Building Code for Deck Railings

Question Icon
Posted by: from Waterdown
4/10/2019 at 1:33:29 PM

I have an existing deck(20yrs) that is off the main floor where I also have a walk out from the basement. So the deck is 6-7 feet off the ground. The framing is still solid with no rot.

I'm looking to replace the deck boards. I'd also like to change to 4x4 railing posts. The old railings were never real sturdy and don't like the style.

Looking for what is code for the city of Hamilton (Ontario).

-What is the required height for the railings?

-Proper way to mount the 4x4 posts.


Top Deck Contractors in Hamilton

User Icon
Date/Time4/10/2019 at 2:11:18 PM

Once the difference in elevation to adjacent grade exceeds 1800 mm (6') you require a height of 1070 mm (42"); less than 6' and it's 900 mm (36").

Guards in this application (exterior guards serving not more than 2 dwelling units) are required to resist a horizontal load applied inward or outward at any point at the minimum required height of the guard of 0.5 kNm or concentrated load of 1.0 kN applied at any point. Also must resist a horizontal load applied inward or outward on elements within the guard, including solid panels and pickets of 0.5 kN applied over a maximum width of 300 mm and a height of 300 mm.

Hope this is clear as mud :)

This is a fairly recent introduction to the Code and probably your old railings didn't need to meet any kind of strength requirement. Best thing is to have the posts securely sandwiched in place with the joists, beams, blocking, bolts, etc. There's no specific methodology described in the Code.

User Icon
Date/Time4/11/2019 at 11:27:06 PM

Hi Mark,

Minimum code could range between 36"-42". There are other factors to consider though to.

For example, if min code calls for 36", but you have toddlers, why not go 42"....keep safety for all in when building...over & above for code & safety.

Always bolt and glue posts to the beam if possible, or joists.

Your local authority may be able to assist you. Seems you need a permit, ask a lot of questions when submitting your drawings.

User Icon
Sergey from Maple Exteriors Inc in Vaughan
Date/Time4/17/2019 at 8:14:34 PM

Hi, height of your railing must be 42 inch with ontario building code. from anything 2feet over grounds needs railings. 36 inch up to 6 ft and 42 inch higher than 6ft. Best way to mount post is attach to frame before you put boards.

User Icon
Date/Time5/10/2019 at 4:01:43 PM

I just learned from another 'Ask the Pros' post that in Ontario there is a supplementary standard OBC SB-7 which describes accepted methodologies for building interior and exterior railings which is view-able online. (The Alberta Building Code does not have such a standard.)

Search the TrustedPros directory and discover the best contractors in your area.

Find your home service pro
Great renovations start with a great contractor.

Since 2004, TrustedPros has been helping homeowners find the right contractor for their home improvements and repairs.

Post Your Project

Within hours you'll be comparing offers from top-rated professionals. It's free to post and you're under no obligation to hire.

Trustedpros Inc. does not warrant the accuracy, completeness, safety, legality or usefulness of any Content, or Whether Content is Current and up-to-date, and TrustedPros Inc. Shall have no liability whatsoever with respect to your use or reliance upon any content or for content being removed or otherwise ceasing to be available. Please refer to the terms and conditions of use of this websites for more details.

Get quotes from top-rated contractors