Muskoka Modern Prefab

Lake Muskoka, Ontario

This residence was water access only, and was installed from the lake side. There was an existing cottage already on the site, and after consulting with the municipality and using some site sensitivity analysis, we decided to grandfather the location of the existing building. So, after removing the old cottage, we replaced it with this new bunkie on the same site. Given these two conditions—water access only, and not wanting to overly disturb the site—prefab was the obvious building technique. Given our prefab capacity, this seemed like a great opportunity to move forward with a unit that we shipped in by boat and placed on the existing footprint.

Sleeping cabins on cottage properties in Ontario are generally (depending on the municipality) required to be around 600 sq. ft. or less. In this case, we achieved a very efficient space layout of two bedrooms with full bathroom and living space in only 480 sq. ft enclosed. It looks like a corner unit condo from a downtown high-rise out in nature.

On our modular platform in the shop, we can do anything in 400 to 600 sq. ft in single module, which is just around this size. The applications for this kind of construction are endless, whether we build and drop in a boathouse, Muskoka Room, screen porch, small sleeping cabin, or any accessory structure such as a workshop storage room, hybrid carport, or remote office. The prefab unit is a very efficient way to build, and allows us to create a complex architectural product very quickly and position it with less damage and disturbance to the existing site than a traditional onsite build.


The quick build time and low level of impact has made many of our clients chose the prefab style of building over the traditional type. The best part is we can still achieve a very high-quality product in a faster time frame, meaning our clients can get into their cottage faster.

In a traditional build onsite situation, with such a small footprint, only two or three construction personnel can work at once. Trades have to arrive onsite, set up equipment and do their work, then take down their equipment—and it’s the same for each building, large or small. A prefabricated unit, built offsite, allows us to achieve the economy of scale for a small sleeping cabin that is not possible onsite. Often these small buildings become expensive as they are dealt with in the same way a cottage would be. All materials and personnel have to move on and offsite in a regular situation. In our shop, we can have more people working at once, and without each trade having to travel to and from a remote location. We’ve noticed prefab has a huge advantage in these situations, which is why we’ve been especially building these small size units in our shop.

By comparison, we can install the kitchen in our shop while putting the roof on a prefab. All materials remain dry and clean, are locked up at night, with no rain delays, bugs, or having to take out and put away tools.

This particular project is a great example of one of our well-developed prefab units. Often people think of a trailer when they think of a prefab bunkie or cottage. But as architects, we can accomplish an extremely high level of design and finish in a modular form without it resembling a trailer. There is a difference only in the construction technique and how and where it is built. There’s no compromise on quality and sophistication between custom-site build and custom-modular.

This prefab is exciting because we configured the two sides of the building into structural curtain walls. This means the windows are actually holding up the roof, which makes the design concept into a beautiful glass box without the large steel structure that normally accompanies this kind of idea. The roof is cantilevered and hangs out to protect the deck on two sides, and has amazing solar geometry with floor-to-ceiling glass. This doesn’t feel or look like a basic module or a plain box, which is often a challenge with prefab. There is a unity to the design, which is what we always strive for at Altius, coupled with that special element of uniqueness we instill into each project.

In terms of sustainability, prefab tends to reduce waste and allow us to easily accomplish a high-quality building enclosure.

For the interior finish, we used modern white oak flooring which continues up wall and across ceiling for a natural, traditional cottage feel with a very modern look. We contrasted the white oak with white Corian, so everything from the bathroom to the integrated white desk is made out of Corian. We did this to keep the material palette simple, clean and modern. The sliding glass partitions give privacy to bedrooms at night and when used as reading nooks during the day.