What does it take to make a multiplex? A lot of planning and a healthy budget

Architect Tom Knezicknows multiplexes.

The Solares Architecture co-founder hasdesigned at least a dozen of themand even built somehimself.

With Toronto set to permit theirwideradoptionacross city neighbourhoods, he's anticipating they'll becomeeasier to build, withfewer developmenthurdles to deal with.

"It's exciting. It makes a big difference," said Knezic, whose recentwork includes a soon-to-be-completed fourplexin Toronto's Regal Heights neighbourhood.

"It overcomes many of the problems that we've had in this type of development."

Last month, Toronto city councillors voted in favour of approving the building of duplexes, triplexes and fourplexes in neighbourhoods across the city, though the associated amendments are not yet in effect.

A more plentiful supply of multiplexescould deliver more housing choicesfor some Torontonians, though any bump inaffordable housing stock is seeminglyunlikely.

Yetbuilding design and development expertssay the multiplex form can givemore people a home on the same parcels ofland, while providing options for revampingproperties accordingly.

"The city has to do a lot of things to resolve the housing issues that we're experiencing right now," said GraigUens, director of planning at Toronto's Batory Management, pointing to establishing a new generation of multiplexes as one such step.

"What it will do is introduce greater variety of rental housing into areas of the city where there's great demand for it," added Uens, who previously worked as a senior planner for the city.

Here's a brieflook at what's involved in the making of a multiplex.

Assessing what's possible

How does it start?

Michael Piper, an assistant professor of urban design and architecture at the University of Toronto, said the first step is to figure out what's permissible and then what's possible on a particular lot.

"Often times, people contact a builder or an architect to facilitate that," said Piper.

With Torontoniansnow allowed to build multiplexes, those questions shift to how to build these dwellings, as opposed to whetherthey can be built.

When it gets to the design side of things, Piper said outside expertisecould involve a builder, designeror architect, but always someone licensed "tosubmit code-approved drawings."

Melanie Melnyk, a project manager with Toronto's city planning division, said projects of this nature involve a level of complexity, even with the city taking steps to make their general undertaking more accessible for residents.

"These are homes and we want them to be safe and well constructed," she said in an interview.

Planning remains a must

Even with a more supportive climate for development, there's still a lot of planning involving with the making of a multiplex.

WATCH |A look inside a multiplex project:

Making a multiplex in Toronto

1 year ago

Duration 2:08

Toronto-based architect Tom Knezic explains the work that has gone into the making of a soon-to-be complete fourplex in the city's Regal Heights neighbourhood.

For Knezic's work on the Regal Heights property, the construction has moved ahead quickly, but lots of prep work preceded that. And there's more to do, as approval is still being sought to add a laneway suite at the rear of the property.

Design work started 18 months ago, Knezic said during a recent tour of the fourplex,which was previouslya three-unit building.

Knezic expects these types of projects to beless complex and less costly to pursue in future and so do city planners.

Philip Parker, a project manger inToronto'scity planning division, said thepending changes mean that someone who wants to build a multiplex no longer has to seek a rezoning or minor variance process to do that.

"The big change, I think, is the certainty that this building is actually allowed in the whole city," said Parker markinga "huge difference" for more than two thirds of city neighbourhoods.

Also, changes approved by council last yearmean that many people building multiplexes will no longer have to pay costly development charges.

Parker noted that such charges could have amounted to "hundreds of thousands of dollars" in the past.

Not a budget renovation

Reducing costs may bekey for driving development, as turning a home into a multiplex is not an inexpensive endeavour.

Builder Sebastian Clovis,the host and executive producer of HGTV Canada's Gut Job, says it would not be surprising to spend $500,000 converting a single-family home into a multi-unit residence.

Why? There's a lot of work involved including allthe needed plumbing, electrical andstructural upgrades.

Such projects may involve moving windows, adding separate entrances and other significant adjustments like dealing with a basement that needs to be lowered, a common issue in Toronto that Clovis said could cost $80,000 just todo the digging.

"These renovations really are all-encompassing," said Clovis, echoing comments from fellow professionals on thescope of potential work.

Despite the challenges that come with building, the University of Toronto's Piperdoesn't want people to feel dissuaded.

"Ithink the more it gets done, the easier it'll get," he said.

Inspiration from the past?

Those who look carefully at the homes dotting Toronto neighbourhoods will find examples of this kind of housing already in place.

This includes duplexes and even walk-up apartments built decades ago.

"There's a whole vocabulary of building language, which is beyond the little single-family dwelling, to the tall condo built form that we've all become so accustomed to," said Philip Evans, a principal at ERA Architects, an architecture and planning firm that has studied some of these long-present forms of housing in Toronto.

Beyond historical precedent or possibleinspiration, there may be practicallessons to be drawn from the ways that similar types of older housing can be adapted.

A research project that Piper is part of has been building a catalogue of types of old houses commonly found across the city, and researching how they can be converted into denser forms of housing.

At the city level, there are plans to develop FAQ-type material on multiplex building for the public thoughthat's still in the works.