The owners of this house would like to expand. How can this be done efficiently, while improving the overall look of the façade?

Several constraints must be considered in this case: The septic tank is to the right of the house; the addition should add as much space as possible and be bright; and it should be harmoniously integrated to the rest of the house.
The owners of this house would like to expand. How can this be done efficiently, while improving the overall look of the façade?

Several constraints must be considered in this case: The septic tank is to the right of the house; the addition should add as much space as possible and be bright; and it should be harmoniously integrated to the rest of the house.

© Société d'histoire du Lac St-Jean, 2004. All Rights Reserved.

Colour photo of the house before the project

Adding onto a traditional half-hip roof house.

Société d'Histoire du Lac-Saint-Jean

© Société d'histoire du Lac St-Jean, 2004. All Rights Reserved.


1 - The addition must be harmoniously positioned

Adding on to a house can considerably change its proportions. It is therefore recommended to add on to the rear of the house. Any frontal construction would require alterations to the façade, either to the right or to the left of the front door.

By placing the addition to the rear of the house, frontal harmony is preserved. It is even possible to renew with the original style by enlarging the doors and windows, as well as the porch, while respecting the original symmetry.

If it is impossible to add on to the rear of the house, the following are a few basic principles that can lead to successful results on one or the other side of the house.
The roof of the addition must be separate from the existing roof. The roof of the addition must have the same slope as the existing roof. The new construction must be set back from the main structure by at least 45 cm (18 inches). Otherwise, the façade is out of proportion:

By setting back the addition, the o Read More
1 - The addition must be harmoniously positioned

Adding on to a house can considerably change its proportions. It is therefore recommended to add on to the rear of the house. Any frontal construction would require alterations to the façade, either to the right or to the left of the front door.

By placing the addition to the rear of the house, frontal harmony is preserved. It is even possible to renew with the original style by enlarging the doors and windows, as well as the porch, while respecting the original symmetry.

If it is impossible to add on to the rear of the house, the following are a few basic principles that can lead to successful results on one or the other side of the house.
  1. The roof of the addition must be separate from the existing roof.
  2. The roof of the addition must have the same slope as the existing roof.
  3. The new construction must be set back from the main structure by at least 45 cm (18 inches).
Otherwise, the façade is out of proportion:

By setting back the addition, the original façade of the house can be preserved.

2- The dimensions of the addition must be proportioned to those of the house

If possible, avoid building an addition that is too large, too wide or too high, either to the side or the rear of the house. The added façade should not exceed one-third to one-half the width of the original façade.

A construction that is too high results in an unbalanced roof line:
If it is too wide, the overall look is disproportionate.

3- The architectural elements of the house should be reproduced on the addition

The addition should be in harmony with the original architectural style of the house, using the same materials:
  1. Half-hip of the roof
  2. Roofing material
  3. Roof incline
  4. Window types
  5. Ornamentation
  6. Exterior siding
The renovations yielded some noteworthy improvements: Added space, the addition of a window for more sunlight, and a better integration of the porch.

© Société d'histoire du Lac St-Jean, 2004. All Rights Reserved.

Sketch of examples of incorrect alterations to the façade

Examples of alterations to the façade

Société d'Histoire du Lac-Saint-Jean

© Société d'histoire du Lac St-Jean, 2004. All Rights Reserved.


Sketch of lateral addition

  1. The roof of the addition must be separate from the existing roof.
  2. The roof of the addition must have the same slope as the existing roof.
  3. The new construction must be set back from the main structure by at least 45 cm (18 inches).

Société d'Histoire du Lac-Saint-Jean

© Société d'histoire du Lac St-Jean, 2004. All Rights Reserved.


Sketch of a set-back addition

Set-back addition

Société d'Histoire du Lac-Saint-Jean

© Société d'histoire du Lac St-Jean, 2004. All Rights Reserved.


Sketch of a proportional addition

Proportional Addition

Société d'Histoire du Lac-Saint-Jean

© Société d'histoire du Lac St-Jean, 2004. All Rights Reserved.


Sketch of a house with architectural elements indicated

  1. Half-hip of the roof
  2. Roofing material
  3. Roof incline
  4. Window types
  5. Ornamentation
  6. Exterior siding

Société d'Histoire du Lac-Saint-Jean

© Société d'histoire du Lac St-Jean, 2004. All Rights Reserved.


Colour drawing of the results of the addition

Result of the addition

Société d'Histoire du Lac-Saint-Jean

© Société d'histoire du Lac St-Jean, 2004. All Rights Reserved.


Learning Objectives

The learner will:
  • describe the evolution of homes in Canada and the architectural influences that have marked them;
  • compare house styles and materials used in the past with those used today, then identify similarities and differences between them;
  • assess the impact of some materials on the environment and the manufacturing (and architectural style) of houses;
  • explain the influence of history (for example: the Conquest, the Confederation) on the architectural style and its evolution.

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