Since 2010, Demex Decks has been at the forefront of deck construction in Markham. With over a decade of experience, we have honed our skills and perfected our craft, ensuring that every deck we build is of the highest quality. Our team of skilled professionals is well-versed in the latest industry trends and techniques, guaranteeing a deck that not only meets but exceeds your expectations.

With our extensive experience, commitment to customer satisfaction, and dedication to delivering the best value, we are the top choice for all your deck building needs.


Years Experiences
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We are trusted for our work and provide it with a warranty.

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Free Quota

In addition to a free quote, we'll help you keep within your budget.

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Professional Tools

Ready to work, we use professional equipment.


Building Your Dream Project


Customer satisfaction is at the heart of everything we do at Demex Decks. We take immense pride in our work and are dedicated to ensuring that every customer is delighted with their new deck. From our first interaction to the final walk-through, we prioritize clear communication, prompt service, and attention to detail. Our commitment to excellence has earned us a reputation as the most trusted deck builder in Markham, with countless satisfied customers who continue to recommend our services.
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When it comes to deck construction, we believe that customization is key. Every homeowner has unique preferences and requirements for their outdoor space, and we are here to bring your vision to life. Our team of talented designers will work closely with you to create a deck that perfectly complements your home’s architecture and reflects your personal style. From deck size and layout to material selection and finishing touches, we pay meticulous attention to detail to ensure that every aspect of your deck is tailored to your preferences.
Rooftop Deck
Second-Floor Or Walk-Out
Pool Deck
Multi-Level Or Multi-Tier
Backyard Deck
Attached Deck
Detached or Free-Standing
Floating Deck


Ready to turn your outdoor dreams into reality? Contact Demex Decks today to schedule a consultation and take the first step towards your dream deck. Our team of experts is eager to discuss your project, answer your questions, and provide you with a no-obligation quote. Discover why we are the preferred deck builder in Markham and let us create a beautiful, functional, and lasting addition to your home.


At Demex Decks, we not only strive to deliver exceptional craftsmanship but also offer the best value for your investment. We understand that budget is an important consideration for homeowners, which is why we work closely with you to find cost-effective solutions without compromising on quality. With our extensive network of suppliers and industry connections, we source the highest-quality materials at competitive prices, passing the savings on to you. When you choose Demex Decks, you can trust that you are getting the best value for your money.


What neighborhoods in Markham do we serve?

As the leading deck builder in Markham, we proudly serve all neighborhoods in the area. Whether you reside in Unionville, Milliken, Cornell, or any other community in Markham, we are here to transform your outdoor space into a stunning, functional, and inviting deck. Our extensive service area ensures that homeowners throughout Markham have access to our exceptional deck building services.

How long it takes to build a deck?

The size of the deck should be taken into consideration, the more complex the deck design, the longer it may take to complete. On average, deck construction in Markham takes between 5 to 14 business days. The exact timeline for deck construction can be given after the project design has been surveyed and agreed upon.

How much it costs to build a deck?

You can calculate the approximate cost of a deck using the data on the cost page. To calculate the full cost, you need to be an expert in deck building and understand all the technical aspects, know the quantities of all materials needed and their costs, as well as your city’s deck building codes. Or simply contact us for an estimate.

How to contact the Building Services ​Department in Markham?

Address: 101 Town Centre Boulevard, Markham, Ontario, L3R 9W3

Phone: 905-475-4858

Email: buildingstandards@markham.ca

Is a permit required to build a deck in Markham?

Before starting any construction, demolition or renovation project, you must obtain a building permit. Here we’ve listed the exceptions.


Please keep in mind that the answers below are intended for general use only and may not apply to every situation. Please contact a Building Standards Department in Markham for advice on whether your project requires a permit.


Whether the work is on the interior or exterior of the building or dwelling, you will need a building permit. If you’re only doing work inside a dwelling, you can’t get an exemption.


You don’t need a Building Permit for the following housing projects:

  • Constructing detached single-storey accessory buildings (no plumbing) less than 15 m2 in area
  • Decks less than 600 mm (24 inches) above existing grade at all locations
  • Interior damp-proofing basements
  • Replacing plumbing fixtures or water heaters
  • Replacing a furnace or adding air conditioning units or a heat pump
  • Electrical projects
  • Kitchen or bathroom cupboards
  • Painting and decorating
  • Maintenance and repairs
  • Replacing windows or doors with no changes to the size of the rough opening
  • Replacing roofing or shingles
  • Fences other than a pool enclosure fence
  • Retaining walls less than 1 meter in height
  • Sidewalks, planters and landscaping
  • Ground or roof mounted solar photovoltaic panels

Which are Zoning By-law Standards in Markham?

The city is currently governed by 42 separate land-use ordinances which apply to different areas of the city. The Town’s zoning ordinances were adopted in the 1950’s and the majority of them were adopted prior to 1980. Many city ordinances, particularly pre-1995, are not in digital format and are not available online. Frequently requested sections of these ordinances, such as the current Decks Ordinance and the Home Occupation Ordinance, have been made available in digital format.


For the Decks By-law (By-law 142-95) for urban development areas, see Decks Regulations.


By-Law 177-96, the office consolidated version of which is available here Urban Area Decks Regulation (By-Law 177-96), governs most of the city built after 1995, including areas such as Cornell, Bertschi, Wismer, Angus Glen, Box Grove, and Cathedral City.


In addition to other regulations, By-Law 177-96 contains separate rules for residential decks and for occupancies.


You can use a property information search to find your address if you don’t know which ordinance applies to your property.


If you are not sure which zoning regulations apply to your property, you can do an online search. City staff will provide you with excerpts from the relevant zoning ordinance. You may conduct a preliminary review if you are unsure whether your project complies with the applicable zoning ordinance.


Land Use Bylaws can be inspected or purchased at City Planning, Markham Civic Centre at Thornhill Entrance, 101 Town Centre Boulevard, Markham, Ontario, L3R 9W3 or by e-mail at dsc@markham.ca.

What building codes govern the construction of decking in Markham?

It is imperative that your project complies with the Ontario Building Code, the Town of Markham Zoning By-law and other required approvals. You can read the Ontario Building Code of May 12, 2023 below.



Are there any guides for building a residential deck for homeowners in Markham?

We suggest reading the public guide.