider their effect on people seven generations into the future.

In Canada, governments have a legal duty to consult Indigenous communities when a project, like a road, a pipeline or a dam, might affect their rights. Many projects today are planned in partnership with Indigenous communities, and some are owned or co-owned by them. Including Indigenous knowledge can lead to designs that better protect the environment and better serve communities.

Weighing the factors: a decision matrix

Usually no option is best in every way. There are trade-offs: a cheaper design may use more energy; a bigger design may harm more habitat. Engineers and planners often use a decision matrix: list the options, choose criteria, give each option a score for each criterion, and add up the scores. The community decides which criteria matter most.

Worked example

Let's evaluate three rink designs

Score each option from 1 (poor) to 3 (good) for four criteria. Option A: open-air rink with natural ice in the park. Option B: covered rink with a roof and a refrigeration system, next to the school. Option C: a full indoor arena with seating, at the edge of town.

Cost to build: A is cheapest (3), B costs more (2), C costs the most (1).
Environment: A uses no refrigeration energy (3). B uses some energy and is built on land that is already cleared beside the school (2). C uses the most energy and would clear a field at the edge of town (1).
Social: use and access: A works only in cold weather (1). B can be used in a longer season and students can walk to it (3). C is used all year but is hard to reach without a car (2).
Maintenance cost: A needs flooding and snow clearing but little else (3). B needs repairs to the roof and refrigeration (2). C has the highest heating, cooling and repair costs (1).
Totals: A = 3 + 3 + 1 + 3 = 10. B = 2 + 2 + 3 + 2 = 9. C = 1 + 1 + 2 + 1 = 5.

Option A scores highest (10), with B close behind (9). If the community decides use and access matters most (for example, counting it double), B scores 9 + 3 = 12 and A scores 10 + 1 = 11, so B wins. The choice depends on which factors the community values most.

The rink decision matrix as a stacked bar graph. Each block is one criterion's score (1 to 3). Option A totals 10, B totals 9 and C totals 5.

Worked example

Let's spot the factors

A city plans a new footbridge over a river. Sort these concerns: (a) the bridge must have ramps, not just stairs; (b) fish spawn under the planned site in spring; (c) the steel bridge is cheaper to build but must be painted every 15 years; (d) local welders and ironworkers will be hired.

(a) Ramps help people who use wheelchairs, walkers or strollers: social (accessibility).
(b) Fish habitat: environmental. The design might change the site or the construction schedule to avoid spawning season.
(c) Building cost and long-term maintenance cost: economic.
(d) Local jobs: economic (and also social, because it helps families in the community).

(a) social, (b) environmental, (c) economic, (d) economic (and social).

Just for fun

A decision matrix works for big choices, like where to build a rink. It also works for small ones. Try it on pizza toppings: cost, taste and how many friends will actually eat it!

Hands-on activity

Plan a structure for your community

You need: paper, a pencil, and a family member or friend to interview.

Choose a structure your community could use: a bus shelter, a skate park, a playground, a footbridge, a community garden shed, or an accessible ramp at a local building.
Interview two people (for example, a family member and a neighbour). Ask: Who would use it? What do you need it to do? What worries you about it?
List at least two environmental, two social and two economic factors.
Sketch two design options. Make a decision matrix with at least four criteria and score each option from 1 to 3.
Choose the best option and explain your trade-offs: what did you give up, and why?
Present your plan in a poster or a one-minute talk.

What to look for: factors in all three categories; at least one factor about accessibility; scores that are explained; and a clear statement of the trade-off (e.g., "Option 2 costs more, but it has a roof and a ramp, so more people can use it all year").

Your turn

What are the three kinds of factors to consider when designing a structure?

Is "the cost of heating a building for 50 years" an environmental, social or economic factor?

Give an example of a social factor.

Give an example of an environmental factor.

What is a stakeholder?

Why should Indigenous communities be consulted about projects that affect their lands?

More practice: warm-up

A ramp at a library entrance is mainly which kind of factor?

Jobs created by building a new arena are which kind of factor?

Cutting down a forest to build a parking lot is which kind of factor?

What is a trade-off?

What tool can you use to compare design options with scores?

More practice: on your own

Why might a building in a remote fly-in community be designed differently from one in Toronto?

A cheap building design has poor insulation. Explain a trade-off.

How can a green roof (a roof covered with plants) help the environment?

Why are public meetings important before building a big structure?

Explain the idea of thinking seven generations ahead, and how it applies to building a dam.

Challenge

In the rink example, the community decides that environment matters most and counts it triple. Recalculate the totals. Which option wins?

A company wants to build a road through a wetland to reach a new mine. List one environmental, one social and one economic factor, and suggest one design change that could reduce harm.

Explain why the "best" design for a structure can be different for two communities, even if the structure has the same purpose.

Check your understanding

Quiz

Which is a social factor?

Which is an economic factor?

Which is an environmental factor?

A stakeholder is...

In Canada, when a project might affect Indigenous rights, governments have a duty to...

In a decision matrix, Option X scores 3, 2 and 2 on three criteria, and Option Y scores 1, 3 and 3. Both total 7. What is the best next step?

For parents and teachers

Big idea (D1.1, D1): Students evaluate environmental, social and economic factors in designing and building structures to meet the needs of individuals and communities, including urban, rural and remote communities. They learn about the duty to consult and the value of Indigenous knowledge (A3.3), and about jobs in construction (A3.1).

How to help: Talk about a real project near you (a new school, road, arena or bridge). Ask: "Who benefits? Who might be harmed? What does it cost now and later?" Help your child interview two people for the activity.

Common difficulties:

Only thinking about cost. Ask for at least two factors of each kind.
Thinking there is one right answer. Decisions involve trade-offs and depend on community values; a good answer explains its reasons.
Speaking about Indigenous peoples only in the past. Emphasize living communities with rights and knowledge today.